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KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL CAPITAL WORKS DREDGING ENVIRONMENTAL ASSESSMENT Appendices D and E
Prepared for Ports of Auckland Limited
November 2019
iii KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT
Limitations This report has been prepared by Kennedy Environmental Limited (KEL) under contract for its client. The report has been prepared to a specific scope of work. The report cannot be relied upon by a third party for any use without written consent of KEL and or its client.
This report may not be reproduced or copies in any form without the permission of the client. Such permission is to be given only in accordance with the terms of the client’s contract with KEL.
Document Revision History Revision Author Version Date of release
1 P Kennedy Issue to N Ironside POAL for Review 23 August 2019
2 P Kennedy Issue to N Ironside POAL for Review 30 September 2019
3 P Kennedy Issue to N Ironside POAL 14 October 2019
4 P Kennedy Issue to A Blomfield Bentley 25 October 2019 5 P Kennedy Issue to A Blomfield Bentley 18 November 2019
Bibliographic Reference This report should be referenced as:
KEL 2019. Rangitoto Channel Capital Works Dredging Environmental Assessment. Prepared for Ports of Auckland Limited by Kennedy Environmental Limited, November 2019.
iv KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT
Table of Contents Limitations ................................................................................................................................................... iii Document Revision History .......................................................................................................................... iii Bibliographic Reference ............................................................................................................................... iii List of Figures .............................................................................................................................................. vii List of Tables .............................................................................................................................................. viii List of Abbreviations & Units ........................................................................................................................ x 1 INTRODUCTION .......................................................................................................................................... 1
1.1 Rangitoto Channel Dredging ......................................................................................................... 1 1.2 Unitary Plan Assessment Requirements ..................................................................................... 1 1.3 Report Contents ............................................................................................................................... 3
2 PROPOSED DREDGING ............................................................................................................................... 4 2.1 Introduction ....................................................................................................................................... 4 2.2 Dredging Location ........................................................................................................................... 5 2.3 Timing of Dredging. ......................................................................................................................... 5 2.4 Capital Dredging Areas and Volumes .......................................................................................... 7 2.5 Dredging Depths .............................................................................................................................. 7 2.6 Method of Dredging ......................................................................................................................... 8
3 PHYSICAL ENVIRONMENT .......................................................................................................................... 8 3.1 Introduction ....................................................................................................................................... 8 3.2 Tides and Currents .......................................................................................................................... 9 3.3 Geological Environment ............................................................................................................... 10 3.4 Channel Sediments ....................................................................................................................... 10 3.5 Sediment Physical Characteristics.............................................................................................. 11 3.6 Waitemata Group Material ........................................................................................................... 16
4 SEDIMENT QUALITY ................................................................................................................................. 17 4.1 Introduction ..................................................................................................................................... 17 4.2 Sources of Contaminants ............................................................................................................. 17 4.3 Organic Carbon .............................................................................................................................. 18 4.4 Trace Elements .............................................................................................................................. 18 4.5 Hydrocarbons ................................................................................................................................. 21 4.6 Organochlorine Compounds ........................................................................................................ 23 4.7 Antifoulants ..................................................................................................................................... 24 4.8 Summary ......................................................................................................................................... 24
5 WATER QUALITY ....................................................................................................................................... 24 5.1 Introduction ..................................................................................................................................... 24 5.2 Water Quality Information ............................................................................................................. 25 5.3 Turbidity and Total Suspended Solids........................................................................................ 25 5.4 Nutrients .......................................................................................................................................... 29 5.5 Summary ......................................................................................................................................... 30
6 INTERTIDAL & BENTHIC ECOLOGY OF THE NAVIGATION PRECINCT ........................................................ 30
v KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT
6.1 Introduction ..................................................................................................................................... 30 6.2 Supporting Studies for this Application ...................................................................................... 31 6.3 Intertidal Ecology ........................................................................................................................... 31 6.4 Sub-tidal Habitats .......................................................................................................................... 32 6.5 Epifauna .......................................................................................................................................... 34 6.6 Infauna ............................................................................................................................................ 39 6.7 Overview ......................................................................................................................................... 44 6.8 Biosecurity ...................................................................................................................................... 44 6.9 Sensitive Habitats and Conservation Significance ................................................................... 49
7 OTHER FAUNA .......................................................................................................................................... 50 7.1 Seabirds .......................................................................................................................................... 50 7.2 Fish .................................................................................................................................................. 52 7.3 Marine Mammals ........................................................................................................................... 56 7.4 Terrestrial Biosecurity ................................................................................................................... 58 7.5 Summary ......................................................................................................................................... 59
8 ENVIRONMENTAL EFFECTS OF PROPOSED DREDGING............................................................................ 59 8.1 Introduction ..................................................................................................................................... 59 8.2 Physical Effects .............................................................................................................................. 60 8.3 Water Quality Effects – Suspended Sediment .......................................................................... 60 8.4 Water Quality Effects – Contaminants ....................................................................................... 64 8.5 Effects of Sedimentation ............................................................................................................... 69 8.6 Ecological Effects - Seabirds ....................................................................................................... 72 8.7 Ecological Effects - Marine Mammals ........................................................................................ 74 8.8 Ecological Effects - Fish ............................................................................................................... 76 8.9 Ecological Effects - Biosecurity Risks ........................................................................................ 79 8.10 Ecological Effects - Habitat Changes ....................................................................................... 81 8.11 Ecological Effects - Food Web/Ecosystem Effects ................................................................ 84 8.12 Effects on Ecological Values ..................................................................................................... 84
9 MITIGATION & MONITORING .................................................................................................................. 85 9.1 Monitoring ....................................................................................................................................... 85 9.2 Mitigation ......................................................................................................................................... 88
10 SUMMARY & CONCLUSIONS .................................................................................................................. 89 10.1 Ecological Environment .............................................................................................................. 89 10.2 Sediment and Sediment Quality ............................................................................................... 90 10.3 Water Quality ............................................................................................................................... 90 10.4 Effects of Suspended Sediment ................................................................................................ 90 10.5 Effects of Sedimentation ............................................................................................................ 91 10.6 Effects on Sediment Quality ...................................................................................................... 91 10.7 Effects of other Water Quality Changes .................................................................................. 91 10.8 Effects of Noise ............................................................................................................................ 91 10.9 Barge and Vessel Movement .................................................................................................... 92
vi KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT
10.10 Biosecurity .................................................................................................................................. 92 10.11 Recolonisation ........................................................................................................................... 92 10.12 Monitoring and Mitigation ......................................................................................................... 93
11 REFERENCES ........................................................................................................................................... 93 Appendix A : Dredging areas and depths and 2004-2007 dredging areas. .............................................. 104 Appendix B : FNB and Rangitoto Channel Sediment sampling and quality characterisation programme. .................................................................................................................................................................. 105 Appendix C : Visual assessment of marine habitats Rangitoto Channel & Fergusson Wharf (Ramboll 2019). ........................................................................................................................................................ 106 Appendix D : Rangitoto Channel benthic community composition (Marlow 2019). ................................ 107 Appendix E : Survey of non-indigenous biota in the WCNP (Woods et al. 2019a). .................................. 108 Appendix F : Example photographs from seabed locations visited during the Fugro survey (refer Appendix C) in 2019. ................................................................................................................................. 109 Appendix G : Example photographs from seabed locations visited during seabed surveys reported in Marlow (2019) and Woods et al. (2019a). ................................................................................................ 110
105 KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT
Appendix D: Rangitoto Channel benthic community composition (Marlow 2019).
REPORT NO. 3367
RANGITOTO CHANNEL BENTHIC COMMUNITY COMPOSITION REPORT
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
RANGITOTO CHANNEL BENTHIC COMMUNITY COMPOSITION
JOSEPH MARLOW
Prepared for Ports of Auckland Ltd
CAWTHRON INSTITUTE 98 Halifax Street East, Nelson 7010 | Private Bag 2, Nelson 7042 | New Zealand Ph. +64 3 548 2319 | Fax. +64 3 546 9464 www.cawthron.org.nz
REVIEWED BY: Olivia Johnston
APPROVED FOR RELEASE BY: Roger Young
ISSUE DATE: 16 July 2019
RECOMMENDED CITATION: Marlow J 2019. Rangitoto Channel benthic community composition. Prepared for Ports of Auckland Ltd. Cawthron Report No. 3367. 12 p. plus appendices.
© COPYRIGHT: This publication must not be reproduced or distributed, electronically or otherwise, in whole or in part without the written permission of the Copyright Holder, which is the party that commissioned the report.
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
v
TABLE OF CONTENTS
1. INTRODUCTION ........................................................................................................... 1
2. METHODS ..................................................................................................................... 1
2.1. Sample sites ................................................................................................................................................... 1
2.2. Macrofauna communities ............................................................................................................................... 1
2.3. Sediment analysis .......................................................................................................................................... 2
2.4. Multivariate analyses ...................................................................................................................................... 3
3. RESULTS AND DISCUSSION ....................................................................................... 4
3.1. Infaunal community composition .................................................................................................................... 5
3.2. Invasive species ........................................................................................................................................... 10
3.3. Comparison with previous studies ................................................................................................................ 10
4. REFERENCES .............................................................................................................11
5. APPENDICES ...............................................................................................................13
LIST OF FIGURES
Figure 1. Map of seven macrofaunal survey locations within the Rangitoto Channel, Hauraki Gulf, April 2019. .................................................................................................................. 2
Figure 2. Average total infaunal abundance, taxonomic richness, diversity and evenness at sample sites within the Rangitoto Channel. ........................................................................ 4
Figure 3. Principal component analysis (PCO) depiction of infaunal community similarities among samples. .................................................................................................................. 7
Figure 4. Distance based redundancy analysis (dbRDA) ordinations of fitted models for assemblage composition. ................................................................................................... 9
LIST OF TABLES
Table 1. The most common taxa (100 or more individuals) in infaunal samples from the Rangitoto Channel. ............................................................................................................. 5
Table 2. Five most common taxa at each survey site. ...................................................................... 8
LIST OF APPENDICES
Appendix 1. Example images of sediment types (within van Veen grabs) seven sites sampled in the Rangitoto Channel in 2019. ........................................................................................ 13
Appendix 2. Species list and abundance for each infauna sample. ...................................................... 15 Appendix 3. Results from SIMPER analysis of species composition similarity and dissimilarity
within and between sites, respectively.. ............................................................................ 21
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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1. INTRODUCTION
The Rangitoto Channel in the inner Hauraki Gulf provides access to the Port of
Auckland for large commercial vessels. The channel was last dredged in 2004–2007
in order to increase capacity for larger container vessels (up to 4100 containers). It is
now 200 m wide and allows one-way passage of vessels of up to 12.5 m draught.
Ports of Auckland Ltd (POAL) is currently in the process of applying for capital
dredging consent to deepen the Rangitoto Channel and a small area near Fergusson
Container Terminal. Cawthron institute was commissioned by POAL to update
ecological survey work (previously extensively done in 2001) and to characterise
benthic macrofauna communities within the Rangitoto Channel.
2. METHODS
2.1. Sample sites
Seven sites (Figure 1) along the length of the Rangitoto Channel were selected to
represent a variety of substrate types and epifaunal assemblages. Selection was
based on data from previous surveys and the sites selected (from south to north)
were:
• B1010: shell hash & no epifauna
• B1168: shell hash, soft sediment & sponge beds
• B1236: shell hash & soft sediment
• B1297: variable; shell hash, coarse sand, soft sediment & sponge beds
• B1338: shell hash, soft sediment & no epifauna
• B1405: shell hash, soft sediment & moderate epifauna cover
• B1543: soft sediment & minimal epifauna.
See Appendix 1 for images of sediment types.
2.2. Macrofauna communities
In April 2019 at each of the seven survey locations, five replicate substrate samples
were obtained using a van Veen grab sampler. Photographs were taken of the
sediment surface within the grab to provide qualitative characterisation of substrate
type. The sediment within the grab was sub-sampled to 100 mm depth using a
113 cm2 core to obtain infauna. Core samples were gently washed over a 0.5 mm
sieve and preserved in a 95% ethyl alcohol and 5% glyoxal solution. Samples were
transported to Cawthron where they were microscopically examined; taxa were
identified to the lowest practical taxonomic resolution and numbers of individuals
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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(abundance) were calculated for each sample. Previous work has established the
presence of significant sponge beds and other large epifauna at the survey sites;
however, large epifauna were not detected within the van Veen grabs. Therefore, any
epifauna (e.g. small solitary ascidians) were included in the infauna analysis.
Figure 1. Map of seven macrofaunal survey locations within the Rangitoto Channel, Hauraki Gulf,
April 2019.
2.3. Sediment analysis
In addition to the infaunal sub-sampling of each grab sample, a sediment subsample
was retained for grain size analysis at Hill Laboratories Ltd. Each sediment sub
sample was characterised by the proportion of sediment grain sizes:
• > 2 mm = Gravel
• < 2 mm to > 1 mm = Coarse Sand
• < 1 mm to > 500 μm = Medium Sand
• < 500 μm to > 250 μm = Medium/Fine Sand
• < 250 μm to > 125 μm = Fine Sand
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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• < 125 μm to > 63 μm = Very Fine Sand
• < 63 μm = Mud (Silt and Clay)
Size classes are from Udden-Wentworth scale.
2.4. Multivariate analyses
Multivariate analyses were performed using PRIMER v7 software (Clarke & Gorley
2015) in order to determine differences in benthic community composition among
sites. All data were square-root transformed to preserve information on relative
abundance while reducing the influence of overly-abundant species. Differences in
community composition among sites were assessed using a one-way permutational
multivariate analysis of variance (PERMANOVA) based on a resemblance matrix
constructed using Bray-Curtis similarity coefficients (Anderson 2014). If a significant
difference was detected among sites a further pair-wise PERMANOVA was conducted
to determine which sites were significantly different. These differences were
represented visually using principal coordinate analysis (PCO) with overlaying
Pearson’s correlation vectors (r ≤ 0.7). The extent to which sediment grain size
influenced species composition was analysed using a distance-based multiple linear
regression model (DISTLM; Anderson 2004). In order to find the most parsimonious
model, Akaike’s Information Criterion (AIC), a step-wise procedure, adjusted for small
sample sizes (AICc), was used (Burnham & Anderson 2004). The results from this
analysis were represented graphically with a distance-based redundancy ordination
(dbRDA), and 2D bubble plots to identify differences in substrate composition. Finally,
an analysis of similarity percentages (SIMPER) was used to determine which taxa
contributed the most similarity/dissimilarity (in terms of abundance) within/among
sites.
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3. RESULTS AND DISCUSSION
A total of 7073 individual specimens across 174 different taxa were observed within
the 35 sediment samples (Appendix 1). The majority of infauna (54.2%) were
polychaete worms, followed by amphipods (13.6%), ophiuroids (8.1%), oligochaetes
(4.4%) and bivalves (3.1%).
