Wheatstone Project - Chevron Corporation · 2018. 3. 1. · Chevron Australia (See Condition 39 regarding Chevron Australia’s response). Prof. Marsh has also endorsed by letter,

© Chevron Australia Pty Ltd

Document No: WS0-0000-HES-PLN-CVX-000-00065-000 Revision: 7

Revision Date: 12 August 2014

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Wheatstone Project Dugong Research Plan

Wheatstone Project Document No: WS0-0000-HES-PLN-CVX-000-00065-000 Dugong Research Plan Revision: 7 Revision Date: 12/08/2014

© Chevron Australia Pty Ltd Public Page 1

Printed Date: 12/11/2014 Uncontrolled when printed

TABLE OF CONTENTS

ACONYMS, ABBREVIATIONS AND TERMINOLOGY .......................................................... 3

1.0 INTRODUCTION ............................................................................................................ 5

2.0 DUGONG RESEARCH PLAN ........................................................................................ 8

2.1 Background ........................................................................................................... 8 2.2 Scope of Work ....................................................................................................... 9 2.3 Manned Aerial Surveys ......................................................................................... 9

2.3.1 Objectives ................................................................................................ 9 2.3.2 Overview .................................................................................................. 9 2.3.3 Survey Methods ..................................................................................... 11 2.3.4 Data Analysis ......................................................................................... 12

2.4 Seagrass Surveys ............................................................................................... 13 2.4.1 Objectives .............................................................................................. 13 2.4.2 Overview ................................................................................................ 13 2.4.3 Survey Methods ..................................................................................... 13

2.5 Satellite Tagging .................................................................................................. 14 2.5.1 Objectives .............................................................................................. 14 2.5.2 Overview ................................................................................................ 14 2.5.3 Tagging Methods ................................................................................... 15 2.5.4 Data Analysis and Movement Determination ........................................ 15

2.6 Spatially Explicit Population Modelling ................................................................ 16 2.6.1 Objectives .............................................................................................. 16 2.6.2 Overview ................................................................................................ 16 2.6.3 Data analysis ......................................................................................... 16

2.7 Passive Acoustics ............................................................................................... 16 2.8 Salvage and Necropsy of Dead Dugongs (Dugong dugon) ................................ 17

2.8.1 Background ........................................................................................... 17 2.8.2 Dugong Salvage and Necropsy Guidelines ........................................... 17 2.8.3 Implementation of Guidelines ................................................................ 17

2.9 Determining Impacts: Data analysis and limitations ............................................ 17 2.9.1 Limitations ............................................................................................. 18 2.9.2 Potential Biological Removal ................................................................. 18 2.9.3 Project Management, Statistical Advice and Project Personnel ............ 19 2.9.4 Peer Review .......................................................................................... 19 2.9.5 Deliverables and Schedule .................................................................... 19 2.9.6 Review, Approval and Revision of this Plan .......................................... 20

2.10 References .......................................................................................................... 21




TABLES

Table 1: Where Specific Conditions are discussed in the Dugong Research Plan .................. 5

FIGURES

Figure 2.1: Survey Area proposed for Aerial Surveys ............................................................ 11




ACONYMS, ABBREVIATIONS AND TERMINOLOGY

BACI Before-After/Control-Impact

Chevron Australia Chevron Australia Pty Ltd

CPCe Coral Point Count with Excel extensions

Cth Commonwealth

DDSPEMMP Dredging and Dredge Spoil Placement Environmental Monitoring and Management Plan

Domgas Domestic Gas

DPaW Department of Wildlife and Parks (WA) - formerly Department of Environment and Conservation (WA)

Draft EIS/ERMP The Environmental Impact Statement/Environmental Review and Management Programme

DRP Dugong Research Plan

DTAP Dredge Technical Advisory Panel

DOTE Department of the Environment - formerly Department of Sustainability, Environment, Water, Population and Communities (Cth)

DNA Deoxyribonucleic acid

EP Act (WA) Environmental Protection Act 1986

EPBC Ref 2008/4469 The Commonwealth Primary Environmental Approval and conditional requirements for the Wheatstone Project. Commonwealth Government of Australia, Minister for Sustainability, Environment, Water, Populations and Communities, Hon. Tony Burke, 22 September 2011, with variations to EPBC 2008/4469 conditions 44, 45, 55, 56 and 66 made pursuant to section 143 of the EPBC Act, as amended from time to time.

GIS Geographic Information System

GPS Global Positioning System

Ha hectare(s)

JCU James Cook University

Km kilometre(s)

LNG Liquefied Natural Gas

M metre(s)

MUCRU Murdoch University Cetacean Research Unit

Nearshore Marine habitat from the 20 m contour to the shoreline

Nm nautical mile(s)

Offshore Marine habitat beyond the 20 m contour to the shoreline

PBR Potential Biological Removal

(The) Plan Dugong Research Plan




Practicable Means reasonably practicable having regard to, among other things, local conditions and circumstances (including costs) and to the current state of technical knowledge (taken from the EP Act)

Project Nearshore and offshore marine facilities, trunkline, and Onshore Facility

Project area Refers to an area bounded by Tortoise Island to the west, Thevenard Island to the North and SW Twin Island to the east. This area encompasses most mapped seagrass areas predicted to be influenced by the dredge plume.

TDR Time-depth Recorder

WA Western Australia




1.0 INTRODUCTION

In September 2011 the Commonwealth Minister for Sustainability, Environment, Water, Population and Communities granted conditional approval of the Wheatstone Project (EPBC 2008/4469). Condition 37 ‘Dugong Research Plan’ stated: “The person taking the action must develop and submit to the Minister for approval, a Dugong Research Plan (DRP).”

This document fulfils the Commonwealth requirement for a DRP. The DRP consists of the following:

Section 1.0: Introduction and summary of actions, where applicable, relating to Conditions 37 to 43

Section 2.3 to Section 2.7: Research proposal to achieve Conditions 37a to 37d

Section 2.8: Proposed approach to undertake salvage and necropsy of dead dugongs to achieve Condition 37e.

Table 1 lists all conditions relating to the DRP, a summary of actions relating to each condition and how and where they are discussed in this document.

Table 1: Where Specific Conditions are discussed in the Dugong Research Plan

Condition Summary of action Document Reference

37. The person taking the action must develop and submit to the Minister for approval, a Dugong Research Plan (DRP). The DRP must consider the following:

This document.

a. Methodology for pre-, during-, and after-dredging aerial surveys of the coastline between (and including) Exmouth Gulf and north of Yammadery Island, extending at least 30 kilometres from the coastline and taking into account potential changes in seasonality of distribution.

