The Context - IEObased fishery management is the lack of sufficient data concerning the structure and dynamics of its different compartments, both biotic and abiotic. To solve this

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Towards the understanding of the influence of the

environmental conditions on the demersal resources and

ecosystems in the western Mediterranean: Motivations,

aims and methods of the IDEADOS project

Enric Massutí

Pilar Olivar

Sebastià Monserrat

Lucia Rueda

Pere Oliver

Wrapping up of the IDEADOS project; 14-17 November 2012

BACKGROUND

• Environmental abiotic (climate and

hydrography) and biotic (preys and

predators) factors cause intra- and

inter-annual oscillations in population

dynamics of exploited species.

• Strategy for the study, exploitation and

conservation of marine living resources

must consider the complexity and

global functioning of ecosystems, their

natural variations and the factors that

control these changes.

The Context

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BACKGROUND

• In the western Mediterranean,

important fluctuations have been

described in the distribution,

structure and population dynamics

of main nekto-benthic species,

which affect their accessibility to

fishing exploitation (Caddy, 1993).

• There is a general agreement that

such fluctuations are partly due to

abiotic and biotic factors.

The Context

BACKGROUND

Spatio-temporal variability in the

oceanographic conditions, as well as

intra- and inter-annual fluctuations

in nekto-benthic species, have also

been reported in the Balearic

Islands, affecting species subjected

to fishing exploitation, both fish and

cephalopods from the shelf (Oliver,

1993; Quetglas et al., 1998) and

crustacean decapods from the slope

(Carbonell et al., 1998).

The Context

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BACKGROUND

One of the major obstacles for the

implementation of the ecosystem-

based fishery management is the

lack of sufficient data concerning

the structure and dynamics of its

different compartments, both biotic

and abiotic. To solve this problem, a

multidisciplinary approach is

needed (Cury, 2006).

The Context

BACKGROUND

The former IDEA project

Influence of oceanographic structure and dynamics on

DEmersal populations in waters of the BAlearic Islands

www.ba.ieo.es/idea

Between 2003 and 2006, we studied:

� Seasonal changes in environment

(hydrography, substrate and trophic

resources) and its influence on

exploited demersal populations.

� How inter-annual variability of abiotic

factors could impact on the population

dynamics of these species.

It was the first attempt towards understanding dynamics of

exploited demersal ecosystems off Balearic Islands

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BACKGROUND


Aristeus antennatusMerluccius merluccius

Two approaches:

� Intra-annual: Six seasonal surveys and the monitoring of the

bottom trawl fishery.

� Inter-annual: Analysis of population parameters of these

species and climatic, meteorological and oceanographic

indices, as indicators of environmental conditions.

STUDY AREA

The Balearic Islands: geomorphology

• Separated from the Iberian Peninsula

by 95 nm and 800-1800 m depth

• Shelf narrow and steep in N (3 km

width) and wider in S (up to 35 km)

• Slope gentle in W & S (6º inclination),

while N & E show and abrupt slope

(16º), with several seamounts and a

pronounced scarp to >2000 m depth.

Acosta et al. (2002)

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STUDY AREA

The Balearic Islands: types of bottom

• There is not river runoff.

• Shelf sediments are mainly biogenic

sands and gravels;

• sandy-muddy and detrital occur at

the shelf-slope break:

• whereas muddy bottoms of biogenic

origin dominate the deeper areas.

Canals & Ballesteros (1997)

STUDY AREA

The Balearic Islands: hydrodynamics

They delimit the Balearic and Algerian sub-basins,

characterized by different oceanographic conditions and

being connected by a series of channels, which play an

important role in the regional circulation, as passages for the

exchange of water masses.

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STUDY AREA


� Atlantic Waters (AW; 50-100 m),

with high seasonal variations of

temperature (13-26°C).

� Winter Intermediate Water (WIW;

100-300 m), originated in the Gulf

of Lions by deep convection, with

minimum temperature (~12.5ºC).

� Levantine Intermediate Water

(LIW; 200-700 m), with maximum

temperature (~13.3°C) and salinity

(~38.5) along the water column.

� The Western Mediterranean Deep

Water (WMDW) deeper.

STUDY AREA


� The Balearic sub-basin is more

influenced by atmospheric forcing

and Mediterranean waters, which

are colder and more saline.

� The Algerian sub-basin is affected

basically by density gradients

forcing and warmer and less saline

Atlantic waters (Pinot et al., 2002).

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STUDY AREA


The Northern Current (NC) flows

downwards along the slope of the

Iberian Peninsula and bifurcates at

the Ibiza Channel, one part crosses

this channel, while the other part

flows north-eastwards along the

northern slope off Balearic Islands,

forming the Balearic Current (BC).