Infaunal composition was variable across samples, with numbers of taxa per sample
ranging from 10 to 58 (average of 35.1 ± 12.6 (SD)) and numbers of individuals per
sample ranging from 23 to 558 (average of 204.4 ± 123.2). Abundance and taxonomic
richness were highest at B1168 where the respective average number of taxa and
individuals per sample was 49.6 (± 8.1) and 349.8 (± 134.9). Conversely, B1543 was
the most depauperate survey location with an average of 18.2 (± 6.7) taxa and 49.8
(±18.7) individuals per sample (Figure 2).
In contrast, differences in species diversity and evenness among sites were less
pronounced. Shannon-Wiener diversity index (H’) ranged from 2.4 at B11543 to 3.0 at
B1168, indicating relatively high species diversity across all sites. There was a slight
trend for a decline in species diversity from south to north, but also a large amount of
variation among samples. Pielou’s evenness index ranged from 0.71 at B1405 to 0.86
at B1297, indicating a fairly uniform distribution of species at most sites (Figure 2).
Figure 2. Average total infaunal abundance, taxonomic richness, diversity and evenness at sample
sites within the Rangitoto Channel. Error bars represent standard deviation.
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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3.1. Infaunal community composition
The most common taxa (Table 1) were polydorid worms (Spionidae), many species of
which bore and inhabit calcareous shells and substrates (Sato-Okoshi et al. 2008).
Other notable polychaetes were two spionids, Prionospio spp., and the capitellid
worms Heteromastus filiformis and Barantolla lepte. Both spionid and capitellid worms
are often used as indicators of stress due to their capacity to opportunistically
recolonise and dominate disturbed sediments. Exceptionally high abundances of
capitellids are also often associated (e.g. Wong & O’Shea 2011) with organic
enrichment. However, the moderate densities and lack of dominance by these worms
in the current survey are not indicative of enrichment or stress. The majority of the
other common taxa were also surface deposit feeders or scavengers (e.g.
Amphiuridae and Ischyroceridae) that feed on organic matter on or within the
sediment.
Table 1. The most common taxa (100 or more individuals) in infaunal samples from the Rangitoto Channel. ‘N’ is the total number of organisms counted across all samples.
Group Taxa N
Polychaeta: Spionidae Polydorid 649
Polychaeta: Syllidae Exogoninae 618
Ophiuroidea Amphiuridae 581
Amphipoda Ischyroceridae 492
Polychaeta: Capitellidae Heteromastus filiformis 428
Polychaeta: Paraonidae Paraonidae 396
Polychaeta: Syllidae Syllidae 393
Polychaeta: Spionidae Prionospio sp. 361
Oligochaeta Oligochaeta 313
Polychaeta: Capitellidae Barantolla lepte 218
Polychaeta: Spionidae Prionospio multicristata 126
Hemichordata Hemichordata 119
Polychaeta: Cirratulidae Cirratulidae 117
Isopoda Anthuridae 103
Amphipoda Amphipoda (juv.) 101
Polychaeta: Serpulidae Hydroides elegans 100
Multivariate analysis found that there were significant differences in infaunal
community composition among sites (PERMANOVA, Pseudo-F(6,34) = 3.9682, p =
0.001). The subsequent pairwise test showed that the majority of survey sites were
significantly different (p < 0.05) from each other with respect to their community
composition. The only exception was the infaunal communities at B1405 and B1297
which were not significantly different from each other (p = 0.22), although this appears
to be due to large within-site variability at each of the respective sites (Figure 3).
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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The PCO (Figure 3), illustrates the differences in community composition both within
replicates and among sites. At the 30% similarity level, the species composition at
B1543 (the most northerly site) was distinctly different from the other six sites.
However, a lack of overlap at the 50% level demonstrates community variability within
this site. The other six sites showed a moderate degree of within site similarity, with all
samples clustering within the 30% grouping. Furthermore, infaunal communities
B1168 and B1010 (with the exception of one B1168 sample) shared at least 50%
similarity as did the majority of B1236 and B1338 samples. Pearson’s correlation
vectors (>0.7) indicated that these clusters were associated with relatively higher
abundances of certain infauna taxa:
• B1543: Theora lubrica (Bivalvia)
• B1236 & B1338: Prionospio spp. and polydorids (Polychaeta)
• B1168 & B1010: Leptochiton inquinatus (Polyplacophora), Ischyroceridae
(Amphipoda), Exogoninae and Hesionidae (Polychaeta).
Community composition differences and similarities were further highlighted by the
SIMPER analysis (full results Appendix 3). Samples from B1168 and B1010 showed
the least variation in species composition, with an average within-site similarity of 59.1
and 57.4%, respectively. Conversely, samples from B1297 and B1543 showed the
lowest levels of within-site similarity at 33.4 and 35.5%, respectively. The largest
differences between sites were attributed to B1543 which was 79.2-84.2% different
from all the other sites. This appears to be due to the relatively low abundances or
absence of many taxa that were common at many other sites (e.g. Amphiuridae,
Exogoninae, Oligochaeta, Polydorid, Prionospio spp. and Syllidae) and high
abundances of Theora lubrica which was less common at other sites (Table 2). All
other between sites comparisons showed a lesser degree of dissimilarity (50.1-
65.3%), with B1168 and B1010 being the most similar. These sites shared high
abundances of Amphiuridae and Exogoninae but differed in their relative abundance
of Heteromastus filiformis, Ischyroceridae, Oligochaeta and Cirratulidae.
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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Figure 3. Principal component analysis (PCO) depiction of infaunal community similarities among
samples. On the left, samples are plotted by site with dotted lines representing 30 (green) and 50 % (blue) similarity. Overlaid vectors represent individual taxa that have a Pearson’s correlation coefficient of greater than 0.7 with either of the PCO axes.
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Table 2. Five most common taxa at each survey site. N = average abundance across five replicates.
Site Taxon Group Taxon N
B1010 Ophiuroidea Amphiuridae 42
Polychaeta Exogoninae 37
Amphipoda Ischyroceridae 28
Oligochaeta Oligochaeta 22
Polychaeta Syllidae 17
B1168 Polychaeta Exogoninae 48
Amphipoda Ischyroceridae 36
Ophiuroidea Amphiuridae 31
Polychaeta Heteromastus filiformis 26
Polychaeta Paraonidae 24
B1236 Polychaeta Polydorid 23
Polychaeta Prionospio sp. 15
Ophiuroidea Amphiuridae 12
Polychaeta Paraonidae 11
Polychaeta Heteromastus filiformis 9
B1297 Polychaeta Polydorid 14
Ophiuroidea Amphiuridae 10
Polychaeta Heteromastus filiformis 7
Polychaeta Paraonidae 7
Polychaeta Prionospio sp. 6
B1338 Polychaeta Polydorid 40
Polychaeta Syllidae 28
Polychaeta Prionospio sp. 23
Amphipoda Ischyroceridae 22
Oligochaeta Oligochaeta 22
B1405 Polychaeta Polydorid 47
Polychaeta Heteromastus filiformis 32
Polychaeta Prionospio sp. 19
Polychaeta Paraonidae 18
Polychaeta Exogoninae 17
B1543 Bivalvia Theora lubrica 12
Amphipoda Phoxocephalidae 5
Polychaeta Polydorid 5
Bivalvia Montacuta sp. 2
Ostracoda Ostracoda 2
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The DISTLM analysis found that sediment grain size explained 21.5% of the variation
in infauna community composition. The best model selected by the analysis shows
that the relative proportion of fine sand (125–63 µm) explained 14.8% and gravel
(> 2 mm) explained 6.7%. Figure 4 demonstrates that higher abundances of T. lubrica
were particularly associated with a greater substrate proportion of fine sand while
Exogoninae and Hesionidae were associated with a greater proportion of gravel.
Figure 4. Distance based redundancy analysis (dbRDA) ordinations of fitted models for
assemblage composition. Overlapping 2D bubbles represent substrate proportion of fine sand (left) and gravel (right). Overlaid vectors represent individual taxa that have a Pearson’s correlation coefficient of greater than 0.7 with either of the PCO axes.
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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3.2. Invasive species
As might be expected for one of New Zealand’s busiest international shipping
channels, benthic composition wasn’t entirely indigenous. Single specimens of the
invasive Mediterranean fanworm (Sabella spallanzanii) and the invasive ascidian
Styela clava were found at site B1168. Both these taxa have recently established in
the region; S. clava was first detected in the Viaduct harbour in 2005 and S.
spallanzanii was first detected at the entrance of the same harbour in 2009
(McFadden et al. 2007; Read et al. 2011). In addition to S. spallanzanii and S. clava,
14 specimens of the polychaete Leonnates sp. (Nereididae family) were found across
four sites (B1543, B1338, B1405 & B1236). Prior to 2017 no species of this
tropical/subtropical genus had been found in New Zealand waters. Leonnates sp. was
first found in Henderson Creek, Waitemata Harbour in October 2017 during routine
benthos sampling by NIWA and has since been recorded in the Viaduct area, Okura,
Waiwera Mahurangi (NIWA comm.) and the western Coromandel (Cawthron data).
There is currently some uncertainty over the identity of this species; initial taxonomic
work on the specimen found in Henderson Creek identified the worm as L.
stephensoni (Read 2017) which is endemic to Australia. However, L. stephensoni is
taxonomically very similar to L. persicus which is known to be a globally invasive
species (Sato & Kubo 2009). Cawthron is currently undertaking a molecular analysis
to determine whether the Leonnates sp. from the Rangitoto Channel is L. stephensoni
or L. persicus.
More established New Zealand invasives were the barnacle Balanus trigonus, and the
bivalves Theora lubrica and Limaria orientalis. These species are found throughout
New Zealand waters and were encountered in a previous survey during 2001 (Kingett
Mitchell 2001).
3.3. Comparison with previous studies
A previous comprehensive study of the benthic composition of the Rangitoto Channel
and port approaches prior to dredging in 2004–2007 (Kingett Mitchell 2001) found (to
varying degrees) similar macrofaunal community composition. However, differences in
survey locations, grab size and the level of taxonomic identification between the
studies make confident quantitative comparisons problematic. Similarities between the
2001 and 2019 surveys include:
• Infauna primarily dominated by polychaetes
• Dominance of syllid worms at southern sites
• Relatively high abundance of capitellid worms (primarily Heteromastus filiformis
and Barantolla lepte) across the survey region
• High amphipod abundance, however;
o Ischyroceridae were the most abundant in the present survey
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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o Ischyroceridae were not identified in 2001 (they may have been
recorded as an unidentified amphipod)
• Amphiurid brittle stars abundant at most sites in both surveys;
o Similar trend of decreasing abundance from south to north in 2001 and
2019
• High abundances of T. lubrica in the north of the Rangitoto Channel.
Differences include:
• Considerably higher abundances of polydorid polychaetes in the present study
• Molluscs accounted for less than 5% of all infauna, considerably less than in 2001
when molluscs comprised 15-20% of all infauna;
o In 2001, there were particularly high abundances of the gastropods
Pisinna olivacea impressa and Maoricolpus roseus roseus and the
bivalve Nucula hartivigiana at mid-channel sites
o While these taxa were observed in this survey (P. impressa recorded
as gastropod: microsnail), they were considerably less abundant
• Oligochaetes accounted for 4.4% of all infauna in 2019 but were almost absent
from surveys in 2001
Although it is difficult to make robust temporal comparisons between the two surveys
due to methodological differences, similarities suggest that recolonisation has
occurred and that the benthic communities are recovering. Furthermore, recovery
appears to be slowest among mollusc taxa, with boring polydorid worms potentially
benefiting from increase in habitat availability post-dredging.
4. REFERENCES
Anderson MJ 2004. DISTLM v. 5: a FORTRAN computer program to calculate a
distance-based multivariate analysis for a linear model. Department of
Statistics, University of Auckland, New Zealand 10:2016.
Anderson MJ 2014. Permutational multivariate analysis of variance (PERMANOVA).
Wiley StatsRef: Statistics Reference Online 14:1-5.
Burnham KP and Anderson DR 2004. Multimodel inference: understanding AIC and
BIC in model selection. Sociological Methods and Research 33: 261–304.
Clarke KR, Gorley RN 2015 Getting started with PRIMER v7. PRIMER-E: Plymouth,
Plymouth Marine Laboratory.
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Keeley NB, Macleod CK, Forrest BM 2012. Combining best professional judgement
and quantile regression splines to improve characterisation of macrofaunal
responses to enrichment. Ecological Indicators 12: 154-166.
Kingett Mitchell 2001. Assessment of the effects of the Rangitoto shipping lane
deepening project on natural resources. Report prepared by Kingett Mitchell for
Ports of Auckland Limited.
McFadden A, Rawdon T, Gould B, Border P 2007. Response to a marine incursion
Styela clava. Surveillance-Wellington 34:4.
Read GB, Inglis G, Stratford P, Ahyong ST 2011. Arrival of the alien fanworm Sabella
spallanzanii (Gmelin, 1791) (Polychaeta: Sabellidae) in two New Zealand
harbours. Aquatic Invasions 6: 273-279.
Read GB 2017. Notes on the Australian polychaete Leonnates stephensoni Rullier,
1965, collected from Henderson Creek monitoring site in Waitemata Harbour,
New Zealand. Marine Exotic Species Note 99. National Institute of Water and
Atmospheric Research, New Zealand.
Sato-Okoshi W, Okoshi K, Shaw J 2008. Polydorid species (Polychaeta: Spionidae) in
south-western Australian waters with special reference to Polydora uncinata
and Boccardia knoxi. Journal of the Marine Biological Association of the United
Kingdom 88: 491-501.
Sato M, Kubo A 2009. New records of the nereidid polychaete Leonnates persicus
from Japan, Korea, and Thailand, with a redescription of the holotype.
Zoological Science 26: 798-804.
Wong KL, O'Shea S 2011. The effects of a mussel farm on benthic macrofaunal
communities in Hauraki Gulf, New Zealand. New Zealand Journal of Marine
and Freshwater Research 45: 187-212.
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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5. APPENDICES
Appendix 1. Example images of sediment types (within van Veen grabs) seven sites sampled in the Rangitoto Channel in 2019.
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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Appendix 2. Species list and abundance for each infauna sample.