This methodology was considered appropriate for this Project.

Section 2.3

b. Methodology for using dugong sightings, within the predicted zone of moderate impact as identified in the final Environmental Impact Statement, to sample for seagrass.

Towed or drop down cameras will be used to survey seagrasses in areas where dugongs are sighted during the aerial survey and based on observations during the tagging study. Note that this approach will now replace the sidescan survey approach originally proposed in the first draft of the DRP.

Section 2.4

c. Methodology for using satellite tagging to identify the presence of important feeding habitat in the Project area, the size of

This methodology was considered appropriate for this Project, but will require ethics approval and a health and safety assessment. It will be

Section 2.5





home ranges and any identifiable changes in behaviour or distribution before, during and after dredging.

trialled under Phase 1. If successful it will be considered for Phase 2.

d. Methodology for using Passive Acoustic Monitoring to detect the location and number of feeding dugongs.

This methodology was considered inappropriate for this Project. See Section 2.0 for justification for rejection of this approach.

Section 2.7

e. Methodology for opportunistic research via dugong salvage and necropsy.

This approach is considered appropriate in the event that a dead dugong is found in the Project area. As previously reported to the Commonwealth, Chevron Australia will adopt salvage and necropsy procedures recommended by Eros et al. (2007) in the manual Procedures for the Salvage and Necropsy of the Dugong (Dugong dugon). This manual is published by the Great Barrier Reef Marine Park Authority.

Eros, C., Marsh, H., Bonde, R., O’Shea, T., Beck, C., Recchia, C., Dobbs, K., Turner, M., Lemm, S., Pears, R. and Bowater, R. 2007. Procedures for the Salvage and Necropsy of the Dugong (Dugong dugon) - Second Edition. Research Publication No. 85. Published by the Great Barrier Reef Marine Park Authority.

Section 2.8

38. The DRP must be reviewed and endorsed by an independent scientific expert with proven expertise in dugong tagging, satellite tracking and aerial surveys for dugong.

Prof. Helene Marsh, James Cook University, reviewed the proposal and provided her recommendations to Chevron Australia (See Condition 39 regarding Chevron Australia’s response). Prof. Marsh has also endorsed by letter, dated 20 May 2012, the DRP.

NA

39. The person taking the action must provide to the Minister, a copy of all the recommendations made by the independent dugong scientific expert and an explanation of how these recommendations have, or will be implemented or an explanation of why the person taking the action does not propose to implement certain recommendations. This information must be provided to the Minister within one month of receiving advice from the independent

Chevron Australia has provided to the Minister a copy of the recommendations and Chevron Australia’s response by letter dated 20 May 2012.

NA





dugong scientific expert or within any timeframe recommended by the independent dugong scientific expert, should this be less than one month.

40. The DRP must be submitted for approval by the Minister no later than 3 months from the date of this approval, unless otherwise approved by the Minister.

The first draft was submitted 22 December 2011.

NA

41. The results of the DRP must be used to inform an adaptive management response, as applicable, to manage potential impacts to dugong or their habitat and be taken into consideration in revisions of the DDSPEMMP, referred to at Condition 10.

The results will be used to inform an adaptive management response in relation to dugongs and or their habitat during dredging. The mechanism for this will be via the Dredge Technical Advisory Panel (DTAP). A member of the DTAP will be a dugong/seagrass expert who will review the findings of the Plan and provide recommendations to Chevron Australia.

NA

42. The DRP must be reviewed and revised on the recommendation of the independent scientific dugong expert and submitted to the Minister for approval. The approved DRP must be implemented.

Where appropriate the recommendations of the reviewer have been adopted. In some cases, the decision to modify the Plan will be deferred until the end of Phase 1 (baseline study) as recommended by the reviewer. This will be done, in part, based on advice from the DTAP and the research team.

NA

43. The approved DRP must be implemented.

NA




2.0 DUGONG RESEARCH PLAN

2.1 Background

Chevron Australia Pty Ltd (Chevron Australia) will construct and operate a multi-train Liquefied Natural Gas (LNG) and domestic gas (Domgas) plant near Onslow on the Pilbara Coast, Western Australia. The Wheatstone Project (the Project) will process gas from various offshore fields in the West Carnarvon Basin. Ashburton North Strategic Industrial Area is the approved site for the LNG and Domgas plants.

The dredge plume modelling predicts that temporary impacts are likely to be greater than any impacts from the direct removal of seagrass (Chevron, 2011). Up to 10 ha of seagrass habitat could be directly removed through the creation of the trunkline. Chevron Australia modelled plume flow to predict zones of impact for seagrasses based on their tolerance to sedimentation and increased turbidity. The total estimated area of seagrass which is likely to experience partial mortality (up to 50%) is 2963 ha – approximately 20% of the total seagrass in the project area.

Little is known about the use of the Project area by dugongs. One aerial survey of the Pilbara region was conducted by Prince et al. (2001) in 2000 and the estimated population abundance for the Region was 2046 (± 376 se). Consequently the region was considered “an integral part of the resource areas sustaining dugong presence on the Western Australian coast” (Prince et al., 2001). The Exmouth Gulf, immediately south of the Wheatstone area has been systematically surveyed by the Department of Parks and Wildlife (DPAW) (formerly Department of Environment and Conservation) for dugongs four times since 1989 and estimates have ranged from 704 (± 354 se) to 1062 (± 321 se) dugongs for the Gulf alone (Hodgson, 2007). However, during Prince et al.’s survey in April 2000, there were very few dugongs sighted with Exmouth Gulf, and this was considered a result of a cyclone in March 1999 having damaged a large proportion of the seagrass beds. An increase in the population was noted by Gales et al. (2004) which led them to suggest that dugongs had moved from Exmouth to Shark Bay until the seagrass recovered in the Gulf. Aerial surveys targeting humpback whales were conducted throughout the Project area on a monthly basis from May 2009 to April 2010 and dugong sightings were also recorded (Jenner et al., 2010). Dugong numbers appeared to fluctuate throughout the year, with the highest numbers recorded in July. The most recent survey in the region, covering part of Exmouth Gulf and the Project area, were conducted in August 2010. The population abundance estimate for the Wheatstone area was 287 (95% CI: 176–340) and for Exmouth Gulf was 1760 (95% CI: 1,369–2,088) (RPS, 2010).