It is expected during spring-summer after mild winter in NW

Mediterranean, but changes after cold winter (Pinot et al., 2002).

STUDY AREA


� If significant WIW is generated in

cold winters, NC can be blocked at

Ibiza Channel and re-circulates

cyclonically, reinforcing BC.

� Inter-annual variability in the

regional circulation is related to

amount of WIW reaching the

channels during spring.

Millot (1999); Pinot et al. (2002)

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STUDY AREA

The Balearic Islands: productivity

Within the general oligotrophy

of the Mediterranean, waters

around Balearic Islands,

where there is no nutrients

supply from river runoff, are

more oligotrophic than waters

off Iberian coast and Gulf of

Lions (Estrada, 1996).

Frontal meso-scale events between Mediterranean and Atlantic waters

(Pinot et al., 1995), and input of cold northern water into the channels

(Fernández de Puelles et al., 2004), can act as the external fertilisation

mechanisms that enhance productivity off the Balearic Islands.

STUDY AREA

The Balearic Islands: deep trophic networks

Submarine canyons off NE Iberian

Peninsula play an important role

in transference of matter from

shelf (mostly since river run-off)

to slope (Puig et al., 2000),

increasing availability of benthic

preys and widening the spectrum

of deep trophic networks (Cartes,

1998; Carrasón and Cartes, 2002).

In Balearic Islands, where these structures do not exist (Acosta et al.,

2002), organisms of the deep benthos depend more directly on

planktonic preys (Maynou and Cartes, 2000; Cartes et al., 2007).

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STUDY AREA

The Balearic Islands: deep trophic networks

� Peninsular vs. insular slopes, in

terms of crustacean and fish

communities (Maynou & Cartes,

2000; Massutí et al., 2004).

� Balearic vs. Algerian sub-basins,

in terms of trophic webs (e.g.

Cartes et al., 2001):

� More supported by plankton

than by benthic productivity

in Algerian sub-basin.

� Supra-benthos plays a more

important role in Balearic

sub-basin.

PREVIOUS RESULTS


Distinct hydrodynamic scenarios were

verified in traditional fishing grounds

northern and southern Balearic Islands

(López-Jurado et al., 2008).

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This could be on the basis of the

differences observed between both

areas with respect to:

• Trophic resources: zooplankton and

supra-benthos

Cartes et al. (2008a, 2010)

PREVIOUS RESULTS





• Nekto-benthic assemblages

Moranta et al. (2008)

PREVIOUS RESULTS

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• Hake population dynamics, biology,

condition and feeding

Hidalgo et al. (2008a, 2008b)

Cartes et al. (2009)

PREVIOUS RESULTS





• Red shrimp population dynamics,

biology, condition and feeding

Guijarro et al. (2008)

Cartes et al. (2008b)

PREVIOUS RESULTS

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• Population dynamics, biology, and

condition of other deep water

decapod crustaceans

Guijarro et al. (2009, 2012)

Parapenaeus longirostris Plesionika martia P. heterocarpus

PREVIOUS RESULTS


Models explaining how the climatic

conditions in NW Mediterranean determine

hydrodynamics around Balearic Islands

(Monserrat et al., 2008) and influence the

recruitment of hake and red shrimp

(Massutí et al., 2008) were developed.

0

25

50

75

100

0

500

1000

1500

2000

2500

3000

1980 1985 1990 1995 2000 2005

SS

B (to

ns)R (n

x100

0)

Years

R SSB

PREVIOUS RESULTS

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Environmental factors, modelled by meso-

and macro-scale climatic indexes, and/or

biological factors (spawning population and

body condition), influence dynamics of hake

and red shrimp and their accessibility to

fishing exploitation (Carbonell et al., 2008;

Massutí et al., 2008).

1940 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005

CP

UE

(K

g/H

P)

0

10

20

30

40

50

CPUE

PREVIOUS RESULTS


� Phase transitions, induced by

long term fishery harvesting,

were shown with respect to

hake abundance and length-at-

age (Hidalgo et al., 2009).

� Synergistic effects of fishing,

climate and hake internal

dynamics (Hidalgo et al., 2011).

PREVIOUS RESULTS

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From stable isotopes analysis in hake otoliths,

Hidalgo et al. (2008b) raised the hypothesis

that reinforcement of slope fronts system in

NW Mediterranean could favour connectivity

between Iberian coast and Balearic Islands.

These conditions could increase arrival to

insular bottoms of primary stages of hake,

from spawning made on peninsular slope.