Taxa
B1168-A
B1168-B
B1168-C
B1168-D
B1168-E
B1543-A
B1543-B
B1543-C
B1543-D
B1543-E
B1338-A
B1338-B
B1338-C
B1338-D
B1338-E
B1010-A
B1010-B
B1010-C
B1010-D
B1010-E
B1297-A
B1297-B
B1297-C
B1297-D
B1297-E
B1405-A
B1405-B
B1405-C
B1405-D
B1405-E
B1236-A
B1236-B
B1236-C
B1236-D
B1236-E
Amphipoda
Ampelisca sp. 1 1 2 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 1 0 0 1 1
Aoridae 2 0 1 3 2 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 9 0 0 0 0 0 2
Atylidae 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 1 0 0 0 0 0 2 0 1 1 12 1 0 0 2 0 0
Caprellidae 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 1 0 0 3 0 0 0
Corophiidae 0 0 0 0 0 0 0 0 0 2 1 5 0 0 8 1 17 0 4 1 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0
Gammaridae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ischyroceridae 40 5 3 20 112 1 5 0 0 0 101 8 2 0 1 9 29 23 53 27 12 1 0 0 13 1 1 2 14 7 0 0 2 0 0
Leucothoidae 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Liljeborgiidae 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 0 0 0 1 2
Lysianassidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0
Melitidae 1 0 6 7 5 0 6 0 0 1 1 2 2 1 2 5 1 0 1 12 0 0 0 0 0 0 3 4 2 0 0 0 3 0 0
Oedicerotidae 2 3 0 0 1 0 0 0 0 0 0 1 2 1 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 2 0 1 3 0 0
Pardaliscidae 0 0 0 0 0 0 0 0 0 0 2 0 1 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 1 1 0 0 1 0 0
Phoxocephalidae 3 0 1 1 2 0 10 3 3 9 0 6 2 3 5 1 2 3 6 1 1 0 1 7 0 3 2 0 0 1 0 2 6 1 1
Amphipoda 0 0 11 0 0 0 0 0 0 1 2 0 0 2 13 0 9 10 0 0 0 1 1 0 1 0 2 4 15 0 2 0 2 4 2
Amphipoda (juv.) 6 0 0 0 24 0 0 0 0 0 12 0 0 0 0 11 0 0 31 17 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Anthozoa
Edwardsia sp. 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Anthozoa 2 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
Ascidiacea
Styelidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0
Styela clava 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ascidiacea 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ascidian (colonial) 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ascidian (solitary) 6 0 0 3 1 0 0 0 0 0 0 0 0 0 2 0 0 0 0 1 0 0 0 0 0 0 0 0 11 88 0 0 1 0 0
Asteroidea
Patiriella regularis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Asteroidea 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bivalvia
Anomia sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0
Anomiidae 0 1 0 0 0 0 0 0 0 0 0 1 0 0 2 0 0 0 0 0 0 0 0 0 0 0 3 1 1 3 0 1 5 0 1
Purpurocardia purpurata
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Corbula zelandica 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 1 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0
Scintillona zelandica 0 3 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Hiatella arctica 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
Arthritica bifurca 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Arthritica sp. 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
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Taxa
B1168-A
B1168-B
B1168-C
B1168-D
B1168-E
B1543-A
B1543-B
B1543-C
B1543-D
B1543-E
B1338-A
B1338-B
B1338-C
B1338-D
B1338-E
B1010-A
B1010-B
B1010-C
B1010-D
B1010-E
B1297-A
B1297-B
B1297-C
B1297-D
B1297-E
B1405-A
B1405-B
B1405-C
B1405-D
B1405-E
B1236-A
B1236-B
B1236-C
B1236-D
B1236-E
Lasaeidae 0 0 0 0 0 0 0 0 0 0 0 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Melliteryx parva 4 0 0 0 0 0 2 0 0 0 4 0 0 0 0 0 0 1 1 1 0 1 0 0 0 0 1 3 0 1 4 1 0 2 2
Limaria orientalis 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 2 0 1 2 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0
Gonimyrtea concinna 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Montacuta sp. 0 0 0 0 0 2 0 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Trichomusculus barbatus
0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Linucula hartvigiana 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 2 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0
Nuculidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Pecten novaezelandiae 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
Leptomya retiaria retiaria
1 1 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Theora lubrica 5 1 0 0 3 29 4 16 5 5 0 1 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 1 0 2 0 0 0
Diplodonta sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 2 1 0 1 2 0 0 1 2 0 1 0 0 2 0 0 0 0 0
Bassina yatei 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Dosina zelandica 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Dosinia sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0
Dosinia sp. (Juvenile) 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ruditapes largillierti 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Tawera spissa 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 1 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bivalvia indent. 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0
Bivalvia Unid. (juv) 1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Mytilidae (Juvenile) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1
Bryozoa
Bryozoa 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
Bryozoa (encrusting) 1 2 1 0 1 0 0 0 0 0 0 0 1 0 1 0 0 1 1 0 0 0 0 0 0 1 0 0 1 0 0 1 0 0 0
Bryozoa (Erect) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Bryozoa unid. 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Cirripedia
Balanus sp. 6 0 0 1 3 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0
Balanus trigonus 0 0 0 0 0 0 0 0 0 0 0 0 8 0 11 0 0 0 0 0 0 0 0 0 0 0 0 11 0 0 0 0 0 0 0
Copepoda 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0
Crustacea
Nebaliacea 1 1 0 0 3 0 0 0 0 0 0 1 1 3 7 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 1 0 0
Tanaidacea 0 0 0 1 0 0 0 0 0 0 1 0 1 0 2 0 0 0 1 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0
Mysidacea 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
Cumacea 1 0 0 0 0 0 0 1 0 2 2 0 1 0 5 1 0 0 0 0 2 0 0 0 0 0 3 1 0 0 0 0 0 0 0
Decapoda
Callianassidae 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0
Pontophilus australis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0
Diogenidae 0 0 3 0 0 0 0 0 0 0 0 0 0 18 0 0 0 10 0 0 0 0 0 0 0 0 1 1 0 0 3 0 1 0 0
Notomithrax minor 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0
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Taxa
B1168-A
B1168-B
B1168-C
B1168-D
B1168-E
B1543-A
B1543-B
B1543-C
B1543-D
B1543-E
B1338-A
B1338-B
B1338-C
B1338-D
B1338-E
B1010-A
B1010-B
B1010-C
B1010-D
B1010-E
B1297-A
B1297-B
B1297-C
B1297-D
B1297-E
B1405-A
B1405-B
B1405-C
B1405-D
B1405-E
B1236-A
B1236-B
B1236-C
B1236-D
B1236-E
Paguridae 3 3 0 0 0 0 0 0 0 0 4 0 0 0 0 1 0 0 0 0 0 0 0 0 0 11 0 0 0 1 0 0 0 0 0
Palaemon affinis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
Petrolisthes novaezelandiae
0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Liocarcinus corrugatus 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Upogebia sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0
Pilumnus novaezelandiae
0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 1 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0
Anomura 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0
Brachyura (juv.) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
Decapoda ident. 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Echinoidea
Echinocardium cordatum
0 0 0 0 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Gastropoda
Cominella adspersa 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Sigapatella novaezelandiae
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Sigapatella tenuis 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0
Pelicaria vermis vermis 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Maoricolpus roseus roseus
30 14 1 3 1 0 0 0 0 0 0 0 0 0 0 3 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
Gastropoda (micro snails)
1 1 0 0 1 0 0 0 0 0 0 0 0 0 1 0 0 6 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
Hemichordata 0 6 1 17 18 0 0 0 0 0 0 0 1 1 0 1 0 2 2 0 3 2 0 0 2 4 0 16 16 10 3 5 2 5 2
Holothuroidea
Taeniogyrus dendyi 0 3 1 2 4 0 2 0 0 2 0 0 0 0 0 0 2 2 8 2 0 3 1 0 0 1 0 2 0 0 0 0 0 1 4
Hydrozoa 1 1 0 0 1 0 0 1 0 0 1 0 0 0 1 1 0 0 1 0 0 0 0 0 1 1 0 1 1 1 0 0 1 0 0
Isopoda
Anthuridae 11 7 2 1 1 0 0 0 0 1 19 4 8 6 16 0 2 1 2 1 2 0 0 1 1 7 1 2 1 1 4 0 0 0 1
Arcturidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0
Natatolana sp. 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0
Munnidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 2 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Valvifera 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Nematoda 0 1 10 10 2 0 0 0 0 0 0 2 0 0 4 2 7 8 1 2 2 7 3 0 10 0 0 5 2 7 0 0 0 0 0
Nemertea 1 3 2 3 4 0 1 0 0 0 1 1 5 2 5 0 1 4 0 4 0 0 1 0 5 0 0 2 8 0 2 0 0 1 3
Oligochaeta 8 4 0 12 3 0 0 0 0 0 2 17 47 14 30 35 27 8 25 13 2 5 3 1 7 8 11 3 10 0 2 0 2 9 5
Ophiuroidea
Amphiuridae 36 40 18 47 16 0 1 0 0 0 19 4 3 8 6 37 17 35 81 39 15 31 1 0 5 10 15 17 7 11 9 6 14 13 20
Opisthobranchia
Philine auriformis 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0
Philine sp. 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 1 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Opisthobranchia Unid. 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
Ostrocoda
Diasterope grisea 5 2 0 0 1 1 0 1 0 4 1 0 0 0 0 1 1 0 1 0 8 2 0 0 2 0 0 1 0 1 0 1 1 0 0
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Taxa
B1168-A
B1168-B
B1168-C
B1168-D
B1168-E
B1543-A
B1543-B
B1543-C
B1543-D
B1543-E
B1338-A
B1338-B
B1338-C
B1338-D
B1338-E
B1010-A
B1010-B
B1010-C
B1010-D
B1010-E
B1297-A
B1297-B
B1297-C
B1297-D
B1297-E
B1405-A
B1405-B
B1405-C
B1405-D
B1405-E
B1236-A
B1236-B
B1236-C
B1236-D
B1236-E
Parasterope quadrata 7 1 0 1 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 4 2 0 0 0 0 0
Trachyleberis lytteltonensis
0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ostracoda 3 1 1 2 5 1 0 5 0 5 2 0 1 0 1 0 0 2 1 0 1 3 0 0 4 0 0 0 0 0 2 0 1 2 0
Phoronida 3 1 0 0 0 0 0 0 0 0 0 1 0 0 1 0 0 0 0 0 4 7 0 0 1 0 2 6 0 2 0 1 0 0 0
Platyhelminthes 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Polychaeta
Pholoidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Phyllodocida 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Ampharetidae 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 3 0
Barantolla lepte 14 14 3 6 8 0 0 1 0 0 16 8 0 4 5 9 6 13 9 4 2 7 2 0 9 8 14 8 27 13 1 1 2 2 2
Capitella sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 4 0 0 0 0 0 0 10 0 2 0 0 1 0 0 0
Capitellidae 0 1 1 0 0 0 0 0 0 0 0 1 0 2 4 0 0 6 0 0 2 1 0 0 2 0 2 0 0 0 0 0 0 1 0
Heteromastus filiformis 34 28 29 16 22 0 1 1 0 0 0 14 5 7 8 7 7 11 0 1 6 6 0 0 23 0 40 48 32 39 5 3 8 16 11
Notomastus sp. 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Phyllochaetopterus socialis
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Phyllochaetopterus sp. 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Chrysopetalidae 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Cirratulidae 38 21 8 12 0 1 1 3 1 3 0 1 0 1 0 3 2 1 0 2 2 0 1 0 2 1 2 3 0 1 0 2 2 0 3
Cossura consimilis 0 1 1 2 0 0 4 0 1 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Dorvilleidae 0 0 1 1 3 0 0 0 1 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 1 0 0 1 1 1 1 0 0 0 0
Eunice sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Glyceridae 0 0 1 2 2 0 0 0 0 0 0 1 0 1 2 1 2 0 10 0 1 0 0 1 2 0 1 5 6 1 2 0 0 1 1
Goniadidae 1 0 1 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 5 0 1 1 0 0 0 0 0 0 0
Hesionidae 3 2 3 3 2 0 1 0 0 0 3 0 1 2 1 0 1 2 4 0 1 0 0 0 1 0 0 1 2 1 0 0 1 0 0
Microphthalmus sp. 0 0 0 0 0 0 0 1 0 0 0 0 2 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Lumbrineridae 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Maldanidae 0 4 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 3 2 0 0 0 0 0 5 1 3 0 0 0 0 0
Aglaophamus sp. 0 2 2 0 1 1 1 1 2 4 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 1 0 0 0 0 0
Ceratonereis sp. 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Leonnates sp. 0 0 0 0 0 0 0 0 0 2 1 0 2 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 2 2 1
Nereididae (juvenile) 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0
Onuphis aucklandensis 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Armandia maculata 0 1 1 1 1 0 0 0 0 0 1 0 2 1 1 0 0 1 0 0 1 0 0 0 2 1 0 1 2 0 0 0 0 1 0
Orbinia papillosa 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0
Orbiniidae 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Orbiniidae juv. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0
Phylo felix 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Phylo novazealandiae 1 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Phylo sp. 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Myriochele sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 11 11 0 0 0 0 0 1 0 0 0 2 1 0 0
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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Taxa
B1168-A
B1168-B
B1168-C
B1168-D
B1168-E
B1543-A
B1543-B
B1543-C
B1543-D
B1543-E
B1338-A
B1338-B
B1338-C
B1338-D
B1338-E
B1010-A
B1010-B
B1010-C
B1010-D
B1010-E
B1297-A
B1297-B
B1297-C
B1297-D
B1297-E
B1405-A
B1405-B
B1405-C
B1405-D
B1405-E
B1236-A
B1236-B
B1236-C
B1236-D
B1236-E
Owenia petersenae 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 7 1 0 4 0 2 1 0 1 0 0 0 0 0
Aricidea sp. 1 0 0 1 1 0 0 0 0 0 2 0 0 0 2 0 3 1 1 4 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0
Paraonidae 41 23 18 24 15 0 1 0 0 0 5 7 8 12 5 21 9 11 15 2 13 13 1 0 6 4 22 16 15 33 8 6 12 19 11
Lagis sp. 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 0 0 1 0 0 0 0 0 0
Phyllodocidae 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 0 0 1 0 0
Pisionidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 1 0 0 0 0 0 0 0
Polynoidae 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Sabellariidae 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Euchone sp. 1 2 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 2 0 0 0 0 0 1 0
Sabella spallanzanii 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Sabellidae 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 0
Hydroides elegans 14 4 3 1 2 0 2 0 0 0 3 0 3 5 15 8 0 0 0 9 0 0 7 6 1 6 0 2 3 1 2 0 1 2 0
Serpulidae 3 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0
Spirorbidae 0 1 0 0 0 0 0 0 0 0 0 0 5 0 7 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
Sigalionidae 0 1 0 0 1 2 2 0 0 1 0 0 1 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Paraprionospio sp. 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Polydorid 0 0 0 0 0 2 0 12 4 5 46 13 116 12 15 1 1 0 0 0 4 67 0 1 0 171 56 8 0 1 39 2 5 30 38
Prionospio aucklandica 0 0 0 2 0 0 0 0 0 2 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Prionospio australiensis 9 2 1 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 7 0 0 0 0
Prionospio multicristata 10 4 2 5 6 0 1 0 0 2 15 14 8 6 4 0 0 1 0 0 0 1 0 0 7 0 9 11 0 1 6 0 4 4 5
Prionospio sp. 6 3 3 8 4 0 0 1 2 1 27 48 4 17 18 6 1 5 4 5 2 11 4 0 11 18 11 45 18 1 20 10 12 20 15
Prionospio tridentata 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Prionospio yuriel 0 0 0 0 0 0 2 1 0 5 0 1 0 0 0 0 0 0 0 0 2 3 0 0 0 0 1 2 0 1 0 0 0 0 1
Scolelepis sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Spiophanes kroyeri 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Exogoninae 95 28 24 73 22 0 0 0 1 0 33 11 7 8 13 47 37 49 31 23 0 10 4 0 10 0 12 26 36 11 2 0 1 3 1
Syllidae 50 24 4 17 8 0 0 0 0 0 5 2 7 9 118 19 9 25 24 9 9 0 1 4 8 1 6 16 9 4 0 0 3 0 2
Terebellidae 0 0 0 0 0 0 0 3 0 0 2 1 1 0 0 0 0 0 0 1 0 3 0 0 0 1 2 1 1 1 0 0 0 1 0
Terebellides sp. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 1 0
Polyplacophora
Leptochiton inquinatus 0 1 0 1 0 0 0 0 0 0 0 0 0 0 0 6 5 4 5 2 1 0 0 0 1 0 0 1 1 2 0 0 0 0 0
Porifera
Sycon sp. 3 0 2 2 1 0 0 0 0 0 0 0 0 0 0 0 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 2
Porifera 8 2 2 27 15 0 0 0 0 0 3 1 1 1 1 6 2 4 0 0 1 2 0 1 3 1 0 5 2 1 1 1 0 1 0
Pycnogonida 1 0 0 0 3 0 0 0 0 0 0 1 0 0 2 0 1 1 4 1 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0
Sipuncula 24 28 3 1 5 0 0 0 0 0 0 0 0 0 0 0 2 1 1 0 0 0 1 0 0 0 0 1 4 1 0 0 0 0 1
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Appendix 3. Results from SIMPER analysis of species composition similarity and dissimilarity within and between sites, respectively. Displayed are taxa that cumulatively contribute up to 50 % similarity/dissimilarity. SIMPER based on square-root abundance data.