The Prince et al. (2001) and RPS (2010) surveys comprise our entire knowledge of dugongs in the Project area. The levels of, and potential reasons for, seasonal fluctuations in dugong numbers off Onslow and through the surrounding region, are undocumented. As a consequence of this paucity of knowledge, Condition 37 of EPBC 2008/4469 specifies that a DRP be developed to better understand the importance of the Project area for dugongs. The findings of this research must be considered as part of the Dredging and Dredge Spoil Placement Environmental Monitoring and Management Plan (DDSPEMMP). Should dugongs be found to utilise habitat other than the mapped seagrass beds, it is a requirement of the conditions that these areas be adaptively managed and mitigation measures are developed and implemented via the DDSPEMMP.




2.2 Scope of Work

Three phases have been identified as part of the DRP:

Phase 1 – one-year pre-dredging study of dugongs (1 year)

Phase 2 – during dredging study of dugongs (assuming 3 years)

Phase 3 – post-dredging studies of dugongs (1 year).

This document provides an outline of the research to be conducted during all three phases, developed by the Murdoch University Cetacean Research Unit (MUCRU), in collaboration with external experienced researchers.

There are three main research techniques proposed:

1. Manned aerial surveys – providing broad scale data on dugong distribution and abundance from Exmouth Gulf to Barrow Island.

2. Satellite tagging – providing detailed information about individual dugong habitat use, movements and behaviour.

3. Population modelling – value adding to aerial survey data by using dugong distribution and relative density throughout the survey area to determine the relative conservation value of the area for dugongs.

The above techniques address methods suggested within Conditions 37a and 37c of the proposed approval (EPBC 2008/4469). This document also outlines the way in which Condition 37b, d and e will be addressed; these methods will be conducted by research groups / consultants other than MUCRU.

2.3 Manned Aerial Surveys

2.3.1 Objectives

Provide a relative estimate of the abundance of dugongs around the Onslow area (from Exmouth Gulf to Barrow Island), and the distribution of dugongs throughout this area, immediately before, during, and after the undertaking of major marine activities relating to the Project (i.e. during Phases 1, 2 and 3).

Investigate the seasonal variation in dugong abundance and distribution during the summer, autumn, winter and spring during Phase 1 of the Wheatstone Project.

Determine the seasonal variation in dugong numbers between two select times of year during Phases 2 and 3 of the Wheatstone Project.

2.3.2 Overview

Aerial surveys are one of the most established and reliable techniques for determining dugong abundance, distribution, and habitat use. Aerial surveys provide a broad-scale snapshot of dugong distribution within the surveyed region, and dugongs have been routinely surveyed using this method for a number of decades in many sites around Australia (Holley et al., 2006, Grech et al., 2011). The datasets produced from dugong aerial surveys have formed the basis for developing dugong density models to predict critical habitat areas and conduct risk assessments of human impacts (Grech and Marsh, 2007, Grech and Marsh, 2008, Grech et al., 2011).




Chevron Australia will, as far as practicable, survey dugongs following the standardised methods established by Marsh and Sinclair (1989a) and Pollock et al. (2006). As it is critical to obtain reliable data, we will use experienced dugong aerial survey observers. We will follow the flight plan (i.e. transect layout) of the aerial surveys conducted regularly by DPAW in Exmouth Gulf (four surveys since 1989), to obtain a measure of density within the Gulf that can be compared to previous years (Hodgson et al., 2008). This flight plan has been extended to include the Onslow area and provide relative abundance estimates for the area north of Onslow to Barrow Island (Figure 2.1), and for the area north of Exmouth, will follow the flight plan used by Prince et al. (2001). The northern part of the survey area is designed to encompass an area of high dugong density around Barrow Island (Prince et al., 2001). The survey methods and analysis for the entire aerial survey will follow the standardised methods described by Marsh and Sinclair (1989a, 1989b), followed by Prince et al. (2001) and updated by Pollock et al. (2006).

As discussed in the Background section of this document, the population of dugongs in Exmouth Gulf has varied over the last two decades as a result of Cyclone Vance destroying the seagrass beds in the Gulf in 1999 (Gales et al., 2004). The latest survey of the entire Gulf, conducted in 2007, showed that dugong numbers had increased again in Exmouth Gulf (Hodgson, 2007). All surveys by DPAW are conducted in June/early-July to coincide with seasonally low wind conditions. Data from the Jenners’ whale surveys in the Onslow region suggest that these months are also the months when dugong numbers peak in the area (Jenner et al., 2010). These surveys are designed to investigate the seasonal variation suggested in Jenner et al. (2010) throughout Phase 1 (the one-year pre-dredging phase) associated with the Wheatstone Project, and to determine whether movements of dugongs north or south of the Onslow area can explain this variation. During Phases 2 and 3 of the development, Chevron Australia has been advised to conduct the same surveys twice yearly, at times to be determined according to the results of Phase 1.




Figure 2.1: Survey Area proposed for Aerial Surveys

2.3.3 Survey Methods

Aerial surveys will be conducted four times to cover seasonal variations in rain patterns during Phase 1, and at two selected time periods (according to results from Phase 1) during Phases 2 and 3. The timing of the Phase 1 surveys take into consideration historical weather data and tidal information, i.e. the final schedule will be based on rainfall and wind information and will be designed to avoid high winds and spring tides.

Phase 1 data will be considered the ‘before impact’ data during this research project. As this Phase is constrained to one year, and as the aim is to assess potential seasonal variation in dugong abundance, it is important to be able to distinguish between across-survey variation versus across-season variation. For this purpose the study will incorporate within survey replication of a sub-set of survey transects. The subset of transects will be those that cover the predicted zone of impact within the Wheatstone area as defined in Figure 2.1.

Dugongs will be the main focus of the surveys and therefore the survey design maximises detection of this species. However, other species of marine megafauna will also be counted, including whales, dolphins, turtles, sharks and sea snakes. Observers will fly along parallel line transects spaced at intervals of 2.5 nm (4.6 km), using a Partenavia high-wing six-seater aircraft. A transect strip of 200 m will be delineated on each side of the plane using marker poles attached to pseudo wing-struts (Marsh and Sinclair, 1989a). These markers will be calibrated on the ground to account for the eye height of individual observers. The surveys will be flown at a height of 500 ft (152 m), providing a survey intensity of 9-10%.