PREVIOUS RESULTS

The former MAS project

“Analysis of the spatial structure of early life

stages of hake, anchovy and sardine in the

northwestern Mediterranean. Interaction with

hydrography and trophic availability”

� Preferential location of hake eggs and

larvae on the continental shelf margin

� Oceanographic meso-scale phenomena,

associated with shelf-slope currents,

determine their distribution

Olivar et al. (2010)

PREVIOUS RESULTS

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The current IDEADOS project

The project “Structure and dynamics of the bentho-pelagic slope

ecosystem in two oligotrophic zones of the western Mediterranean: a

multidisciplinary approach at different spatio-temporal scales in the

Balearic Islands” (2009-2012) was based on the assumptions:

� In Balearic Islands, the coupling pelagic-benthic domains is more

important than off Iberian Peninsula, in which continental

contributions act as drivers of productivity in deep ecosystems.

� The slope northern Archipelago, which receives great influence from

continental margin, should have more availability of benthic preys

than Algerian sub-basin, where pelagic system should play a relevant

role as trophic resources for deep benthic communities.

HYPOTHESIS & OBJECTIVES


The hypothesis of IDEADOS project

� Differences observed between nekto-benthic communities of

both sub-basins could be due to different trophic structure,

associated with the different degree of oligotrophy.

� Population dynamics and accessibility to fishing exploitation for

some deep sea key species (e.g. hake and red shrimp) can be a

good example.

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The aims of IDEADOS project

The overall objective is to determine relationships between

environmental conditions and nekto-benthic slope communities

in two areas of the western Mediterranean, with distinct

geomorphologic and hydrodynamic characteristics.

� Different temporal scales (year, season, monthly, fortnightly,

day) and organization levels (population, community and

ecosystem) have been also analyzed.

� Special emphasis on the study of:

� trophic coupling between deep nekto-benthic and meso-

pelagic species, within the context of the hydrodynamics;

� and on hake and red shrimp.



1. To determine the effect that seasonal variability of the

hydrodynamics has on the species and communities of the

slope and on their trophic resources along the water column,

by means of the study of the various compartments of the

zooplankton (micro-, meso- and macro-zooplankton) and

nekton (micro- and macro-nekton).

2. To determine the viability of applying acoustic methods for the

characterization of the communities in the Deep Scattering

Layers (DSL) of the meso-pelagic domain.

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3. To determine the influence of the high frequency variability

(daily, fortnightly and/or monthly) of the oceanographic

conditions on the biology and dynamics of the red shrimp.

4. To contextualize the oligotrophic ecosystems of the Balearic

Islands from a global perspective, including adjacent areas of

western Mediterranean, from: (i) the estimation of the degree

of connectivity between populations of the continental margin

of the north-western Mediterranean and the Balearic Islands,

using geochemical markers in hake otoliths; and, (ii) the

analysis of information from fishing exploitation on the

peninsular coast and the archipelago.

STUDY STRATEGY & SAMPLING

The approaches of IDEADOS project

• Collection of data and samples

• Fishing exploitation monitoring

• Compilation of information from

other databases (e.g. satellite

images, surveys and research

projects) and published works

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Collection of data and samples at sea




Traditional fishing grounds

Vessel Monitoring System

Sóller

Cabrera

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Sóller

Cabrera

� More irregular slope, gentle in W down to 1100 m

and very pronounced scarp down to 2600 m in E.

� Less defined hydrodynamic, under influence of

gyres from Atlantic waters.

� Gentle slope reaching 1800 m and linking with

peninsular margin.

� Hydrodynamic determined by intra- and inter-

annual variability in the slope fronts system.

~50 nm




DEMERSAL RESOURCES

FISHING EXPLOITATION

HYDROLOGY PRODUCTIVITY

MOORINGS

PARTICLES FLUX

HYDRODYNAMICS

FISHERY MONITORING

RE

MO

TE

SE

NS

ING

DEMERSAL RESOURCES - ENVIRONMENT

It was very costly to increase sampling intensity applied during IDEA

project (6 surveys along one year!). A very high temporal resolution was

only possible by mooring instruments and monitoring of the fishing fleet.

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Sampling at sea

Moorings

� Nov’09 – Feb’11

� Revisions: March’10 and Sep’10

� Equipment:

� 4 CTD: 300, 500, 700 and 850 m

� 2 current meters: 500 and 850 m

� sediment trap at 30 m above bottom

� Sampling periodicity:

� Temperature and salinity: 10’

� Currents: 30’ min

� Particulate matter: 20 days


Fisheries monitoring

Bottom trawl fleet

� Daily sales bills

� Period: 2000-2011

� Harbours: Palma, Andratx & Sóller

� Landings of al species captures

� Effort (fishing trips)

� Target species: red shrimp

� Three size categories

� CPUE

� Historical series of landings

� Period: Since 1964

� All harbours of Mallorca

� All species or commercial category

Sóller

Cabrera

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Sampling at sea

Seasonal surveys

� December 2009 (late autumn)

� Destabilisation and mixture in water column, low temperatures

and high levels of production in photic layer

� Main reproductive period of hake (autumn-winter)