Within sites: Site B1168 Average similarity: 59.11
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Exogoninae 6.63 5.08 5.20 8.60 8.60
Amphiuridae 5.48 4.54 5.56 7.68 16.29
Heteromastus filiformis 5.04 4.48 6.01 7.58 23.87
Paraonidae 4.84 4.15 7.52 7.03 30.90
Syllidae 4.18 2.80 3.70 4.74 35.64
Ischyroceridae 5.07 2.72 2.10 4.60 40.23
Barantolla lepte 2.90 2.25 5.63 3.81 44.04
Cirratulidae 3.41 1.92 1.15 3.24 47.28
Porifera 2.95 1.87 2.25 3.16 50.44
Site B1543 Average similarity: 35.51
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Theora lubrica 3.17 9.15 2.69 25.76 25.76
Polydorid 1.82 4.18 1.11 11.76 37.53
Cirratulidae 1.29 4.13 4.27 11.64 49.16
Aglaophamus sp. 1.28 4.08 3.71 11.50 60.66
Site B1338 Average similarity: 52.92
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Polydorid 5.70 5.03 4.13 9.51 9.51
Prionospio sp. 4.50 4.37 2.71 8.26 17.77
Oligochaeta 4.32 4.01 1.98 7.57 25.35
Exogoninae 3.63 3.77 9.42 7.12 32.46
Prionospio multicristata 2.98 3.22 3.73 6.09 38.55
Anthuridae 3.13 3.18 6.00 6.01 44.56
Paraonidae 2.68 3.10 4.86 5.86 50.41
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Site B1010 Average similarity: 57.44
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Exogoninae 6.06 6.59 7.65 11.47 11.47
Amphiuridae 6.27 6.30 5.61 10.97 22.44
Ischyroceridae 5.13 5.04 4.11 8.78 31.22
Oligochaeta 4.51 4.51 3.47 7.85 39.07
Syllidae 4.05 4.13 5.63 7.19 46.25
Paraonidae 3.24 2.99 2.69 5.21 51.47
Site B1297 Average similarity: 33.38
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Oligochaeta 1.81 3.03 3.26 9.07 9.07
Syllidae 1.77 2.33 1.04 6.99 16.06
Prionospio sp. 2.01 2.07 1.05 6.21 22.27
Paraonidae 2.13 1.92 1.00 5.74 28.02
Amphiuridae 2.54 1.90 0.97 5.68 33.70
Nematoda 1.79 1.86 1.09 5.58 39.28
Barantolla lepte 1.69 1.73 1.11 5.18 44.46
Hydroides elegans 1.22 1.67 0.43 5.00 49.46
Owenia petersenae 1.53 1.54 1.13 4.62 54.08
Site B1405 Average similarity: 48.61
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Heteromastus filiformis 5.03 4.09 1.14 8.42 8.42
Paraonidae 4.06 3.94 3.60 8.11 16.53
Barantolla lepte 3.64 3.87 5.77 7.96 24.49
Amphiuridae 3.42 3.87 4.78 7.96 32.45
Prionospio sp. 3.90 3.34 1.76 6.87 39.32
Exogoninae 3.58 2.48 1.14 5.11 44.43
Polydorid 4.88 2.27 0.62 4.66 49.09
Syllidae 2.49 2.15 3.28 4.42 53.52
Site B1236 Average similarity: 52.50
Species Av.Abund Av.Sim Sim/SD Contrib% Cum.%
Prionospio sp. 3.89 7.13 8.27 13.59 13.59
Amphiuridae 3.45 5.95 13.98 11.33 24.92
Polydorid 4.31 5.79 1.60 11.03 35.94
Paraonidae 3.28 5.70 18.43 10.85 46.80
Heteromastus filiformis 2.82 4.49 6.96 8.55 55.35
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Between sites:
Sites B1168 & B1543 Average dissimilarity = 83.49
Site B1168 Site B1543 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Exogoninae 6.63 0.20 4.91 3.64 5.88 5.88
Amphiuridae 5.48 0.20 4.11 4.01 4.92 10.81
Heteromastus filiformis 5.04 0.40 3.66 3.75 4.38 15.19
Paraonidae 4.84 0.20 3.59 5.41 4.30 19.49
Ischyroceridae 5.07 0.65 3.34 1.34 4.00 23.50
Syllidae 4.18 0.00 3.10 3.40 3.71 27.21
Porifera 2.95 0.00 2.29 1.86 2.74 29.95
Sipuncula 3.03 0.00 2.23 2.02 2.67 32.62
Barantolla lepte 2.90 0.20 2.05 3.85 2.45 35.07
Cirratulidae 3.41 1.29 1.95 2.44 2.34 37.41
Hemichordata 2.36 0.00 1.90 1.41 2.27 39.68
Theora lubrica 0.99 3.17 1.86 1.20 2.23 41.91
Maoricolpus roseus roseus 2.59 0.00 1.86 1.80 2.22 44.14
Nematoda 1.75 0.00 1.53 1.24 1.83 45.97
Oligochaeta 2.00 0.00 1.47 1.57 1.77 47.73
Polydorid 0.00 1.82 1.43 1.58 1.71 49.44
Prionospio multicristata 2.25 0.48 1.35 2.22 1.62 51.06
Sites B1168 & B1338 Average dissimilarity = 56.35
Site B1168 Site B1338 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 0.00 5.70 3.18 1.88 5.64 5.64
Ischyroceridae 5.07 3.06 2.28 1.27 4.05 9.69
Exogoninae 6.63 3.63 1.73 1.58 3.07 12.76
Cirratulidae 3.41 0.40 1.69 1.97 3.01 15.77
Sipuncula 3.03 0.00 1.61 1.92 2.86 18.63
Amphiuridae 5.48 2.67 1.57 1.97 2.79 21.42
Syllidae 4.18 4.03 1.57 1.20 2.78 24.20
Oligochaeta 2.00 4.32 1.53 1.35 2.72 26.92
Heteromastus filiformis 5.04 2.29 1.50 2.02 2.66 29.58
Prionospio sp. 2.15 4.50 1.39 1.46 2.46 32.04
Maoricolpus roseus roseus 2.59 0.00 1.35 1.68 2.40 34.44
Hemichordata 2.36 0.40 1.18 1.34 2.10 36.54
Paraonidae 4.84 2.68 1.15 2.82 2.04 38.58
Porifera 2.95 1.15 1.02 1.21 1.82 40.40
Amphipoda (juv.) 1.47 0.69 0.90 0.85 1.60 42.00
Nematoda 1.75 0.68 0.89 1.23 1.57 43.58
Anthuridae 1.88 3.13 0.85 1.59 1.51 45.09
Amphipoda 0.66 1.29 0.82 1.06 1.45 46.54
Barantolla lepte 2.90 2.21 0.72 1.26 1.28 47.81
Taeniogyrus dendyi 1.23 0.00 0.70 1.79 1.25 49.06
Balanus trigonus 0.00 1.23 0.66 0.79 1.16 50.23
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Sites B1543 & B1338 Average dissimilarity = 82.34
Site B1543 Site B1338 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Oligochaeta 0.00 4.32 4.24 2.23 5.15 5.15
Polydorid 1.82 5.70 3.76 1.21 4.57 9.72
Prionospio sp. 0.68 4.50 3.74 1.91 4.55 14.27
Syllidae 0.00 4.03 3.65 1.34 4.44 18.71
Exogoninae 0.20 3.63 3.24 3.55 3.94 22.64
Theora lubrica 3.17 0.20 2.92 1.84 3.55 26.19
Anthuridae 0.20 3.13 2.77 3.51 3.37 29.56
Ischyroceridae 0.65 3.06 2.59 0.86 3.15 32.71
Prionospio multicristata 0.48 2.98 2.49 2.24 3.02 35.73
Paraonidae 0.20 2.68 2.48 2.72 3.01 38.74
Amphiuridae 0.20 2.67 2.38 2.54 2.89 41.62
Heteromastus filiformis 0.40 2.29 2.07 1.64 2.52 44.14
Barantolla lepte 0.20 2.21 2.00 1.66 2.43 46.58
Hydroides elegans 0.28 1.91 1.63 1.49 1.98 48.55
Nemertea 0.20 1.58 1.33 1.97 1.62 50.17
Sites B1168 & B1010 Average dissimilarity = 50.10
Site B1168 Site B1010 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Heteromastus filiformis 5.04 1.92 1.67 2.25 3.33 3.33
Ischyroceridae 5.07 5.13 1.60 1.45 3.19 6.52
Oligochaeta 2.00 4.51 1.44 1.41 2.88 9.40
Cirratulidae 3.41 1.11 1.41 2.16 2.81 12.21
Amphipoda (juv.) 1.47 2.60 1.35 1.19 2.70 14.92
Sipuncula 3.03 0.68 1.22 1.39 2.43 17.35
Porifera 2.95 1.17 1.09 1.32 2.18 19.53
Maoricolpus roseus roseus 2.59 0.55 1.09 1.34 2.17 21.70
Prionospio multicristata 2.25 0.20 1.08 3.42 2.16 23.86
Hemichordata 2.36 0.77 1.07 1.35 2.14 26.00
Exogoninae 6.63 6.06 1.01 1.62 2.02 28.02
Leptochiton inquinatus 0.40 2.07 0.90 2.47 1.80 29.82
Hydroides elegans 1.98 1.17 0.89 2.40 1.78 31.60
Corophiidae 0.00 1.62 0.89 1.10 1.78 33.38
Paraonidae 4.84 3.24 0.89 1.36 1.77 35.15
Amphiuridae 5.48 6.27 0.87 1.14 1.73 36.88
Syllidae 4.18 4.05 0.85 1.42 1.69 38.58
Amphipoda 0.66 1.23 0.77 0.87 1.54 40.12
Melitidae 1.67 1.54 0.70 1.40 1.39 41.51
Prionospio australiensis 1.28 0.00 0.65 1.47 1.30 42.81
Nematoda 1.75 1.86 0.63 1.42 1.27 44.08
Ostracoda 1.48 0.48 0.57 1.54 1.15 45.23
Ampelisca sp. 1.03 0.00 0.57 1.58 1.14 46.36
Parasterope quadrata 1.13 0.00 0.56 1.45 1.12 47.48
Glyceridae 0.77 1.12 0.54 1.17 1.08 48.56
Aoridae 1.11 0.20 0.53 1.60 1.06 49.62
Anthuridae 1.88 0.97 0.53 1.14 1.05 50.68
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Sites B1543 & B1010 Average dissimilarity = 84.51
Site B1543 Site B1010 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Amphiuridae 0.20 6.27 5.52 3.97 6.53 6.53
Exogoninae 0.20 6.06 5.35 5.95 6.33 12.86
Oligochaeta 0.00 4.51 4.17 3.30 4.94 17.80
Ischyroceridae 0.65 5.13 4.07 2.84 4.81 22.61
Syllidae 0.00 4.05 3.67 5.17 4.34 26.95
Paraonidae 0.20 3.24 2.78 2.47 3.29 30.24
Theora lubrica 3.17 0.40 2.59 1.73 3.07 33.30
Barantolla lepte 0.20 2.81 2.38 3.78 2.82 36.12
Amphipoda (juv.) 0.00 2.60 2.38 1.16 2.82 38.94
Leptochiton inquinatus 0.00 2.07 1.89 4.72 2.24 41.18
Nematoda 0.00 1.86 1.71 2.47 2.02 43.20
Heteromastus filiformis 0.40 1.92 1.56 1.45 1.85 45.04
Corophiidae 0.28 1.62 1.43 1.07 1.70 46.74
Polydorid 1.82 0.40 1.42 1.64 1.67 48.41
Melitidae 0.69 1.54 1.31 1.16 1.55 49.96
Prionospio sp. 0.68 1.98 1.23 1.74 1.45 51.42
Sites B1338 & B1010 Average dissimilarity = 56.61
Site B1338 Site B1010 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 5.70 0.40 3.28 1.78 5.80 5.80
Ischyroceridae 3.06 5.13 2.49 2.34 4.40 10.20
Amphiuridae 2.67 6.27 2.25 2.04 3.97 14.17
Prionospio multicristata 2.98 0.20 1.75 3.03 3.09 17.26
Prionospio sp. 4.50 1.98 1.63 1.52 2.87 20.13
Syllidae 4.03 4.05 1.62 1.26 2.87 23.00
Exogoninae 3.63 6.06 1.60 1.94 2.83 25.82
Amphipoda (juv.) 0.69 2.60 1.54 1.15 2.73 28.55
Anthuridae 3.13 0.97 1.31 2.21 2.32 30.87
Leptochiton inquinatus 0.00 2.07 1.29 4.96 2.28 33.15
Oligochaeta 4.32 4.51 1.09 1.49 1.93 35.08
Hydroides elegans 1.91 1.17 1.04 1.56 1.84 36.91
Amphipoda 1.29 1.23 0.96 1.26 1.70 38.61
Corophiidae 1.21 1.62 0.93 1.22 1.64 40.25
Nematoda 0.68 1.86 0.87 1.54 1.53 41.78
Taeniogyrus dendyi 0.00 1.41 0.86 1.59 1.53 43.31
Heteromastus filiformis 2.29 1.92 0.85 1.22 1.50 44.81
Nebaliacea 1.28 0.00 0.79 1.53 1.40 46.21
Diogenidae 0.85 0.63 0.79 0.67 1.39 47.60
Barantolla lepte 2.21 2.81 0.74 1.19 1.30 48.90
Balanus trigonus 1.23 0.00 0.73 0.80 1.29 50.19
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Sites B1168 & B1297 Average dissimilarity = 64.68
Site B1168 Site B1297 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Exogoninae 6.63 1.66 3.38 1.85 5.23 5.23
Ischyroceridae 5.07 1.61 2.71 1.19 4.19 9.42
Heteromastus filiformis 5.04 1.94 2.35 1.39 3.64 13.06
Amphiuridae 5.48 2.54 2.32 1.34 3.59 16.65
Paraonidae 4.84 2.13 1.96 1.35 3.03 19.68
Cirratulidae 3.41 0.77 1.94 1.80 3.00 22.69
Sipuncula 3.03 0.20 1.80 1.70 2.78 25.47
Maoricolpus roseus roseus
2.59 0.00 1.63 1.69 2.53 27.99
Syllidae 4.18 1.77 1.63 1.49 2.52 30.52
Polydorid 0.00 2.24 1.38 0.75 2.13 32.65
Hemichordata 2.36 0.91 1.38 1.24 2.13 34.78
Porifera 2.95 1.03 1.37 1.15 2.12 36.90
Melitidae 1.67 0.00 1.21 1.39 1.87 38.77
Prionospio multicristata 2.25 0.73 1.20 1.87 1.85 40.62
Barantolla lepte 2.90 1.69 1.03 1.25 1.59 42.21
Nematoda 1.75 1.79 0.94 1.11 1.46 43.67
Amphipoda (juv.) 1.47 0.00 0.93 0.69 1.43 45.10
Hydroides elegans 1.98 1.22 0.90 2.00 1.40 46.50
Hesionidae 1.60 0.40 0.87 1.73 1.35 47.85
Nemertea 1.58 0.65 0.82 1.79 1.27 49.12
Prionospio australiensis 1.28 0.00 0.82 1.47 1.26 50.38
Sites B1543 & B1297 Average dissimilarity = 82.18
Site B1543 Site B1297 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Theora lubrica 3.17 0.00 5.03 1.38 6.13 6.13
Polydorid 1.82 2.24 3.18 1.29 3.87 10.00
Amphiuridae 0.20 2.54 2.81 1.36 3.42 13.42
Syllidae 0.00 1.77 2.66 1.50 3.23 16.65
Oligochaeta 0.00 1.81 2.54 3.26 3.09 19.74
Paraonidae 0.20 2.13 2.38 1.59 2.89 22.63
Hydroides elegans 0.28 1.22 2.37 0.88 2.88 25.51
Nematoda 0.00 1.79 2.23 1.62 2.72 28.23
Phoxocephalidae 1.93 0.93 2.17 1.31 2.64 30.86