The survey team will consist of four dedicated observers and a survey leader. The two primary observers will be seated in the middle seats and the two secondary observers in the rear seats. The observers and the survey leader will communicate via aviation headsets connected to two intercoms, so that the secondary observers are isolated acoustically from the primary observers. Each intercom will be connected to a separate track of a two-track digital voice recorder. This arrangement allows the sightings of the two observers on each side of the aircraft to be independent and perception bias to be calculated as explained below. It is essential that observers meet the weight (<70 kg) and meet the computer literacy requirements.

The survey leader will enter all sightings called by the primary observers into a pocket computer using a specialised program developed for dugong aerial surveys. For each animal group sighted, recordings are taken of the total number of animals visible, along with the number of animals at the surface, position in the transect, and turbidity. For dugongs and dolphins, the number of calves is also recorded. Dolphins and whales will be identified to species where possible and observers will be asked to assess how sure they are of the species (certain, probable or guess). All dugong groups of greater than 10 animals, whether inside or outside of the transect strip, are circled and counted, and then the transect is resumed.

The survey leader will also enter data on environmental conditions at the beginning of each flight (cloud cover, cloud height, wind speed, wind direction and air visibility) and each transect (cloud cover). Periodically during each transect, and whenever conditions change, the survey leader will record Beaufort sea state, turbidity, and glare on each side (scored by the observers).

2.3.4 Data Analysis

Analysis of sighting data to determine population estimates of dugongs from Exmouth Gulf to Barrow Island will follow methods developed by Marsh and Sinclair (1989a), and further modified by Pollock et al. (2006). These methods allow estimates to be calculated using correction factors which account for availability bias (dugongs within the survey area but not ‘available’, i.e., not at the surface or visible) and perception bias (dugongs ‘available’, but not detected by the observer).

To estimate availability bias, each dugong sighting is assigned an availability class (1–8) according to the water turbidity and Beaufort sea state at the location of the sighting, and the associated availability probability estimates provided by Pollock et al. (2006) are used to correct for the number of dugongs missed at that location due to them being ‘unavailable’.

The dugong research team from James Cook University (JCU) are developing methods to improve availability corrections, specifically by compensating for variation in availability bias as a function of bathymetry (and dugongs having variable distribution across depths). These new methods will be adopted within the analysis once they are made available to the research team (they are expected to be developed by mid-2013).

A mark-recapture multiple observer model will be used to estimate the proportion of the ‘available’ dugongs that are actually counted by the observers (Marsh and Sinclair, 1989a, Pollock et al., 2006) to account for perception bias. Dugong groups are "marked" when seen by one observer and then "recaptured" when seen by both. These data are modelled to determine whether the probability of an available dugong being detected is conditional on the observer, experience (primary or secondary observers), or side (port or starboard) using the MARK program (White and Burnham, 1999). The perception probabilities used for each observer are those provided by the model that best fit the data.




The abundance estimate is then calculated as per Pollock et al. (2006), where each sighting is corrected for the proportion of the survey area sampled, the probability of a group of dugongs being available and being detected given that it was available. Standard errors are obtained using a Monte Carlo simulation method as detailed in Pollock et al. (2006). All dugong groups containing more than ten individuals are excluded from the above analysis and added to the final population estimate (Norton-Griffiths, 1978).

2.4 Seagrass Surveys

2.4.1 Objectives

Characterise areas of seagrass within the predicted zone of moderate impact where dugongs were sighted.

Where possible, identify dugong feeding trails within seagrass patches to help infer areas of habitat use.

2.4.2 Overview

This component of the project will use dugong sightings (from aerial surveys and or satellite tagging) to target locations of possible seagrass habitat for characterisation and spatial delineation using a towed or dropdown camera. The study will provide information on habitat use and possible spatial variation in seagrass patches.

2.4.3 Survey Methods

The locations of sightings from aerial surveys, and locations where satellite tagged dugongs spend the majority of their time will be considered indicative feeding areas in the Project area within the predicted zone of moderate impact (as identified in the final Environmental Impact Statement). These sites will be surveyed from a boat using a remotely operated towed video system consisting of a high definition video/stills camera with two light emitting diode arrays attached to an adjustable frame. Commonwealth Condition # 37b defines the survey by specifying that the seagrass surveys be conducted “within the predicted zone of moderate impact as identified in the final Environmental Impact Statement”.

The frame will be deployed off the stern of the vessel using an A-frame and towed at a speed of approximately 1–1.5 knots and maintained at a target depth approximately 1 m above the seabed. The vessel will follow a parallel transect survey designed to characterise habitats and map the spatial extents of the local seagrass patches. Transect width can be depth dependent and may vary between sites.

The video feed from the towed camera will be displayed in real time with an overlay showing the vessel position, transect identification and time stamp. Video footage will be recorded on the surface on a hard disk drive within the towed video console. Digital still images will be captured frequently (approximately every five seconds) by an observer on the surface and recorded on the video camera internal hard drive. All images and video footage will be backed up daily during the survey onto independent external hard disk drives.

The live towed video feed to the surface will be used to undertake geo-referenced qualitative classification of benthic habitats types and substrates. Footage will be reviewed in real time by marine scientists onboard the vessel with observed habitat and substrate classified at approximately 30 m intervals along each transect.

The seagrass survey will be conducted once during Phase 1, following the July aerial survey, which will supply the dugong sighting data. The need for, and design of, surveys in Phase 2 and 3 will be discussed in consultation with the DTAP.




Data analysis

A quality control process will be used to ensure that only still images of suitable quality will be used for point analysis using Coral Point Count with Excel extensions (CPCe) 3.5. Images will be excluded from the analysis if any of the following are observed:

Image was too far from the seabed

High turbidity obscured the image of the seabed

Motion blur.

After the quality control process is complete, approximately 30 randomly selected images for each transect will be used to estimate the percent cover of benthic habitats using CPCe.

2.5 Satellite Tagging

2.5.1 Objectives

Conduct a preliminary satellite tracking study of dugongs to identify movement behaviours in the immediate Project area during Phase 1 of the project.

Assess feasibility of broader regional study of satellite tracking of dugongs.

Subject to the success of the satellite tracking study, additional tagging events may occur to determine whether dugong movements and habitat use are altered during and post construction periods.

