Pacific wide observation system to monitor biological changes of the pelagic ecosystem Simon Nicol 1 Valerie Allain 1 Jeff Polovina 2 Shane Griffiths 3 Bob Olson 4 Jock Young 5 Jeff Dambacher 6 Marta Coll 7 Simon Hoyle 1 Tim Lawson 1 Johann Bell 1 John Hampton 1 Jesus Jurado Molina 1 Karine Briand 1 Paul Dalzell 8 1 Oceanic Fisheries Programme, Secretariat of the Pacific Community , New Caledonia 2 National Marine Fisheries Service, Hawaii , USA 3 CSIRO Marine and Atmospheric Research, Brisbane, Australia 4 Inter‐American Tropical Tuna Commission, La Jolla, USA 5 CSIRO Marine and Atmospheric Research, HOBART , Australia 6 CSIRO Mathematics, Informatics and Statistics, HOBART, Australia 7 Institut de Ciències del Mar, Barcelona, Spain 8 Western Pacific Fishery Management Council, Hawaii, USA
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Pacific wide observation system to monitor biological changes of the pelagic ecosystem
1 Oceanic Fisheries Programme, Secretariat of the Pacific Community , New Caledonia
2National Marine Fisheries Service, Hawaii , USA
3CSIRO Marine and Atmospheric Research, Brisbane, Australia
4Inter‐American Tropical Tuna Commission, La Jolla, USA
5CSIRO Marine and Atmospheric Research, HOBART , Australia
6CSIRO Mathematics, Informatics and Statistics, HOBART, Australia
7Institut de Ciències del Mar, Barcelona, Spain
8Western Pacific Fishery Management Council, Hawaii, USA
Pacific tuna fisheries are the largest in the world
They contribute to economic development, government revenue, employment and food security
Pacific tuna fisheries
Analyses on the impacts of climate change on these fisheries clearly identify that tuna distributions and abundances are likely to be altered
Robust science‐based advice for decision makers is essential to ensure the sustainability of these resources
Understanding how the combined influences of fishing, climate change and other environmental variability interact and impact ecosystems is necessary for managers to design adaptation plan
Changes in the fisheries
Lehodey et al, 2011
Projected biomass of skipjack population
Fisheries management is evolving from single‐species to an ecosystem wide perspective.
Sustainability must be measured in terms of target but also non‐target species, trophicinteractions, and ecosystem structure and function.
bottom‐up, top down, wasp‐waist driven processes
Fisheries
Ecosystem perspective
Changes in the ecosystem have been demonstrated: ‐at lower trophic level: phytoplankton ‐and intermediate trophic levels: mid‐trophic predators
Changes in the ecosystem
Lancetfish Mahimahi
Snake mackerel Escolar, walu
Sickle pomfret
Polovina et al. 2009
Le Borgne et al. 2011Griffiths
Changes in the ecosystem
Estimated changes in the mid trophic level biomass under climate change for the western Pacific ocean warmpool
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Mean proportion W (±95%CI) 1992‐1994 Dieg composition
2003‐2005 Diet composition
Jumbo squid
Auxis spp.Mesopel. fishes
Epipel. fishes
Diet compositionDiet composition
Changes in the ecosystem
Yellowfin tuna diet composition in the Eastern Pacific
Olson et al.
Ecosystem monitoring
The diversity and complexity of processes operating in oceanic ecosystems can make the detection of changes in structure and function difficult. It requires developing robust monitoring systems providing reliable information on these processes.
It is important to monitor, at appropriate spatial and temporal scales (long‐time series), the adequate parameters, including physical and biological parameters at various trophic levels (not only the target species)
SeawiFS surface chlorophyll climatology with oligotrophic gyres in black
(Polovina et al. 2008)
Dynamic Biomes
Biomes to determine the appropriate scale of monitoring
Global Ocean Observing System (GOOS) provides near real time measurements of the state of the oceans (temperature, salinity, water level...) collected from satellites, buoys, floating profilers, and ships.