Prionospio sp. 0.68 2.01 2.14 1.55 2.60 33.47
Heteromastus filiformis 0.40 1.94 2.12 1.29 2.58 36.05
Exogoninae 0.20 1.66 2.12 1.32 2.57 38.62
Ischyroceridae 0.65 1.61 2.00 1.20 2.43 41.05
Barantolla lepte 0.20 1.69 1.96 1.63 2.39 43.44
Owenia petersenae 0.00 1.53 1.83 1.81 2.23 45.67
Aglaophamus sp. 1.28 0.48 1.53 1.17 1.87 47.54
Ostracoda 1.09 0.95 1.53 1.07 1.86 49.39
Diasterope grisea 0.80 1.13 1.48 1.21 1.80 51.20
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Sites B1338 & B1297 Average dissimilarity = 63.43
Site B1338 Site B1297 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 5.70 2.24 3.91 1.45 6.17 6.17
Prionospio sp. 4.50 2.01 2.39 1.20 3.78 9.95
Ischyroceridae 3.06 1.61 2.34 0.93 3.70 13.64
Oligochaeta 4.32 1.81 2.31 1.42 3.64 17.28
Prionospio multicristata 2.98 0.73 2.03 1.63 3.21 20.49
Syllidae 4.03 1.77 2.03 0.84 3.20 23.69
Anthuridae 3.13 0.68 1.97 2.28 3.10 26.79
Exogoninae 3.63 1.66 1.79 1.20 2.83 29.62
Amphiuridae 2.67 2.54 1.59 1.48 2.51 32.12
Heteromastus filiformis 2.29 1.94 1.56 1.16 2.46 34.59
Paraonidae 2.68 2.13 1.24 1.09 1.96 36.55
Barantolla lepte 2.21 1.69 1.23 1.21 1.94 38.49
Hydroides elegans 1.91 1.22 1.17 1.44 1.85 40.34
Nematoda 0.68 1.79 1.12 1.43 1.77 42.10
Owenia petersenae 0.00 1.53 1.12 1.74 1.76 43.87
Nebaliacea 1.28 0.00 1.05 1.46 1.66 45.52
Melitidae 1.25 0.00 1.04 3.43 1.63 47.15
Phoxocephalidae 1.57 0.93 0.98 1.64 1.55 48.71
Nemertea 1.58 0.65 0.98 1.52 1.54 50.25
Sites B1010 & B1297 Average dissimilarity = 64.58
Site B1010 Site B1297 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Exogoninae 6.06 1.66 3.57 2.03 5.52 5.52
Amphiuridae 6.27 2.54 3.23 1.38 5.00 10.53
Ischyroceridae 5.13 1.61 2.99 1.52 4.63 15.16
Oligochaeta 4.51 1.81 2.22 1.69 3.44 18.60
Amphipoda (juv.) 2.60 0.00 2.04 1.12 3.16 21.76
Syllidae 4.05 1.77 1.79 1.60 2.76 24.52
Polydorid 0.40 2.24 1.49 0.78 2.30 26.83
Paraonidae 3.24 2.13 1.46 1.10 2.26 29.09
Heteromastus filiformis 1.92 1.94 1.40 1.29 2.16 31.25
Leptochiton inquinatus 2.07 0.40 1.36 2.02 2.11 33.36
Corophiidae 1.62 0.00 1.30 1.06 2.02 35.37
Melitidae 1.54 0.00 1.26 1.17 1.95 37.32
Hydroides elegans 1.17 1.22 1.14 1.15 1.76 39.08
Barantolla lepte 2.81 1.69 1.13 1.12 1.75 40.83
Owenia petersenae 0.00 1.53 1.07 1.76 1.65 42.48
Amphipoda 1.23 0.60 1.05 1.16 1.63 44.11
Prionospio sp. 1.98 2.01 0.93 1.33 1.43 45.54
Aricidea sp. 1.15 0.00 0.91 1.42 1.41 46.95
Taeniogyrus dendyi 1.41 0.55 0.89 1.35 1.38 48.34
Myriochele sp. 0.00 1.33 0.89 0.80 1.38 49.72
Nematoda 1.86 1.79 0.86 1.18 1.34 51.05
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Sites B1168 & B1405 Average dissimilarity = 53.03
Site B1168 Site B1405 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 0.00 4.88 2.95 0.90 5.57 5.57
Exogoninae 6.63 3.58 1.89 1.20 3.57 9.14
Ischyroceridae 5.07 1.96 1.88 1.11 3.55 12.69
Cirratulidae 3.41 1.03 1.48 2.09 2.79 15.48
Sipuncula 3.03 0.80 1.24 1.34 2.34 17.82
Maoricolpus roseus roseus 2.59 0.20 1.24 1.45 2.34 20.15
Heteromastus filiformis 5.04 5.03 1.20 1.04 2.26 22.42
Prionospio sp. 2.15 3.90 1.19 1.77 2.25 24.67
Amphiuridae 5.48 3.42 1.12 1.60 2.11 26.78
Syllidae 4.18 2.49 1.11 1.31 2.09 28.87
Porifera 2.95 1.13 1.08 1.22 2.04 30.91
Hemichordata 2.36 2.63 1.00 1.37 1.88 32.79
Amphipoda 0.66 1.46 0.86 1.06 1.62 34.41
Prionospio multicristata 2.25 1.46 0.85 1.84 1.60 36.01
Nematoda 1.75 1.26 0.83 1.20 1.56 37.57
Ostracoda 1.48 0.00 0.80 3.15 1.52 39.08
Ascidian (solitary) 1.04 1.23 0.77 1.26 1.46 40.54
Oligochaeta 2.00 2.21 0.77 1.10 1.46 42.00
Amphipoda (juv.) 1.47 0.00 0.76 0.70 1.44 43.44
Paraonidae 4.84 4.06 0.74 1.13 1.39 44.83
Nemertea 1.58 0.85 0.72 1.89 1.36 46.19
Melitidae 1.67 1.03 0.71 1.24 1.34 47.53
Aoridae 1.11 0.60 0.69 1.86 1.31 48.84
Atylidae 0.00 1.29 0.67 1.12 1.27 50.10
Sites B1543 & B1405 Average dissimilarity = 83.95
Site B1543 Site B1405 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 1.82 4.88 4.78 0.87 5.70 5.70
Heteromastus filiformis 0.40 5.03 4.28 1.98 5.10 10.79
Paraonidae 0.20 4.06 3.63 2.81 4.32 15.11
Barantolla lepte 0.20 3.64 3.28 3.58 3.91 19.02
Amphiuridae 0.20 3.42 3.11 3.54 3.71 22.73
Prionospio sp. 0.68 3.90 3.05 1.79 3.64 26.37
Exogoninae 0.20 3.58 2.99 1.92 3.57 29.94
Theora lubrica 3.17 0.20 2.93 1.71 3.49 33.42
Hemichordata 0.00 2.63 2.40 1.89 2.85 36.28
Syllidae 0.00 2.49 2.24 3.53 2.66 38.94
Oligochaeta 0.00 2.21 2.18 1.55 2.59 41.53
Ischyroceridae 0.65 1.96 1.43 1.54 1.71 43.24
Anthuridae 0.20 1.41 1.29 1.17 1.53 44.77
Phoxocephalidae 1.93 0.83 1.28 1.56 1.53 46.30
Prionospio multicristata 0.48 1.46 1.27 1.14 1.51 47.81
Hydroides elegans 0.28 1.32 1.21 1.14 1.44 49.25
Amphipoda 0.20 1.46 1.21 1.06 1.44 50.68
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Sites B1338 & B1405 Average dissimilarity = 52.97
Site B1338 Site B1405 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 5.70 4.88 3.15 1.36 5.94 5.94
Heteromastus filiformis 2.29 5.03 2.29 2.71 4.32 10.25
Ischyroceridae 3.06 1.96 1.62 0.90 3.06 13.32
Oligochaeta 4.32 2.21 1.62 1.46 3.05 16.36
Syllidae 4.03 2.49 1.47 0.81 2.78 19.14
Hemichordata 0.40 2.63 1.46 1.99 2.76 21.90
Prionospio sp. 4.50 3.90 1.27 1.22 2.40 24.30
Prionospio multicristata 2.98 1.46 1.23 1.41 2.33 26.63
Exogoninae 3.63 3.58 1.23 1.19 2.32 28.94
Anthuridae 3.13 1.41 1.08 1.99 2.03 30.98
Barantolla lepte 2.21 3.64 1.06 1.25 2.00 32.97
Paraonidae 2.68 4.06 1.04 1.73 1.97 34.94
Amphipoda 1.29 1.46 0.93 1.18 1.75 36.69
Balanus trigonus 1.23 0.66 0.86 0.88 1.61 38.30
Nemertea 1.58 0.85 0.85 1.79 1.61 39.91
Hydroides elegans 1.91 1.32 0.80 1.27 1.50 41.41
Ascidian (solitary) 0.28 1.23 0.79 0.91 1.48 42.89
Atylidae 0.40 1.29 0.78 1.24 1.48 44.37
Nebaliacea 1.28 0.28 0.75 1.40 1.42 45.79
Corophiidae 1.21 0.00 0.75 1.02 1.41 47.20
Diogenidae 0.85 0.40 0.73 0.68 1.39 48.59
Nematoda 0.68 1.26 0.73 1.17 1.38 49.97
Amphiuridae 2.67 3.42 0.73 1.80 1.37 51.34
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Sites B1010 & B1405 Average dissimilarity = 56.72
Site B1010 Site B1405 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 0.40 4.88 3.16 0.88 5.57 5.57
Heteromastus filiformis 1.92 5.03 2.33 2.55 4.11 9.68
Ischyroceridae 5.13 1.96 2.01 1.85 3.55 13.22
Exogoninae 6.06 3.58 1.76 1.12 3.11 16.33
Amphiuridae 6.27 3.42 1.74 1.73 3.07 19.40
Amphipoda (juv.) 2.60 0.00 1.60 1.14 2.83 22.23
Oligochaeta 4.51 2.21 1.46 1.44 2.58 24.80
Prionospio sp. 1.98 3.90 1.38 1.79 2.44 27.24
Hemichordata 0.77 2.63 1.29 1.87 2.28 29.52
Syllidae 4.05 2.49 1.10 1.37 1.94 31.47
Corophiidae 1.62 0.00 1.02 1.10 1.80 33.26
Amphipoda 1.23 1.46 0.99 1.22 1.75 35.01
Paraonidae 3.24 4.06 0.93 1.29 1.64 36.66
Hydroides elegans 1.17 1.32 0.89 1.53 1.57 38.23
Leptochiton inquinatus 2.07 0.68 0.88 1.70 1.56 39.78
Prionospio multicristata 0.20 1.46 0.84 1.05 1.48 41.26
Melitidae 1.54 1.03 0.81 1.21 1.42 42.68
Nematoda 1.86 1.26 0.77 1.29 1.35 44.04
Ascidian (solitary) 0.20 1.23 0.75 0.92 1.33 45.36
Glyceridae 1.12 1.34 0.72 1.35 1.28 46.64
Aricidea sp. 1.15 0.00 0.71 1.50 1.26 47.90
Nemertea 1.00 0.85 0.70 1.24 1.23 49.13
Atylidae 0.20 1.29 0.68 1.05 1.20 50.33
Sites B1297 & B1405 Average dissimilarity = 61.27
Site B1297 Site B1405 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 2.24 4.88 4.30 0.85 7.02 7.02
Heteromastus filiformis 1.94 5.03 3.16 1.47 5.16 12.18
Exogoninae 1.66 3.58 2.05 1.37 3.35 15.53
Prionospio sp. 2.01 3.90 2.00 1.22 3.27 18.80
Paraonidae 2.13 4.06 1.98 1.19 3.23 22.03
Amphiuridae 2.54 3.42 1.74 1.32 2.83 24.86
Barantolla lepte 1.69 3.64 1.73 1.25 2.82 27.69
Hemichordata 0.91 2.63 1.68 1.47 2.75 30.43
Ischyroceridae 1.61 1.96 1.36 1.42 2.22 32.65
Prionospio multicristata 0.73 1.46 1.13 1.06 1.85 34.50
Nematoda 1.79 1.26 1.08 1.21 1.76 36.25
Oligochaeta 1.81 2.21 1.07 1.45 1.74 37.99
Syllidae 1.77 2.49 1.02 1.42 1.67 39.66
Amphipoda 0.60 1.46 1.02 1.17 1.66 41.32
Myriochele sp. 1.33 0.20 0.96 0.88 1.57 42.89
Hydroides elegans 1.22 1.32 0.96 1.22 1.57 44.45
Ascidian (solitary) 0.00 1.23 0.94 0.78 1.53 45.98
Atylidae 0.28 1.29 0.93 1.11 1.51 47.50
Phoronida 1.13 1.06 0.90 1.25 1.46 48.96
Owenia petersenae 1.53 0.68 0.88 1.47 1.44 50.39
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Sites B1168 & B1236 Average dissimilarity = 61.60
Site B1168 Site B1236 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Exogoninae 6.63 1.03 3.64 2.78 5.91 5.91
Ischyroceridae 5.07 0.28 3.07 1.44 4.98 10.89
Polydorid 0.00 4.31 2.83 1.97 4.59 15.48
Syllidae 4.18 0.63 2.24 2.12 3.64 19.12
Cirratulidae 3.41 0.91 1.80 1.98 2.93 22.05
Sipuncula 3.03 0.20 1.77 1.74 2.88 24.93
Maoricolpus roseus roseus 2.59 0.00 1.59 1.74 2.58 27.50
Porifera 2.95 0.60 1.53 1.44 2.48 29.98
Heteromastus filiformis 5.04 2.82 1.49 1.88 2.42 32.40
Amphiuridae 5.48 3.45 1.37 1.56 2.22 34.62
Nematoda 1.75 0.00 1.27 1.26 2.06 36.68
Prionospio sp. 2.15 3.89 1.16 2.23 1.89 38.57
Melitidae 1.67 0.35 1.07 1.36 1.73 40.30
Hemichordata 2.36 1.81 1.04 1.89 1.70 41.99
Barantolla lepte 2.90 1.25 1.04 2.27 1.69 43.68
Paraonidae 4.84 3.28 1.04 1.70 1.68 45.37
Amphipoda 0.66 1.25 0.95 1.48 1.55 46.92
Hesionidae 1.60 0.20 0.95 2.61 1.54 48.45
Anthuridae 1.88 0.60 0.94 1.70 1.52 49.97
Amphipoda (juv.) 1.47 0.00 0.90 0.70 1.47 51.44
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Sites B1543 & B1236 Average dissimilarity = 79.17 Site B1543 Site B1236 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Amphiuridae 0.20 3.45 4.31 4.06 5.44 5.44
Prionospio sp. 0.68 3.89 4.29 3.40 5.42 10.87
Paraonidae 0.20 3.28 4.08 4.11 5.16 16.03
Theora lubrica 3.17 0.28 3.89 1.71 4.91 20.94
Polydorid 1.82 4.31 3.74 1.46 4.73 25.67
Heteromastus filiformis 0.40 2.82 3.19 2.61 4.03 29.70
Hemichordata 0.00 1.81 2.49 2.73 3.14 32.85
Oligochaeta 0.00 1.61 2.01 1.58 2.54 35.38
Prionospio multicristata 0.48 1.74 1.90 1.61 2.40 37.79
Phoxocephalidae 1.93 1.17 1.76 1.59 2.22 40.00
Aglaophamus sp. 1.28 0.00 1.72 3.08 2.17 42.17
Amphipoda 0.20 1.25 1.44 1.63 1.82 44.00
Melliteryx parva 0.28 1.17 1.42 1.42 1.80 45.80
Barantolla lepte 0.20 1.25 1.41 2.21 1.78 47.58
Ostracoda 1.09 0.77 1.31 1.33 1.66 49.24
Montacuta sp. 0.92 0.00 1.21 0.74 1.53 50.77
Sites B1338 & B1236 Average dissimilarity = 54.36
Site B1338 Site B1236 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Syllidae 4.03 0.63 2.56 1.06 4.72 4.72
Polydorid 5.70 4.31 2.48 1.28 4.56 9.28
Oligochaeta 4.32 1.61 2.36 1.47 4.34 13.62
Ischyroceridae 3.06 0.28 2.21 0.84 4.07 17.68
Exogoninae 3.63 1.03 2.04 2.06 3.76 21.44
Anthuridae 3.13 0.60 1.94 2.23 3.57 25.01
Prionospio sp. 4.50 3.89 1.20 1.25 2.20 27.21
Barantolla lepte 2.21 1.25 1.15 2.06 2.11 29.32