2.5.2 Overview

Detailed information about individual dugong habitat use can be obtained from satellite tracking (Marsh and Rathbun, 1990, Holley, 2006, Sheppard et al., 2006, Sheppard et al., 2009, Sheppard, 2008, Sheppard et al., 2010, Cambell et al., 2010). In Western Australia satellite tags have previously been deployed on dugongs in Shark Bay and the Western Kimberley region. There are no data on dugong habitat use and movements around the Exmouth Gulf/ Ningaloo Reef/ Pilbara region. Chevron Australia has been advised that GPS satellite tags and time depth recorders be deployed on dugongs in the identified areas of high dugong density in proximity to the Project footprint area. The satellite tags will provide information about dugong movements and habitat use within the area and may also identify broad, regional-scale movements.

Identification of dugong density will come from the associated aerial surveys. The first year of tagging will be considered a pilot project as catching animals will be contingent on there being a suitable abundance and density of animals, and suitable conditions for catching dugongs in the identified timeframe. The decision to reject tagging dugongs in the Project area in favour of Exmouth Gulf, or an alternative suitable area, in Phase 1 will be based on advice of Murdoch University/Customised Animal Tagging Solutions and the seagrass/dugong expert assigned to the DTAP. The survey team will spend 20 days in the field attempting to tag dugongs, including days spent in an alternate area, if required. If tagging is completed before the 20 day period, the team will demobilise.

The satellite tags will provide information about dugong movements and habitat use within the area and may also identify broad, regional-scale movements. Movement distances, travel speeds, home ranges and diving behaviour will be estimated for each individual and compared between dugongs. Results from all analyses will be plotted in ArcView Geographic Information System (GIS) to display spatial and temporal distribution patterns among dugongs.




The success of satellite tagging, will be reviewed by Chevron Australia following the completion of each survey. If satellite tagging is providing effective data on dugong movements and behaviour, in response to construction activities at the site, then the program will be continued for an additional survey. Effective data is defined for the purposes of this Plan as data which is sufficient to inform adaptive management and manage potential impacts to dugong’s and their feeding habitat in accordance with EPBC 2008/4469 Condition 37.

If satellite tagging is not considered to be effective, then Chevron Australia will consult with DOTE and the independent dugong/seagrass expert selected for DTAP to seek endorsement to discontinue the satellite tagging program in subsequent phases. In the event that satellite tagging is discontinued a ‘lessons learned’ document will be prepared for submission to DTAP and DOTE. This document will discuss how satellite tagging may be used (or otherwise) to inform adaptive management and manage potential impacts associated with dredging. As well as assessing the techniques and equipment used for dugong satellite tagging by the DRP in comparison with other dugong tagging methods. This document will be prepared within 12 months from approval to discontinue to the tagging program.

2.5.3 Tagging Methods

The study will use tags capable of recording information on locations and travel paths in a variety of bathymetric profiles throughout this region, as well as fine scale movements within preferred habitat, and movements following tidal flows. Where practicable, dugongs will be captured using standard catch protocols as used in existing studies and approved through associated ethics committees. Ethics approval will be sought by Murdoch University. Suitable dugongs (adults without an attendant calf) will be located during high tide when the animals move up into intertidal waters. A catch boat will then herd the animal into the shallows whereupon a field assistant will jump from the side of the boat onto the tail of the dugong to prevent it from escaping. The dugong will then be supported in a flotation tube to allow it to surface and breath and secured against the side of the catch boat. The tag will be attached to the tail of the dugong via a harness that is wrapped around the caudal peduncle in a padded strap. The tags will be capable of measuring the animal’s dive profile during the tracking period. Dive data will be analysed using protocols previously developed (Hagihara et al., 2011).

The sex, length and girth of the dugong will be recorded and a DNA sample taken before it is released, where practicable. With an experienced team the dugong capture, tagging and release process takes less than 15 minutes.

Tag units will be located in the field from either boat or radio tracking equipped aircraft via triangulation of a VHF-signal, as far as practicable, to recover detached tags. Each tag will have a weak link that can be broken by the animal if it becomes entangled in marine obstructions such as coral or mangroves. Also incorporated into the harness assembly attaching the tag to each animal is a backup corroding link comprised of a zinc bolt in a stainless steel shackle. The bolt will slowly corrode in a galvanic reaction in seawater and release the harness in about three months, depending on the water temperature. The proposed tagging study will need to consider the ethics of capturing dugongs, as well as the health and safety of those people participating in this activity before implementation.

2.5.4 Data Analysis and Movement Determination

Dive data will be obtained via remote satellite link and/or by downloading directly from recovered tags. The GPS data will be processed using dedicated software so that accurate locations can be calculated. Spatial data will be analysed to define Home Range (Kernel 90 and 50% contours with least squares cross validation smoothing function), travel distances




and speeds (Sheppard et al., 2006, Holley, 2006). Determination of Home Ranges will allow for the identification of locations for assessment of habitat structure. Additional existing raster datasets of bathymetry and sea surface temperature will be incorporated as base layers into analyses as well as tidal movement to provide a generalised picture of individual movements in relation to abiotic forcing factors. Data on dive patterns will, as far as practicable, be analysed using protocols developed by Hagihara et al. (2011).

2.6 Spatially Explicit Population Modelling

2.6.1 Objectives

Use data from aerial surveys conducted during this research, as well as previous surveys of Exmouth Gulf and the Pilbara region, to develop spatially explicit models of dugong distribution and relative density throughout our survey area (Exmouth Gulf to Barrow Island).

Use the models to determine areas of relatively high conservation significance for dugongs within the survey area.

2.6.2 Overview

Grech et al. (2011) advise that insufficient knowledge exists of dugong habitat requirements to undertake dugong habitat suitability modelling, and that dugong density spatial modelling provides a robust surrogate for predicting important habitat areas. Dugong aerial surveys along the entire Queensland coastline, through to the Torres Strait and the Gulf of Carpentaria, have been used to develop spatially explicit population models (Grech et al., 2011, Grech and Marsh, 2008, Grech and Marsh, 2007). These models predict the broadscale patterns of dugong distribution and assist in identifying the relative significance of habitat areas for dugong conservation.

Chevron Australia has been advised to develop a spatially-explicit dugong population model using data from the aerial surveys conducted during Phase 1, and that this model be updated yearly following each survey. Previous data from four surveys in Exmouth Gulf (Hodgson et al., 2008) and one survey of the Pilbara region (Prince et al., 2001) will be used to further inform this model. The model will allow us to determine the areas of highest conservation value to dugongs, and may show whether these areas change during the three Phases of the Project.