� Red shrimp recruitment (autumn-winter)

� July 2010 (summer)

� Strong stratification in water column, high temperatures and

low production in surface layers

� Red shrimp spawning

R/V Sarmiento de Gamboa

F/V Punta des Vent


Seasonal surveys

RE

MO

TE

SE

NS

ING

NEKTOBENTHIC COMMUNITY

MEGAFAUNA NETOPTICS

MESOPELAGIC

ECOSYSTEMNEKTON NETS

ACOUSTICS

SEDIMENT ANALYSIS

EPIBENTHIC COMMUNITY AND SUBSTRATE

ACOUSTICS

MULTIDISCIPLINARY SURVEYS

HY

DR

OD

YN

AM

ICS

HYDROLOGY PRODUCTIVITY

DEMERSAL ECOSYSTEMS -ENVIRONMENT

ZOOPLANKTON NETS

KEY-SPECIES TROPHISM DAILY MOVEMENTS

KEY-SPECIES TROPHISM

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Seasonal surveys

SBE-911 CTD

• Salinity

• Potential temperature

• Potential density

• Oxygen

• Turbidity

• Fluorescence

• PAR

Hydrographic data

30 stations, distributed in 5

transects, in each study area


Seasonal surveys

Zooplankton sampling

• Two stations at 200 and 900 m

• Sampling cycles of 24-48 hours

• Vertical hauls along the first

200 m of water column

• Calvet and WP2 for biomass:

• Micro-zooplankton (53 µm

mesh size)

• Meso-zooplankton (200 µm

mesh size)

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Seasonal surveys




• Depth-stratified sampling of

meso-zooplankton (333 µm),

from 500 m to surface:

• Multi-net (5 samples/haul)

• MOCNESS (8 samples/haul)


Seasonal surveys




Pro

fun

did

ad

(m)

0-30 m

30-6060-113

113-150150-200

200-400

400-600

600-850 m

200 m

900 m

MULTINET / MOCNESS

0.3 mm mesh size

24


Seasonal surveys

Deep Scattering Layers (DSL)

ACOUSTICS GROUPS

• Myctophids

• Krill

• Decapods

• Squids

• Jellyfish

• Cyclothone

• …

SIMRAD EK-60 at 18, 38, 70, 120 and 200 kHz

The use of this methodology is an innovative aspect in the

study of the deep water ecosystems in the Mediterranean.


Seasonal surveys



Sampling of micro- and macro-

nekton at DSL were made with

big pelagic trawl (10 mm mesh

size) to interpret echograms.



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Seasonal surveys



Additional sampling of macro-

zooplankton and micro-nekton

with Isaak-Kidd Mid-water

Trawl and Rectangular Mid-

water Trawl (3 mm mesh size)

and one of the nets of

MOCNESS (1.5 mm mesh size).




Seasonal surveys



The strongest and widest

acoustic sound layers, mainly

located at 400-600 m (day and

night) and near surface during

the night, were sampled.



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Seasonal surveys

Benthic sampling

• 3 stations at 250, 650 and 850 m

• 3 samples per station

• Daylight hours

Nekton-benthic species:

• Commercial bottom trawl

• Size: ~25 and 2.1 m

• Mesh size cod-end: 20 mm


Seasonal surveys

Benthic sampling

Epi-benthic species:

• Beam trawl

• Size: 3.5 and 0.6 m

• Mesh size cod-end: 10 mm



• Daylight hours

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Seasonal surveys

Benthic sampling



• Daylight hours

Supra-benthic species:

• Net attached to beam trawl

• Size: 1.25 and 0.3 m

• Mesh size: 500 µm – 1 mm


Sampling at sea

Seasonal surveys

R/V Sarmiento de Gamboa

F/V Punta des Vent

Sampling Dec’09 Jul’10 Total

CTD 51 67 118

Calvet 15 23 38

WP2 26 40 66

Multi-net 17 -- 17

MOCNESS -- 33 33

IKMT 21 46 67

RMT 20 -- 20

Pelagic trawl 15 20 35

Bottom trawl 16 18 34

Beam trawl 12 18 30

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IDEADOS Results?

• 17 IDEADOS communications:

• Hydrodynamics , dissolved oxygen & organic matter fluxes

• Zooplankton, decapod crustacean & fish larvae

• Acoustics

• Otoliths

• Pelagic crustacean & cephalopods

• Epi-benthic & demersal communities

• Feeding & food webs

• CPUEs & hydrodynamicas & climate

• Ecosistem modelling

Wrapping up of the IDEADOS project; 14-17 November 2012

Documents

The Context - IEObased fishery management is the lack of sufficient data concerning the structure and dynamics of its different compartments, both biotic and abiotic. To solve this