Hydroides elegans 1.91 0.77 1.13 1.38 2.07 31.40
Hemichordata 0.40 1.81 1.11 2.17 2.04 33.43
Prionospio multicristata 2.98 1.74 1.08 1.06 1.99 35.43
Diogenidae 0.85 0.55 0.99 0.75 1.82 37.25
Heteromastus filiformis 2.29 2.82 0.93 1.26 1.71 38.96
Amphiuridae 2.67 3.45 0.92 1.58 1.70 40.66
Corophiidae 1.21 0.35 0.92 1.10 1.69 42.35
Balanus trigonus 1.23 0.00 0.91 0.80 1.68 44.04
Nebaliacea 1.28 0.20 0.91 1.38 1.68 45.72
Melliteryx parva 0.40 1.17 0.89 1.57 1.63 47.35
Melitidae 1.25 0.35 0.88 2.62 1.62 48.96
Amphipoda 1.29 1.25 0.87 1.18 1.60 50.56
CAWTHRON INSTITUTE | REPORT NO. 3367 JULY 2019
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Sites B1010 & B1236 Average dissimilarity = 65.28
Site B1010 Site B1236 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Exogoninae 6.06 1.03 3.83 3.84 5.87 5.87
Ischyroceridae 5.13 0.28 3.65 3.24 5.60 11.46
Polydorid 0.40 4.31 2.89 1.82 4.43 15.89
Syllidae 4.05 0.63 2.59 2.79 3.96 19.85
Oligochaeta 4.51 1.61 2.28 1.70 3.49 23.34
Amphiuridae 6.27 3.45 2.15 1.69 3.29 26.63
Amphipoda (juv.) 2.60 0.00 1.96 1.16 3.01 29.63
Leptochiton inquinatus 2.07 0.00 1.56 4.87 2.39 32.03
Prionospio sp. 1.98 3.89 1.43 2.48 2.19 34.22
Nematoda 1.86 0.00 1.41 2.48 2.16 36.38
Prionospio multicristata 0.20 1.74 1.19 1.83 1.83 38.21
Corophiidae 1.62 0.35 1.19 1.10 1.82 40.02
Barantolla lepte 2.81 1.25 1.18 2.62 1.80 41.82
Melitidae 1.54 0.35 1.13 1.21 1.74 43.56
Amphipoda 1.23 1.25 1.11 1.80 1.70 45.26
Hydroides elegans 1.17 0.77 1.02 1.26 1.56 46.82
Heteromastus filiformis 1.92 2.82 1.01 1.39 1.54 48.37
Taeniogyrus dendyi 1.41 0.60 0.90 1.44 1.37 49.74
Hemichordata 0.77 1.81 0.82 1.30 1.26 51.00
Sites B1297 & B1236 Average dissimilarity = 63.59
Site B1297 Site B1236
Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 2.24 4.31 3.95 1.50 6.21 6.21
Amphiuridae 2.54 3.45 2.39 1.30 3.76 9.98
Prionospio sp. 2.01 3.89 2.36 1.11 3.72 13.70
Heteromastus filiformis 1.94 2.82 2.20 1.30 3.45 17.15
Paraonidae 2.13 3.28 1.97 1.04 3.09 20.24
Nematoda 1.79 0.00 1.71 1.68 2.68 22.93
Prionospio multicristata 0.73 1.74 1.60 1.34 2.52 25.45
Syllidae 1.77 0.63 1.59 1.41 2.50 27.95
Exogoninae 1.66 1.03 1.49 1.69 2.34 30.30
Hydroides elegans 1.22 0.77 1.44 1.01 2.26 32.56
Ischyroceridae 1.61 0.28 1.42 1.07 2.24 34.80
Owenia petersenae 1.53 0.00 1.42 1.78 2.23 37.02
Myriochele sp. 1.33 0.48 1.38 1.15 2.18 39.20
Hemichordata 0.91 1.81 1.28 0.95 2.02 41.22
Melliteryx parva 0.20 1.17 1.20 1.33 1.89 43.10
Phoxocephalidae 0.93 1.17 1.11 1.07 1.75 44.86
Oligochaeta 1.81 1.61 1.07 1.20 1.69 46.54
Diasterope grisea 1.13 0.40 1.02 1.20 1.61 48.15
Phoronida 1.13 0.20 1.01 1.14 1.59 49.74
Barantolla lepte 1.69 1.25 1.00 1.34 1.57 51.31
JULY 2019 REPORT NO. 3367 | CAWTHRON INSTITUTE
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Sites B1405 & B1236 Average dissimilarity = 55.84
Site B1405 Site B1236 Species Av.Abund Av.Abund Av.Diss Diss/SD Contrib% Cum.%
Polydorid 4.88 4.31 3.69 1.13 6.61 6.61
Heteromastus filiformis 5.03 2.82 2.61 3.13 4.68 11.29
Exogoninae 3.58 1.03 2.19 2.08 3.91 15.21
Barantolla lepte 3.64 1.25 1.85 2.85 3.32 18.52
Syllidae 2.49 0.63 1.46 1.90 2.62 21.15
Ischyroceridae 1.96 0.28 1.33 1.65 2.38 23.53
Prionospio multicristata 1.46 1.74 1.17 1.55 2.09 25.62
Hemichordata 2.63 1.81 1.17 2.30 2.09 27.71
Oligochaeta 2.21 1.61 1.14 1.24 2.04 29.74
Prionospio sp. 3.90 3.89 1.11 1.25 1.99 31.73
Paraonidae 4.06 3.28 1.10 1.47 1.98 33.71
Amphipoda 1.46 1.25 0.97 1.24 1.73 35.44
Ascidian (solitary) 1.23 0.20 0.94 0.90 1.68 37.12
Anthuridae 1.41 0.60 0.91 1.21 1.64 38.76
Nematoda 1.26 0.00 0.90 1.07 1.62 40.38
Atylidae 1.29 0.28 0.89 1.15 1.60 41.98
Paguridae 0.86 0.00 0.82 0.62 1.47 43.45
Nemertea 0.85 0.83 0.79 1.20 1.42 44.87
Hydroides elegans 1.32 0.77 0.78 1.07 1.40 46.26
Capitella sp. 0.92 0.20 0.75 0.81 1.35 47.61
Phoronida 1.06 0.20 0.75 1.25 1.34 48.95
Glyceridae 1.34 0.68 0.74 1.31 1.33 50.27
106 KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT
Appendix E: Survey of non-indigenous biota in the WCNP (Woods et al. 2019a).
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous
species Waitematā Harbour
Prepared for Ports of Auckland Ltd
April 2019
© All rights reserved. This publication may not be reproduced or copied in any form without the permission of the copyright owner(s). Such permission is only to be given in accordance with the terms of the client’s contract with NIWA. This copyright extends to all forms of copying and any storage of material in any kind of information retrieval system.
Whilst NIWA has used all reasonable endeavours to ensure that the information contained in this document is accurate, NIWA does not give any express or implied warranty as to the completeness of the information contained herein, or that it will be suitable for any purpose(s) other than those specifically contemplated during the Project or agreed by NIWA and the Client.
Prepared by: Chris Woods Kimberley Seaward Matt Smith
For any information regarding this report please contact: Chris Woods Marine Ecologist Marine Ecosystems and Biosecurity +64-3-348 8987 [email protected] National Institute of Water & Atmospheric Research Ltd PO Box 8602 Riccarton Christchurch 8011 Phone +64 3 348 8987
NIWA CLIENT REPORT No: 2019065CH Report date: April 2019 NIWA Project: POA19501
Quality Assurance Statement
Reviewed by: Jeanie Stenton-Dozey
Formatting checked by: Rachel Wright
Approved for release by: Helen Rouse
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Contents
Executive summary ............................................................................................................. 5
1 Introduction .............................................................................................................. 6
1.1 The survey ................................................................................................................. 6
2 Methods .................................................................................................................... 9
3 Results .................................................................................................................... 12
3.1 Non-indigenous species detected .......................................................................... 13
3.2 Specimens retained for formal taxonomic identification ....................................... 19
3.3 Native species encountered during benthic sampling ........................................... 19
4 Summary ................................................................................................................. 20
5 Acknowledgements ................................................................................................. 21
6 Glossary of abbreviations and terms ........................................................................ 22
7 References ............................................................................................................... 23
Appendix A Benthic sampling coordinates ........................................................... 24
Appendix B Benthic survey field datasheet template ........................................... 26
Appendix C Predominant sediment and habitat types at benthic sampling locations encompassing the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour ................................................................................................. 27
Appendix D Images of benthic sled contents prior to sorting ................................ 30
Tables Table 3-1: Non-indigenous marine species detected during benthic sampling in the
Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour. 13
Figures Figure 1-1: Images of Rangitoto Channel (top) and Ferguson North berth pocket area
(bottom) in Waitematā Harbour subject to dredging operations. 8 Figure 2-1: Epibenthic sled (left) and example of retrieved sled contents being examined
for marine non-indigenous species during a MHRSS survey (right). 9 Figure 2-2: Pre-allocated benthic sampling locations encompassing the Rangitoto Channel
and Ferguson North berth pocket area in Waitematā Harbour. 10
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Figure 3-1: Achieved benthic sampling locations encompassing the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour. 12
Figure 3-2: Distribution of the non-indigenous bryozoan Amathia verticillata detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. 14
Figure 3-3: Distribution of the non-indigenous crab Pyromaia tuberculata detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. 15
Figure 3-4: Distribution of the non-indigenous sabellid polychaete Sabella spallanzanii detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. 16
Figure 3-5: Distribution of the non-indigenous solitary ascidian Styela clava detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. 17
Figure 3-6: Distribution of the non-indigenous colonial ascidian Symplegma brakenhielmi detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. 18
Figure 3-7: Distribution of the non-indigenous whelk Tritia burchardi detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket in Waitematā Harbour and representative image of this organism. 19
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 5
Executive summary To assist in resource consenting for Port of Auckland development and dredging operations in Waitematā Harbour, Ports of Auckland Ltd (POAL) contracted the National Institute of Water & Atmospheric Research Ltd (NIWA) to conduct a benthic sampling survey within specific port and shipping channel areas that are to be subject to dredging operations, as well as nearby associated areas that will not be subject to dredging operations, to obtain a representative understanding of the marine non-indigenous species (NIS) present in the specified areas.
Within the Rangitoto Channel and Ferguson North berth pocket area, NIWA conducted benthic sampling at 50 discrete sampling locations. A total of six NIS were detected during benthic sampling within the Rangitoto Channel; no NIS were detected in the Ferguson North berth pocket area. The six NIS detected were as follows: 1) the bryozoan Amathia verticillata; 2) the crab Pyromaia tuberculata; 3) the sabellid polychaete Sabella spallanzanii; 4) the solitary ascidian Styela clava; 5) the colonial ascidian Symplegma brakenhielmi; and 6) the whelk Tritia burchardi. All six NIS have previously been recorded from Waitematā Harbour.