2.6.3 Data analysis

The model will be developed using relative dugong densities throughout the survey as described in Grech et al. (2011). The scale of the planning units used to interpolate the data will depend on the dugong sighting numbers, as will the classification categories for dugong densities throughout the survey area. Depending on the amount of data collected at each Phase, the researchers will produce a model for each Phase of the Project, and/or separate models according to seasons. If too few data are available, the model outputs will be inconclusive or misleading. Consequently, the decision when to run the model will be based on expert advice from the lead scientist and study modellers.

2.7 Passive Acoustics

Passive acoustic techniques are increasingly used to monitor many species of mammal. However, it is our professional opinion that these methods will not provide reliable data on dugong abundance or distribution. Passive acoustics relies on the pre-determined relationship between a species’ vocal exchanges and their behaviour to estimate abundance. Although preliminary studies have been conducted (Anderson and Barclay, 1995, Niezrecki, 2003, Shiraki et al., 2009, Tsutsumi et al., 2006), the use of passive




acoustics to monitor Sirenia remains in its infancy, requiring further development to confirm vocalisation rates and contexts, streamline data acquisition and develop data processing techniques. The source levels of dugong calls are unknown, however, preliminary recordings have suggested that in very shallow water (<3 m) the propagation of dugong calls limit their detection range. The estimated low density of the dugong population around the Wheatstone site, and the possible limits in detection range of a vocal dugong, suggested that this method of monitoring was unlikely to provide useful data, and therefore, is not proposed here.

2.8 Salvage and Necropsy of Dead Dugongs (Dugong dugon)

2.8.1 Background

During a conference call held on 4 August 2011, staff members from the Department of the Environment (DOTE) (formerly Department of Sustainability, Environment, Water, Population and Communities) encouraged Chevron Australia to develop and adopt procedures to salvage dead dugongs, in the Project Area, to determine causes of mortality. Further, Condition 37e requested consideration is given to include “Methodology for opportunistic research via dugong salvage and necropsy” in the DRP. Note that Chevron Australia had originally proposed including these Guidelines in the Conservation Significant Marine Fauna Interaction Management Plan, but based on Condition 37 this will now be addressed in this DRP.

2.8.2 Dugong Salvage and Necropsy Guidelines

In the event that dugong salvage and necropsy (post-mortem) is required during the Wheatstone construction phase, the approach used will be based on procedures recommended by Eros et al. (2007) in the manual Procedures for the Salvage and Necropsy of the Dugong (Dugong dugon). This manual is published by the Great Barrier Reef Marine Park Authority and is available electronically (see link below). Due to the size of this manual (98 pages) it has not been reproduced in this DRP.

2.8.3 Implementation of Guidelines

The requirement and need to implement these guidelines, or to adapt them when appropriate, will be taken on advice from the DTAP.

2.9 Determining Impacts: Data analysis and limitations

Four (4) aerial surveys were conducted during Phase 1 (pre dredging), two (2) surveys will be conducted for each year of Phase 2 (during dredging) and two (2) surveys will be conducted in Phase 3 (post dredging). The survey area covers the site where impacts of dredging are predicted (Impact Site) and extends north (to Barrow Island) and south (to Exmouth Gulf). Based on the most current information (e.g. plume model outputs) the survey areas south of Barrow Island and Exmouth Gulf are considered appropriate reference areas. The latter two areas have previously had relatively high dugong densities, and will be considered as potential Reference Sites. (Reference sites are assumed to be affected by the same natural influences as the impact site and have no anthropogenic influences. However, there may be difficulties here as they may be suffering anthropogenic impacts as well). In order to investigate whether dredging activities during the Project have influenced the distribution and densities of dugongs in the Onslow area, the researchers will analyse the data using one, or a combination of, the following techniques:

1. Basic time series analysis – investigating the changes in dugong numbers over time throughout the survey area and considering each site separately. This has the advantage of not requiring any assumption of the two non-impacted sites being reference sites. However, under this approach, impact and natural changes are confounded.




2. Before-After/Control-Impact (BACI) – if it can be assumed that the two sites are Reference sites, a formal BACI analysis will be conducted. This has the advantage of allowing us to separate natural temporal changes from impact changes.

3. Gradient analysis – If there is a large enough number of dugong sightings throughout the survey area, changes in dugong density will be investigated as a function of distance from impact, and time (i.e. before, during and after impact).

The level of analysis conducted will depend on the power of each analysis, which is dependent on the number of sightings. The analysis chosen will also be based on what other factors might be influencing dugong distribution and densities, and whether it can be assumed that dugongs in all three areas are being influenced by the same natural variation.

The satellite tagging data will be used to further inform the aerial survey results. Gaining an understanding of individual dugong movements and habitat use within the area, and a qualitative assessment of how these have changed throughout the three Phases of the Wheatstone Project, will provide invaluable insight into why changes have occurred in the dugongs’ broad scale distribution. The dive data obtained will, if possible, also provide further data to a current Australian Marine Mammal Centre funded project entitled: ‘Improving the accuracy of dugong aerial surveys by better correcting for availability bias’, where dive data is being used to determine whether time of day and water depth affect the proportion of time dugongs are within the visible portion of the water column.

2.9.1 Limitations

Our knowledge of the natural variation in dugong distribution and abundance within the study area is limited by very little prior data on dugongs in the area, and the fact that Phase 1 will consist of one year of data collection, so therefore the study will not have data on inter-year variation. This does not apply to Exmouth Gulf (data exist from four previous surveys), and there are data from the Pilbara region (Prince et al., 2001), however the latter survey was conducted over ten years ago. It is also recognised that dugong sightings were collected during a whale survey off Onslow (Jenner et al., 2010), and that there was a dugong aerial survey covering Onslow to Exmouth Gulf conducted in August 2010 (RPS, 2010). However, neither survey is directly comparable to the surveys proposed in terms of the scale of the region to be surveyed and the seasonal variation in distribution. Dugongs undertake large-scale movements at the scale of hundreds of kilometres (Gales et al., 2004, Marsh et al., 2004, Sheppard et al., 2006). Thus changes in the dugong population estimates before and after dredging could be difficult to interpret because it is impossible to separate the effects of dugong movements into or out of the survey area from changes in the size of the dugong population per se, especially when the survey area is relatively small, or dugong numbers are relatively low.