Global monitoring initiatives provide information of bottom‐up processes: physical oceanography and primary production.
TAO/TRITON Moored Buoy Array , a multi‐national effort, provides data in real‐time for climate research and forecasting
Physical monitoring
Large‐scale biological monitoring systems of mid‐trophic and upper‐trophiclevels of the ecosystem are inexistent.
Zooplankton and micronekton are collected punctually during scientific cruises
Despite the valuable information brought by field work, it is expensive, scarce, at small scale and with poor coverage (spatial and temporal) with no time series
Biological monitoring
Basin scale monitoring
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Net and Acoustic depth stratified (200 m day night strata) sampling along Trans Tasman transect in June 2008
Kloser, Young et al.
Ecosystem monitoring at different levels and scales is recognized as crucial
Satellite and buoys arrays allow monitoring the physical and lower trophiclevel.
Fisheries data allow monitoring some aspects of top predators
Still there is an important information gap for mid‐trophic organisms: zooplankton, micronekton and mid‐trophic predators – it has been recognized as one key information gap needed to be filled by monitoring programs to improve the parameterization of future ecosystem models. (Le Borgne et al. 2011)
Monitoring needs
The key promising to deliver information on an unprecedented scale are the ‘fisheries observer programmes’ operated by governments with the support international organisations in the Pacific.
These programmes place trained staff on board licensed tuna fishing vessels to record a wide range of information:‐catch , ‐catch composition (including non‐target species), ‐effort and ‐biological data (length, weight, stomach samples...)
Fisheries Observer Programmes
Establishment of time series of distribution and abundance for many top predators and mid‐trophic predators
Monitoring opportunities
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Blue Shark
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Oceanic Whitetip Shark
CPUE Heat Maps
Lawson 2011
Monitor biodiversity of top and mid‐trophic predators
Monitoring opportunities
(Morato et al 2010)Expected species diversity as a function of 1 × 1 degree cells.
Monitoring opportunities
Spatial variation in sex ratio at length, YFT
Establishment of time series of length, weight, sex ratio
(Hoyle et al 2011)
Monitoring of mid‐trophic level diversity and abundance through collection of stomachs
Monitoring opportunities
A good design of stomach sampling allows monitoring the mid‐trophic level
Collection of predator stomachs by fisheries observers and subsequent analyses of their contents will provide long‐term time series data on proportions and distribution of micronekton(mainly small fish and squid) which have a major influence on tuna distribution and abundance.
Monitoring opportunities
Fisheries Observer ProgrammesThere are currently 2025 longline fishing vessels registered to operate in the Pacific Ocean
Tuna fisheries in the Pacific Ocean are undergoing a revolution in the quality and quantity of monitoring data. The RFMOs and sub‐regional tuna fisheries organisations such as the Parties from the Nauru Agreement have approved policies that will increase spatial and temporal coverage of observers
From 2011, 100% observer coverage on purse‐seine vessels is a license requirement and from 2012, 5% observed coverage will be required on all longline vessels operating in the western and central Pacific; there is already 100% observer coverage on PS in the EPO (no LL but negligible offshore)
Fisheries Observer Programmes
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Purse seine fisheryNumber of sets: 2010
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Conclusions
The Pacific‐wide network of fisheries observer programs provides an important addition to the physical oceanography monitoring system and to the fisheries catch and effort data collection.
It provides pelagic ecosystem data for the mid‐trophic levels across the Pacific.
The combination of all these monitoring systems gives us the opportunity to establish a resource of information on all trophiclevels of the ecosystem for the first time at the ocean basin scale
Two important issues to take into consideration:•Longevity: create continuous time series necessary for CC monitoring•Design the appropriate sampling plan to insure collection of the require data
There is a need for preliminary analyses to design a suitable sampling plan•Detailed ecological analyses of observer data available should be implemented to provide feedback on critical data needed for ecosystem modelling and monitoring• Analyses of the dynamic oceanographic biomes (Hobday et al. 2011) is an immediate priority to evaluate the most efficient design for future sampling regime.