Sabella spallanzanii was the commonest NIS detected (24% detection rate compared to 2–4% for the other NIS). The six NIS detected occurred at relatively low abundance (<10 individual per 100-m benthic sled tow); these abundances are comparable to abundances detected during previous bi-monthly surveys within Waitematā Harbour for NIS as part of the Ministry for Primary Industries Marine High Risk Site Surveillance (MHRSS) programme, apart from S. spallanzanii which was detected at lower abundance compared to previous MHRSS surveys.
6 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
1 Introduction Ports of Auckland Limited (POAL) is the Auckland Council-owned company administering Auckland's commercial freight and cruise ship harbour facilities. POAL has two commercial harbours (not counting ferry terminals), with a large container and international trade port in Waitematā Harbour (Auckland) and a smaller regional port in Onehunga.
To assist in resource consenting for Port of Auckland development and dredging operations in Waitematā Harbour, POAL contracted the National Institute of Water & Atmospheric Research Ltd (NIWA) to conduct a benthic sampling survey within specific port and shipping channel areas that are to be subject to dredging operations, as well as nearby associated areas that will not be subject to dredging operations, to obtain a representative understanding of the marine non-indigenous species (NIS) present in the specified areas.
1.1 The survey The survey was a one-off sampling survey of the benthos within specific areas within the Rangitoto Channel (west of Rangitoto Island running into the Waitematā Harbour entrance) and the Ferguson North berth pocket area (within the Commercial Harbour area of Waitematā Harbour) to obtain an understanding of the NIS present in those areas, as well as nearby associated areas that will not be subject to dredging operations for comparison purposes (Figure 1-1). The survey is one component of a larger benthic ecological survey programme that POAL is undertaking.
The benthic sampling method and equipment employed for the survey are the same as those employed in the current national Marine High Risk Site Surveillance (MHRSS) programme (Woods et al. 2018). The MHRSS programme, operating since 2002 and conducted by NIWA on behalf of the Ministry for Primary Industries (MPI), is undertaken at 11 high-risk coastal locations throughout New Zealand, one of which being Waitematā Harbour. Using the MHRSS programme benthic sampling method, shown to have high NIS detection efficacy, allows comparison of results by POAL with NIS distribution and abundance sampled over 15 years in Waitematā Harbour.
The marine NIS of most concern for Waitematā Harbour are those identified by MPI as primary target pest species for the MHRSS programme; species which are listed on the Unwanted Organisms register but have not yet been detected in New Zealand.
1. The northern Pacific seastar Asterias amurensis*.
2. The European green crab Carcinus maenas*.
3. The green alga Caulerpa taxifolia*.
4. The Chinese mitten crab Eriocheir sinensis*.
5. The Asian clam Potamocorbula amurensis*.
Additionally, four secondary MHRSS programme target species are known to be established in New Zealand’s coastal waters and are all established in the Waitematā Harbour.
1. The Australian droplet tunicate Eudistoma elongatum.
2. The Asian date mussel Arcuatula senhousia.
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 7
3. The Mediterranean fanworm Sabella spallanzanii*.
4. The clubbed tunicate Styela clava.
*Notifiable organism under Biosecurity (Notifiable Organisms) Order 2016
These primary and secondary target species were of focus during the benthic survey for NIS in Waitematā Harbour. Additionally, all other marine organisms recognised by the NIWA field survey team as being NIS already established in New Zealand waters (e.g., Charybdis (Charybdis) japonica, Pyromaia tuberculata, Symplegma brakenhielmi), were also recorded if detected during the survey. Any organism not recognised by the NIWA field survey team that was suspected of being a NIS would be retained (or a representative sample thereof), preserved and sent to NIWA’s Marine Invasives Taxonomic Service (MITS, which acts as a national identification and clearing house for marine NIS in New Zealand) for expert identification.
8 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Figure 1-1: Images of Rangitoto Channel (top) and Ferguson North berth pocket area (bottom) in Waitematā Harbour subject to dredging operations. Areas subject to dredging operations are indicated in colour (colour key indicates dredging depth) and non-dredge areas are indicated as clear marked areas (Source: Ports of Auckland Ltd).
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 9
2 Methods MHRSS programme methodology for benthic sampling for NIS uses a stainless steel epibenthic sled (36 cm mouth width x 18 cm mouth height x 55 cm length (= 0.04 m2 internal volume)) with 2-mm stainless steel mesh basket (see Figure 2-1) deployed at discrete sampling locations. At each sampling location, the epibenthic sled is towed at a speed of ~2 kn for a duration of 2 min, providing a tow length of ~100 m and effective tow area of 36 m2.
Figure 2-1: Epibenthic sled (left) and example of retrieved sled contents being examined for marine non-indigenous species during a MHRSS survey (right). (Source: Chris Woods/NIWA).
The epibenthic sled is highly effective at sampling a relatively large benthic area and associated biota, including shallow-burrowing organisms (i.e., 1–2 cm substratum depth). The sled will effectively retain organisms >2 mm in size. The epibenthic sled is not designed to sample any deep-burrowing organisms (i.e., >2 cm substratum depth), biota <2 mm in size (although some of these smaller organisms some may be retained if caught/entrapped with other material in the sled), or highly mobile species (e.g., fast benthic fish), and its effectiveness is compromised in complex environments such as rocky reef or macroalgal stands (which does not typically apply for the areas concerned in this report).
Prior to the survey, 50 discrete benthic sampling locations were pre-allocated haphazardly within the Rangitoto Channel and Ferguson North berth pocket area, as well as within the shipping channel up to Wynyard Wharf (Figure 2-2), by using a grid overlaid on the survey area in Geographic Information Systems (GIS). The appropriateness of these sampling locations was confirmed with POAL prior to the survey. The coordinates for each pre-allocated sampling location were uploaded to the chart plotter of the NIWA survey boat used, allowing the skipper to accurately position the boat for sampling. Where a pre-allocated sampling point was not accessible at, or inappropriate/unsafe to sample at the time of the survey (e.g., underwater obstruction), that sampling location was relocated to a nearby location and the new coordinates recorded. Refer to Appendix A for benthic sampling location coordinates.
10 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Figure 2-2: Pre-allocated benthic sampling locations encompassing the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour.
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 11
Sampling was conducted over a two-day period (28th February and 1st March 2019). For each sampling location, the following variables were recorded as per MHRSS methodology: date of sampling; sample location identifier (location number); geographic coordinates of both start and endpoints for each benthic sled tow (latitude and longitude, as decimal degrees); boat sounder depth (m); water transparency (m); water salinity; water temperature; wind speed (kn) and direction; seabed type; habitat type; and biota of interest. Refer to Appendix B for an example of the data sheet used in the survey.
As requested by POAL, the contents of each sled tow were photographed prior to sorting to provide an additional record of biota (and associated habitat) sampled. All survey samples were then sorted onboard the NIWA survey boat in a 2 mm stainless steel mesh box sieve and any NIS detected recorded and enumerated (for both solitary and colonial organisms (as discrete colonial units for the latter) on a scale of 1–10, 10–100 or >100 organisms) on the sample data sheet against the sample location at which it was found, linking the specimen(s) to an exact location and date of collection. Native biota like the primary and secondary target NIS were also recorded and enumerated as a means of confirming that the sampling technique employed is valid for detecting like-NIS. Any organisms not recognised by the NIWA survey team but suspected of being a NIS were collected (or a representative sample thereof) for formal taxonomic identification.
Any specimen retained for formal taxonomic identification was allocated a waterproof label with a unique identifying number (the ‟sample lot code” including the identity of the survey location) and placed in an individual container for return to the NIWA laboratory. The sample lot code was then recorded on the sample data sheet against the sample in which it was found, linking the specimen to its exact location and date of collection. The sample lot code, date of collection, sample number, number of specimens retained and a description of the specimens (minimally the relevant taxon) were also recorded on a field sample register sheet, providing a list of all specimens retained during the survey.
At the end of each survey day, any specimens retained were returned to the NIWA laboratory and their labels and sample lot codes checked against the sample register. Specimens were then preserved in the chemical appropriate to that taxon, and all samples are entered in a sample record sheet, showing the number of individuals of each taxon present in that sample (as identified by the sample lot code). All specimens were then submitted to MITS as soon as practicable (shipments will need to be accompanied by Dangerous Goods documentation appropriate to the fixing and preserving chemicals used).
12 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
3 Results Benthic sampling was achieved at all 50 sampling locations (Figure 3-1). Only one sampling location, B1395, had to be re-located (to a minor extent) from its pre-allocated position due to its location in a disused cable zone.
Figure 3-1: Achieved benthic sampling locations encompassing the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour. Benthic tow starting-points are indicated with red filled circles; tow direction (and length) to endpoint is indicated by the black tail for each starting-point. Sampling location B1395 which was re-located from its original pre-allocated position is indicated in yellow.
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 13
The predominant seabed type at most locations was sand with shell hash as a secondary type, or shell hash as the predominant type (Appendix C). Most locations sampled did not appear to possess significant exposed habitat (i.e., mostly buried bivalve shells and shell hash), although some locations did possess sponge beds (B1135, B1168, B1286 and B1297, and B1183, B1405 and B1419 to a lesser extent), live large bivalves such as scallops and horse mussel (B1405) and minor ascidian beds (B1389, B1405 and B1419) (Appendix C). Refer to Appendix D for representative images of benthic sled contents prior to sorting for further clarification of seabed and habitat types encountered during benthic sampling.
3.1 Non-indigenous species detected
A total of six NIS were detected during benthic sampling within the Rangitoto Channel; no NIS were detected in the Ferguson North berth pocket area. The six NIS detected were as follows: 1) the bryozoan Amathia verticillata; the crab Pyromaia tuberculata; the sabellid polychaete Sabella spallanzanii; the solitary ascidian Styela clava; the colonial ascidian Symplegma brakenhielmi; and the whelk Tritia burchardi. All six NIS have previously been recorded from Waitematā Harbour. These species, their detection rate and location of detection are listed in Table 3-1, with their respective distributions provided in Figures 3-2 to 3-7.
Table 3-1: Non-indigenous marine species detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour.
Non-indigenous species
Common name Detection rate (% of locations sampled)
Sampling locations detected at
Amathia verticillata
Spaghetti bryozoan
4% B1361, B1389
Pyromaia tuberculata
Tuberculate pear crab
2% B1183
Sabella spallanzanii
Mediterranean fanworm
24% B1135, B1183, B1268, B1297, B1374, B1375, B1389, B1405, B1419, B1451, B1477, B1543
Styela clava Clubbed tunicate 4% B1168, B1297
Symplegma brakenhielmi
- 4% B1297, B1375
Tritia burchardi Australian dog whelk
2% B1183
Sabella spallanzanii was the commonest NIS detected (24% detection rate compared to 2–4% for the other NIS). The six NIS detected occurred at relatively low abundance (<10 individual per 100-m benthic sled tow); these abundances are comparable to abundances detected during previous MHRSS surveys within Waitematā Harbour, apart from S. spallanzanii which was detected at lower abundance compared to MHRSS surveys (e.g., it occurs at abundances up to 100 individuals per benthic sled tow in previous MHRSS surveys, source: https://www.marinebiosecurity.org.nz/).
14 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
3.1.1 Amathia verticillata The spaghetti bryozoan Amathia verticillata is a biofouling species that grows on a range of hard substratum. It is an erect, un-calcified bryozoan, with colonies made of irregularly branching stolons with particle-feeding zooids attached. Colonies may resemble masses of gelatinous noodles up to 1 m long. It can have negative impacts by clogging and fouling aquaculture and fishing gear and overgrowing and killing other sedentary species (Fofonoff et al. 2019). It was detected at two sampling locations in the Rangitoto Channel to the west of Rangitoto Island (Figure 3-2), growing on exposed shell hash. This NIS has been present in the Waitematā Harbour since 1960 and also occurs in the Bay of Islands, Whāngārei Harbour, Gulf Harbour Marina, Tauranga and Nelson harbours (source: https://www.marinebiosecurity.org.nz/).
Figure 3-2: Distribution of the non-indigenous bryozoan Amathia verticillata detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. Red filled circle = presence; blue cross = absence. Image source: C Woods (NIWA).
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 15
3.1.2 Pyromaia tuberculata The tuberculate pear crab Pyromaia tuberculata is a relatively small (typically less than 2 cm in carapace width) free-living crab whose impacts in invaded ecosystems are largely unknown (Fofonoff et al. 2018). It was detected at one sampling location in the Rangitoto Channel to the southeast of North Head (Figure 3-3), associated with exposed shell hash and small amounts of sponge. This NIS has been present in Waitematā Harbour since 2003 and also occurs in the Bay of Islands, Whāngārei, Kaipara, Manukau and Tauranga harbours and Port Taranaki (source: https://www.marinebiosecurity.org.nz/).
Figure 3-3: Distribution of the non-indigenous crab Pyromaia tuberculata detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. Red filled circle = presence; blue cross = absence. Image source: C Woods (NIWA).
16 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
3.1.3 Sabella spallanzanii The Mediterranean fanworm Sabella spallanzanii is a tube-building biofouling species that grows on a range of hard substratum, and to a lesser extent in soft substratum attached to buried hard material. It is a particle-feeding sabellid polychaete species that may grow up to almost 1 m in tube length and form dense canopy ‘forests’ and clumps of individual worms. It can have negative impacts by competing with native filter-feeding organisms for food and space, altering hydrodynamic flows, propagule recruitment, benthic biogeochemical fluxes and in high densities is likely to impact commercially important species (mussels, oysters, scallops, etc.) (e.g., Holloway and Keough 2002). This species poses a significant threat to the New Zealand aquaculture industry (Soliman and Inglis 2018); it has been detected on mussel farms near Auckland and the Coromandel Peninsula where it is subject to management control. It was detected at 24 sampling locations in the Rangitoto Channel from the top of the northern strait of the channel to southeast of North Head (Figure 3-4), growing on exposed shell hash and larger (alive and dead) bivalves (e.g., horse mussel). This NIS has been present in the Waitematā Harbour since 2009 and also occurs in a range of New Zealand locations from Whangaroa Harbour in Northland to Lyttelton Harbour/Whakaraupō in the South Island (source: https://www.marinebiosecurity.org.nz/).
Figure 3-4: Distribution of the non-indigenous sabellid polychaete Sabella spallanzanii detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. Red filled circle = presence; blue cross = absence. Image source: C Woods (NIWA).
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 17
3.1.4 Styela clava The clubbed tunicate Styela clava is a biofouling species that grows on a range of hard substratum, and to a lesser extent in soft substratum attached to buried hard material. It is a particle-feeding stalked solitary ascidian with a tough leathery body wall (often with conspicuous bumps), growing up to 20 cm long and can form dense aggregations. Like S. spallanzanii, this species can have negative impacts by competing with native filter-feeding organisms for food and space, altering hydrodynamic flows, propagule recruitment, benthic biogeochemical fluxes and in high densities is likely to impact commercially important species (mussels, oysters, scallops, etc.) (e.g., Lützen 1999, Le Blanc et al. 2007). This species poses a significant threat to the New Zealand aquaculture industry (Soliman and Inglis 2018); it has been detected on mussel farms near Auckland and the Coromandel Peninsula and has recently also been detected in several Pelorus Sound bays in the Marlborough Sounds. It was detected at two sampling locations in the Rangitoto Channel east of Takapuna Head and southeast of North Head (Figure 3-5), growing on exposed shell hash and larger (alive and dead) bivalves (e.g., horse mussel). This NIS has been present in Waitematā Harbour since 2002 and also occurs in a range of New Zealand locations from the Bay of Islands in Northland to Otago Harbour in the South Island (source: https://www.marinebiosecurity.org.nz/).