The aerial surveys, however, are critical for providing a baseline understanding of the dugong distribution and abundance prior to industrial activities. They will allow us to determine the relative densities of dugongs throughout the area and from that, suggest the areas of significant habitat value for dugongs. The satellite tagging will allow us to understand the diurnal movements and potential links between habitat areas within the region.

2.9.2 Potential Biological Removal

Because of the difficulty in detecting population trends across surveys, Wade (1998) suggests that when human impacts are known to be affecting a marine mammal population, a better estimate of impact would be to monitor mortality rates and determine the Potential Biological Removal (PBR). The PBR is the maximum level of human-caused mortality that can occur in a population from all causes (e.g. accidental entanglement in fishing nets or




vessel strikes), while allowing the population to reach or maintain an optimal sustainable size, and is the product of a minimum population estimate (which can be obtained from aerial surveys), half the maximum rate of increase, and a recovery factor that allows for population growth and compensates for uncertainties in population estimates or responses to human impacts (Wade, 1998). In the USA, monitoring anthropogenic mortalities rather than population trends is considered a more robust alternative for assessing the need for management action to protect marine mammal stocks, provided the required statistics are known or inferred with some confidence (Read and Wade, 2000). Marsh et al. (2004) used this approach to assess the sustainability of the Torres Straight dugong fishery. They note that defining a recovery factor is somewhat subjective and should be conservative for a threatened species that can be affected by stochastic events like floods and cyclones. A conservative estimate of the recovery factor can account for uncertainty in population estimates.

As part of the assessment of potential impacts of the Wheatstone development on dugongs the researchers will use the aerial survey estimates to develop an estimated PBR, which can then be compared to mortality data obtained through the salvage and necropsy program. It is recognised that there are a number of uncertainties incorporated with the PBR estimate; however this technique provides some understanding of whether mortality levels are likely to be sustainable, and should be considered an additional tool for understanding the impacts of the Wheatstone project.

2.9.3 Project Management, Statistical Advice and Project Personnel

All research proposed in this document will be overseen by a Project Coordinator, whose role is to ensure that all work is conducted with satisfactory rigor, by the appropriate personnel, within the agreed timeframes. All reporting and communications will be coordinated through this person. It is proposed that Dr Hodgson take this role.

Prof. Ken Pollock will be providing statistical advice, particularly in relation to analysing unmanned aerial survey data, and detecting impacts of dredging on dugongs using all types of data. Individuals are mentioned in the DRP to undertake specific tasks. These individuals have agreed to participate. However, if an individual is unable to participate, Chevron Australia will work with the research team to find an appropriate replacement.

2.9.4 Peer Review

The results of the project will be peer-reviewed at the end of each Phase in order to evaluate the approaches described in this DRP and to allow it to be modified for each successive Phase in a process of adaptive research. This review will be led by the independent seagrass/dugong expert selected for the DTAP and in consultation with Chevron Australia and the researchers involved in the studies. Recommendations by the independent expert, and responses to these recommendations, will be provided to DOTE as part of the complete report for Phase 1.

2.9.5 Deliverables and Schedule

The research teams will provide milestone reports to Chevron Australia associated with their respective studies:

Aerial surveys

Tagging study

Population modelling

Seagrass survey.




The dates for submitting the reports will be finalised once the schedule is determined (see below).

As stated in Section 2.3.3, the timing of the aerial surveys will take into consideration historical weather data and tidal information. The aerial surveys will be scheduled with an effort to survey during the widest range of historical rainfall levels, i.e., the survey will start immediately before the wet season, during the wet, immediately before the dry season and during the dry. But the researchers will also consider likely conditions that will affect the logistics of conducting the surveys, so that the dates chosen will avoid high winds and spring tides.

The timing of the satellite tagging will also take into account the seasonal climate data as well as the likelihood of dugongs being found in the area. According to the apparent seasonality in dugong numbers (see Jenner et al., 2010) the researchers will need to conduct the tagging no later than the end of August. It should be noted that the first satellite tagging trip will require at least three months of preparation in order to obtain tags and the necessary permits.

The following is an indicative schedule for Phase 1. Note that the start date of dredging has not been fixed and therefore the final schedule will be influenced by this date:

Date Task

March 2012 Finalise DRP

May 2012 First aerial survey

July 2012 Second aerial survey (third and fourth surveys to be determined¹); seagrass survey²

August 2012 Tagging study³

February 2013 Final reporting and review for Phase 14

¹The aim is to have surveys spaced approximately three to four months apart where practicable. The commencement of dredging will influence the dates in this schedule. Precise dates for the commencement of each survey will be influenced by tidal and climatic factors (see text in DRP for justification).

²Indicative survey date only. The survey may be in either July or August.

³Planned to be undertaken during or before August 2012 (see text in DRP for justification). 4Indicactive date only. Dates will be influenced based on the commencement of Phase 2.

2.9.6 Review, Approval and Revision of this Plan

Chevron Australia is committed to conducting activities in an environmentally responsible manner and aims to implement reviews of its environmental management actions as part of a programme of continuous improvement. This commitment to continuous improvement means that the Proponent will review the DRP to address matters such as the overall effectiveness, environmental performance, changes in environmental risks and changes in business conditions on an as needed basis (e.g. in response to new information).

EPBC 2008/4469 Conditions 5 and 6 requires that Chevron Australia may only implement the Project otherwise than in accordance with the provisions of this DRP which regulate the matters of National Environmental Significance relevant to this DRP from the date of approval of any variation to this DRP by the Commonwealth Minister.




2.10 References

ANDERSON, P. K. & BARCLAY, M. R. 1995. Acoustic signals of solitary dugongs: physical characteristics and behavioral correlates. Journal of Mammalogy, 76, 1226-1237.

CAMBELL, R., HOLLEY, D. & GROUP, B.-J. R. 2010. Movement behaviours and habitat usage of West Kimberley dugongs: a community based approach. Hobart: Unpublished report to Australian Marine Mammal Centre.

EROS, C., MARSH, H., BONDE, R., O'SHEA, T., BECK, C., RECCHIA, C., DOBBS, K., TURNER, M., LEMM, S., PEARS, R. & BOWATER, R. 2007. Procedures for the salvage and necropsy of the dugong (Dugong dugon) - Second Edition. Townsville: Great Barrier Reef Marine Park Authority, Research Publication No. 85.

GALES, N. J., MCCAULEY, R. D., LANYON, J. M. & HOLLEY, D. K. 2004. Change in abundance of dugongs in Shark Bay, Ningaloo and Exmouth Gulf, Western Australia: evidence for large scale migration. Wildlife Research, 31, 283-290.

GRECH, A. & MARSH, H. 2007. Prioritising areas for dugong conservation in a marine protected area using a spatially explicit population model. Applied GIS, 3, 1-14.

GRECH, A. & MARSH, H. 2008. Rapid assessment of risks to a mobile marine mammal in an ecosystem-scale marine protected area. Conservation Biology, 22, 711-720.

GRECH, A., SHEPPARD, J. & MARSH, H. 2011. Informing species conservation at multiple scales using data collected for marine mammal stock assessments. PLoS ONE, 6, e17993.

HAGIHARA, R., JONES, R. E., SHEPPARD, J. K., HODGSON, A. J. & MARSH, H. 2011. Minimizing errors in the analysis of dive recordings from shallow-diving animals. Journal of Experimental Marine Biology and Ecology, 399, 173-181.

HODGSON, A. J. 2007. The distribution, abundance and conservation of dugongs and other marine megafauna in Shark Bay Marine Park, Ningaloo Reef Marine Park and Exmouth Gulf. Denham, Western Australia: WA Department of Environment and Conservation.

HODGSON, A. J., MARSH, H., GALES, N., HOLLEY, D. K. & LAWLER, I. 2008. Dugong population trends across two decades in Shark Bay, Ningaloo Reef and Exmouth Gulf. Denham, Western Australia: WA Department of Environment and Conservation.

HOLLEY, D. K. 2006. Movement patterns and habitat usage of Shark Bay dugongs. Masters, Edith Cowan University.

HOLLEY, D. K., LAWLER, I. R. & GALES, N. J. 2006. Summer survey of dugong distribution and abundance in Shark Bay reveals additional key habitat area. Wildlife Research, 33, 243-250.

HOOGE, P. N. & EICHENLAUB, W. M. 1997. Animal movement extension to ArcView. AncE: Alaska Biological Science Centre, US Geological Survey.

JENNER, K. C. S., JENNER, M. N. M. & MCCAULEY, R. D. 2010. A description of megafauna distribution and abundance in the SW Pilbara using aerial and acoustic surveys - Final Report. Perth, Western Australia: Unpublished report for URS Pty Ltd.




MARSH, H., LAWLER, I. R., KWAN, D., DELEAN, S., POLLOCK, K. & ALLDREDGE, M. 2004. Aerial surveys and the potential biological removal techniques indicate that the Torres Strait dugong fishery is unsustainable. Animal Conservation, 7, 435-443.

MARSH, H. & RATHBUN, G. B. 1990. Development and application of conventional and satellite radio tracking techniques for studying dugong movements and habitat use. Australian Wildlife Research, 17, 83-100.

MARSH, H. & SINCLAIR, D. F. 1989a. Correcting for visibility bias in strip transect aerial surveys of aquatic fauna. Journal of Wildlife Management, 53, 1017-1024.

MARSH, H. & SINCLAIR, D. F. 1989b. An experimental evaluation of dugong and sea turtle aerial survey techniques. Australian Wildlife Research, 16, 639-650.

NIEZRECKI, C. 2003. Acoustic detection of manatee vocalizations. The Journal of the Acoustical Society of America, 114, 1640.

NORTON-GRIFFITHS, M. 1978. Counting Animals. Handbook No 1, Kenya, Serengeti Biological Monitoring Programme, African Wildlife Leadership Foundation.

POLLOCK, K., MARSH, H., LAWLER, I. R. & ALDREDGE, M. W. 2006. Estimating animal abundance in heterogeneous environments: an application to aerial surveys for dugongs. Journal of Wildlife Management, 70, 255-262.

PRINCE, R. I. T., LAWLER, I. R. & MARSH, H. 2001. The distribution and abundance of dugongs and other megavertebrates in Western Australian coastal waters extending seaward to the 20 metre isobath between North West Cape and the De Grey River Mouth, Exmouth, Western Australia, April 2000. Canberra: Report for Environment Australia.

READ, A. J. & WADE, P. R. 2000. Status of marine mammals in the United States. Conservation Biology, 14, 929-940.

RPS 2010. Dugong aerial survey report: Wheatstone project. Perth, Western Australia: Unpublsihed report prepared for Chevron Australia by RPS Group.

SHEPPARD, J., JONES, R., MARSH, H. & LAWLER, I. 2009. Effects of Tidal and Diel Cycles on Dugong Habitat Use. Journal of Wildlife Management, 73, 45.

SHEPPARD, J. K. 2008. The foraging ecology of dugongs: implications for management. PhD PhD, James Cook University.

SHEPPARD, J. K., MARSH, H., JONES, R. E. & LAWLER, I. R. 2010. Dugong habitat use in relation to seagrass nutrients, tides, and diel cycles. Marine Mammal Science, 26, 855-879.

SHEPPARD, J. K., PREEN, A. R., MARSH, H., LAWLER, I. R., WHITING, S. D. & JONES, R. E. 2006. Movement heterogeneity of dugongs, Dugong dugon (Muller) over large spatial scales. Journal of Experimental Marine Biology and Ecology, 334, 64-83.

SHIRAKI, R., ICHIKAWA, K., SHINKE, T., ARAI, N., AKAMATSU, T., HARA, T. & ADULYANUKOSOL, K. Year. Development of detection device for dugong calls. In: Proceedings of the 4th International Symposium on SEASTAR2000 and Asian Bio-logging Science (The 8th SEASTAR2000 workshop), 2009. 4.




TSUTSUMI, C., ICHIKAWA, K., ARAI, N., AKAMATSU, T., SHINKE, T., HARA, T. & ADULYANUKOSOL, K. 2006. Feeding behavior of wild dugongs monitored by a passive acoustical method. The Journal of the Acoustical Society of America, 120, 1356-1360.

WADE, P. R. 1998. Calculating limits to the allowable human-caused mortality of cetaceans and pinnipeds. Marine Mammal Science, 14, 1-37.

WHITE, G. & BURNHAM, K. P. 1999. Program MARK: survival estimation from populations of marked animals. Bird Study, 46, 120-139.

Documents

Wheatstone Project - Chevron Corporation · 2018. 3. 1. · Chevron Australia (See Condition 39 regarding Chevron Australia’s response). Prof. Marsh has also endorsed by letter,