Figure 3-5: Distribution of the non-indigenous solitary ascidian Styela clava detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. Red filled circle = presence; blue cross = absence. Image source: C Woods (NIWA).
18 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
3.1.5 Symplegma brakenhielmi The colonial ascidian Symplegma brakenhielmi is a biofouling species that grows on a range of hard substratum. It is an encrusting, gelatinous ascidian, with colonies made of discrete particle-feeding zooids; the zooids do not form common systems and zooid inhalant and exhalant siphons open separately to the test surface. Colonies are often yellow, orange or maroon in colour and usually less than 10 cm in diameter. The impacts of this species in invaded ecosystems are largely unknown although its rapid growth and encrusting nature are likely to affect other encrusting biofouling species. It was detected at two sampling locations in the Rangitoto Channel to the east of St Leonards Beach and Takapuna Head (Figure 3-6), growing on exposed shell hash and bivalve shells. This NIS has been present in Waitematā Harbour since 2016, where it has rapidly spread throughout the harbour, and also occurs in Whāngārei Harbour (source: https://www.marinebiosecurity.org.nz/).
Figure 3-6: Distribution of the non-indigenous colonial ascidian Symplegma brakenhielmi detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour and representative image of this organism. Red filled circle = presence; blue cross = absence. Image source: C Woods (NIWA).
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 19
3.1.6 Tritia burchardi The Australian dog whelk Tritia burchardi is a relatively small (typically less than 1.5 cm in shell length) free-living gastropod whose impacts in invaded ecosystems are largely unknown (Townsend et al. 2010). It is a very active scavenger that may burrow into soft marine sediments. It was detected at one sampling location in the Rangitoto Channel to the southeast of North Head (Figure 3-7), associated with exposed shell hash and small amounts of sponge. This NIS has been present in Waitematā Harbour since 2009 and also occurs in the Bay of Islands and Whāngārei Harbour (source: https://www.marinebiosecurity.org.nz/).
Figure 3-7: Distribution of the non-indigenous whelk Tritia burchardi detected during benthic sampling in the Rangitoto Channel and Ferguson North berth pocket in Waitematā Harbour and representative image of this organism. Red filled circle = presence; blue cross = absence. Image source: C Woods (NIWA).
3.2 Specimens retained for formal taxonomic identification One specimen was retained for formal taxonomic identification in the field. This was a small bivalve mollusc somewhat like the primary target NIS Potamocorbula amurensis (Asian clam). This specimen was formally identified by MITS as the native Corbula zelandica.
3.3 Native species encountered during benthic sampling A range of native species that can be considered functionally like the primary and secondary target NIS were detected during benthic sampling, giving confidence to the likelihood that the sampling technique employed here would have detected these target species if they were present. These native organisms included ascidians (e.g., Synoicum kuranui), bivalves (e.g., Corbula zelandica), crabs (Halicarcinus sp., Nectocarcinus integrifrons and Notomithrax sp.) and starfish (e.g., Coscinasterias muricata and Patiriella regularis). Further detail on these native species is contained within the electronic database provided along with this report to POAL.
20 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
4 Summary Benthic sampling at 50 discrete locations within the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour detected a total of six NIS. These NIS (Amathia verticillata, Pyromaia tuberculata, Sabella spallanzanii, Styela clava, Symplegma brakenhielmi and Tritia burchardi) have previously been detected in Waitematā Harbour during previous MHRSS surveys.
No primary MHRSS target NIS were detected during sampling. Only two (Sabella spallanzanii and Styela clava) of the four secondary MHRSS target NIS were detected; the Australian droplet tunicate Eudistoma elongatum and the Asian date mussel Arcuatula senhousia were not detected, although these latter two NIS have been detected in Waitematā Harbour during previous MHRSS surveys.
Sabella spallanzanii was the commonest NIS detected (24% detection rate compared to 2–4% for the other NIS). The six NIS detected occurred at relatively low abundance (<10 individual per 100-m benthic sled tow); these abundances are comparable to abundances detected during previous bi-monthly surveys within Waitematā Harbour for NIS as part of the MHRSS programme, apart from S. spallanzanii which was detected at lower abundance compared to previous MHRSS surveys.
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 21
5 Acknowledgements Thank you to Oliver Evans, Darren Parsons and John Mark Woolley (NIWA) for assisting with the field survey. Thank you to Jeanie Stenton-Dozey for reviewing a draft of this report.
22 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
6 Glossary of abbreviations and terms GIS Geographic Information Systems
MITS Marine Invasives Taxonomic Service
NIS Non-indigenous species
NIWA National Institute of Water & Atmospheric Research Ltd
POAL Ports of Auckland Ltd
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 23
7 References Fofonoff P.W., Ruiz G.M., Steves B., Simkanin C., Carlton J.T. (2018) National Exotic Marine
and Estuarine Species Information System. http://invasions.si.edu/nemesis/. Access Date: 26-Mar -2019.
Fofonoff P.W., Ruiz G.M., Steves B., Simkanin C., Carlton J.T. (2019) National Exotic Marine and Estuarine Species Information System. http://invasions.si.edu/nemesis/. Access Date: 26-Mar -2019.
Holloway, M.G., Keough, M.J. (2002) An introduced polychaete affects recruitment and larval abundance of sessile invertebrates. Ecological Applications, 12(6): 1803–1823.
Le Blanc, A.R., Bourque, D., Landry, T., Davidson, I., MacNair, N.G. (2007) The predation of zooplankton by the blue mussel (Mytilus edulis) and the clubbed tunicate (Styela clava). Canadian Technical Report of Fisheries and Aquatic Sciences, 2684: 18 p.
Lützen, J. (1999) Styela clava Herdman (Urochordata, Ascidiacea), a successful immigrant to North-West Europe: ecology, propagation and chronology of spread. Helgolander Meeresun, 52: 383–391.
Soliman, T., Inglis, G.J. (2018) Forecasting the economic impacts of two biofouling invaders on aquaculture production of greenlipped mussels Perna canaliculus in New Zealand. Aquaculture Environment Interactions, 10: 1–10.
Townsend, M., Marshall, B.A., Greenfield, B.L. (2010) First records of the Australian dog whelk, Nassarius (Plicarcularia) burchardi (Dunker in Philippi, 1849) (Mollusca: Gastropoda) from New Zealand. New Zealand Journal of Marine and Freshwater Research, 44(4): 343-348, DOI: 10.1080/00288330.2010.511676.
Woods, C., Seaward, K., Pryor Rodgers, L., Inglis, G. (2018) Marine High Risk Site Surveillance Programme: Annual Synopsis Report for all High Risk Sites 2017–18 (SOW18048). MPI Technical Paper No: 2018/45. 34 p. + Appendices. ISBN No: 978-1-77665-943-2 (online).
24 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Appendix A Benthic sampling coordinates Note: Sampling location B1395 which was re-located from its original pre-allocated position during field work is indicated in yellow highlight.
Sampling location Start latitude Start longitude End latitude End longitude
B1001 -36.840687 174.789497 -36.83951 174.78831
B1006 -36.839887 174.78275 -36.83848 174.78297
B1008 -36.839854 174.784992 -36.8396 174.78679
B1010 -36.83982 174.787234 -36.83812 174.78648
B1020 -36.839651 174.798444 -36.83899 174.80037
B1037 -36.838868 174.790576 -36.83746 174.79111
B1041 -36.838801 174.79506 -36.83722 174.79422
B1047 -36.838699 174.801786 -36.83786 174.80321
B1050 -36.838648 174.805149 -36.83831 174.80679
B1057 -36.838153 174.778225 -36.83865 174.77962
B1060 -36.838102 174.781588 -36.83938 174.78073
B1100 -36.837151 174.78493 -36.83752 174.7869
B1107 -36.836795 174.80847 -36.83568 174.8071
B1119 -36.836401 174.77482 -36.83635 174.77626
B1125 -36.8363 174.781546 -36.83632 174.78346
B1135 -36.835826 174.812932 -36.83464 174.81166
B1149 -36.835583 174.769194 -36.83573 174.77062
B1168 -36.834805 174.820757 -36.83431 174.82293
B1171 -36.834799 174.761327 -36.83454 174.76284
B1183 -36.833955 174.817373 -36.83329 174.81906
B1200 -36.832067 174.822935 -36.83254 174.8211
B1211 -36.830231 174.825134 -36.83165 174.82561
B1218 -36.829278 174.828475 -36.82834 174.82958
B1236 -36.82564 174.830631 -36.81966 174.83327
B1258 -36.8211 174.832765 -36.81705 174.83084
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 25
Sampling location Start latitude Start longitude End latitude End longitude
B1268 -36.818431 174.830459 -36.8136 174.83039
B1286 -36.81481 174.831494 -36.82419 174.83168
B1297 -36.812159 174.828067 -36.81232 174.8305
B1314 -36.808572 174.826861 -36.80727 174.82678
B1321 -36.806822 174.823457 -36.80538 174.82369
B1338 -36.803252 174.821131 -36.80179 174.82099
B1350 -36.800583 174.818826 -36.79916 174.81891
B1361 -36.797931 174.815401 -36.79644 174.81494
B1374 -36.795246 174.814217 -36.7936 174.81412
B1375 -36.794396 174.810834 -36.79304 174.81095
B1389 -36.791693 174.810771 -36.79218 174.81271
B1395 -36.79013 174.80985 -36.79105 174.80849
B1405 -36.787256 174.806184 -36.78756 174.8082
B1419 -36.784536 174.80724 -36.78536 174.80554
B1434 -36.780949 174.806036 -36.7797 174.80863
B1451 -36.777293 174.809311 -36.77586 174.80971
B1467 -36.773655 174.811467 -36.77417 174.80958
B1477 -36.771802 174.814784 -36.77059 174.81562
B1490 -36.768181 174.815819 -36.76905 174.8143
B1505 -36.764525 174.819094 -36.76602 174.81801
B1516 -36.761788 174.82127 -36.76275 174.81965
B1522 -36.760835 174.824608 -36.76178 174.82313
B1533 -36.758098 174.826783 -36.75926 174.82539
B1543 -36.755378 174.827839 -36.75661 174.8264
B1555 -36.75264 174.830014 -36.75404 174.82888
26 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Appendix B Benthic survey field datasheet template Note: sediment type = seabed type; shelly gravel = shell hash.
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 27
Appendix C Predominant sediment and habitat types at benthic sampling locations encompassing the Rangitoto Channel and Ferguson North berth pocket area in Waitematā Harbour Seabed type categories: Sandy mud; Muddy sand; Sand; Sandy gravel; Shell hash; Sand foul; Sand reef; Reef; Other (Please state); and Mud. Habitat type categories: Seagrass bed; Oyster bed (Pacific or Flat oysters); Horse mussels; Scallops; Large bivalves (Cockles, Pipis or Others); Algae, Sponge bed; and Nothing. Secondary (i.e., present but to a lesser extent) category variables are indicated in brackets ().
Sampling location
Seabed type1 Habitat type
B1001 Sand (Shell hash) Nothing
B1006 Sand Nothing
B1008 Other – hard clay Nothing
B1010 Sand (Shell hash, Other – hard clay)
Nothing
B1020 Sand Nothing
B1037 Sand (Shell hash) Nothing
B1041 Sand (Shell hash) Nothing
B1047 Sand Nothing
B1050 Sand (Shell hash) Nothing
B1057 Sand Nothing
B1060 Sand (Shell hash) Nothing
B1100 Sand Nothing
B1107 Sand (Shell hash) Nothing
B1119 Sand Nothing
B1125 Sand Nothing
B1135 Sand (Shell hash) Sponge bed
B1149 Sand Nothing
B1168 Sand (Shell hash) Sponge bed
B1171 Sand Nothing
1 In some instances, seabed sediment collected in the benthic sled during the tow sample may not be retained in the sled during retrieval (i.e., it may be washed out through to the sled’s 2-mm mesh whilst being hauled back up to the boat).
28 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Sampling location
Seabed type1 Habitat type
B1183 Sand (Shell hash) Nothing (small amount of sponge)
B1200 Sand (Shell hash) Nothing
B1211 Sand (Shell hash) Nothing
B1218 Sand Nothing
B1236 Sand (Shell hash) Nothing
B1258 Sand (Shell hash) Nothing
B1268 Sand (Shell hash) Nothing
B1286 Sand Sponge bed
B1297 Sand (Shell hash, Other – hard clay)
Sponge bed
B1314 Sand (Shell hash) Nothing
B1321 Shell hash Nothing
B1338 Shell hash Nothing
B1350 Shell hash Nothing
B1361 Muddy sand (Shell hash) Nothing
B1374 Sand (Shell hash) Nothing
B1375 Sand (Shell hash) Nothing
B1389 Shell hash Small number of ascidians
B1395 Sand (Shell hash) Nothing
B1405 Sand (Shell hash) Scallops (live), horse mussel and small number of sponges and ascidians
B1419 Sand (Shell hash) Small amount of sponge and ascidians
B1434 Muddy sand (Shell hash) Nothing
B1451 Sand (Shell hash) Nothing
B1467 Sand (Shell hash) Nothing
B1477 Sand (Shell hash) Nothing
B1490 Sand (Shell hash) Nothing
B1505 Sand (Shell hash) Nothing
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 29
Sampling location
Seabed type1 Habitat type
B1516 Muddy sand (Shell hash) Nothing
B1522 Sand (Shell hash) Nothing
B1533 Sand (Shell hash) Nothing
B1543 Sand (Shell hash) Nothing
B1555 Sand (Shell hash) Nothing
30 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
Appendix D Images of benthic sled contents prior to sorting Note: these images are lower resolution versions of original (higher resolution) images provided to POAL separately.
B1001 B1006
B1008 B1010
B1020 B1037
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 31
B1041 B1047
B1050 B1057
B1060 B1100
B1107 B1119
32 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
B1125 B1135
B1149 B1168
B1171 B1183
B1200 B1211
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 33
B1218 B1236
B1258 B1268
B1286 B1297
B1314 B1321
34 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
B1338 B1350
B1361 B1374
B1375 B1389
B1395 B1405
Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species 35
B1419 B1434
B1451 B1467
B1477 B1490
B1505 B1516
36 Benthic sampling of Rangitoto Channel and Ferguson North berth pocket for marine non-indigenous species
B1522 B1533
B1543 B1555
109 KENNEDY ENVIRONMENTAL LIMITED
RANGITOTO CHANNEL DREDGING ENVIRONMENTAL ASSESSMENT