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WP3: Deepwater snapper. Towards improved stock assessments and management. Outline. Background Results achieved Project sustainability Work plan for 2015 Recommendations. Background. Deepwater snapper are an important fisheries resource in many PICTs
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WP3: Deepwater snapper Towards improved stock assessments and management
Outline Background Results achieved Project sustainability Work plan for 2015 Recommendations
Background • Deepwater snapper are an important fisheries resource in many PICTs • Declines in catches in some PICTs have raised concerns about sustainability • Lack of adequate biological and fisheries data has limited development of quantitative assessments and management plans
Background • At 2011 HoF meeting, members endorsed SPC efforts to seek funding to support a deepwater snapper project • SPC obtained funding from: • Australia, Fisheries for Food Security (2012-2015) • Vanuatu, Samoa, Tonga, and the Marshall Islands • French Pacific Fund (2011-2013) & French Development Agency (2012-2013) • New Caledonia
Deepwater snapper workshop • Deepwater snapper workshop held at SPC in July 2011 • Identify priority information and training needs • Participants from 12 PICTs • The agreed outcomes from the workshop included a work plan for SPC’s deepwater snapper activities
Work Plan There are 4 priority areas: Fisheries data collection Improving biological knowledge Fisheries assessment and management Capacity development
Catch and Effort Data • SPC’s artisanal fisheries database (TUF-ART) considered best option to manage deepwater snapper data • Standardises data collection & management • Provides consistency in how and what data are collected • Minimises development and maintenance costs • Facilitates comparisons of fisheries among countries
Data management • TUF-ART database installed in many countries (Cook Islands, Kiribati, Marshall Islands, Nauru, Niue, Samoa, Tokelau, Tonga, Tuvalu, Vanuatu) Fishing Logsheet TUF-ART Database
Port sampling programs • Established & supported development of fisheries monitoring programs in Tonga, Vanuatu, Samoa, New Caledonia & PNG • Fisheries officers trained in biological sampling • Successful ongoing data collection programs will require continued support from Fisheries Departments
Biological Sampling • Scientific cruises • Port sampling
Biological Sampling • Samples collected from >4000 fish • Samples collected include: • Otoliths – age, longevity & growth, • Gonads – sex, maturity, fecundity & spawning • Fin clips & muscle – genetics, define stocks
New Species • Identified new species – Pygmy Ruby Snapper (Etelis marshi) • Developed methods to distinguish from similar species – Ruby snapper (Etelis carbunculus) Otolith shape Black tip on tail Operculum spine Pygmy Ruby Snapper (Etelis marshi) Ruby Snapper (Etelis carbunculus)
Species Identification • Waterproof species identification cards for fishers and port samplers • Distributed to Fiji, Marshall Islands, New Caledonia, PNG, Samoa, Solomon Islands, Tonga, and Vanuatu
Deepwater Snapper Habitat • Fishers know where to catch deepwater snapper, but the full extent of their habitat is unknown • Knowledge of deepwater snapper habitat can help make informed management decisions – i.e spatial planning, development opportunities • We used fisheries and oceanographic data used to model potential distribution of deepwater snapper across WCPO
Deepwater Snapper Habitat • We produced maps of the predicted distribution of deepwater snapper across the WCPO
Main Target Species • Ruby snapper (Etelis carbunculus) • Pygmy ruby snapper (Etelis marshi) • Flame snapper (Etelis coruscans) • Crimson jobfish (Pristipomoides filamentosus)
Age estimation 1 mm 1 mm Age information needed to estimate longevity, growth rates etc. We estimate age by counting bands in sectioned otoliths
Age estimation E. coruscans E. carbunculus P. filamentosus E. marshi
Growth • Slow growth rates • Extended longevity (> 30 years)
Fisheries assessment and management • Traditional stock assessments require a long time series of reliable catch and effort data • For deepwater snapper, the cost of collecting these data is not commensurate with the economic value of most fisheries • Need an alternative approach for deepwater snapper • For other data-poor fisheries, simple indicators (e.g. % mature fish in catch) have been used • Indicators could be an appropriate method for evaluating the sustainability of deepwater snapper fisheries
Age-based indicators Length is a poor indicator of age for deepwater snapper Need to develop age-based indicators Problem ... Age estimates from counting bands in sectioned otoliths is time consuming and costly A cost effective solution ... Otolith measurements (weight, thickness etc) are good predictors of age Cheaper, easier and quicker
Otolith Measurements • Weight • Length • We measured otoliths from 4 species • Simple and rapid procedure • Width • Thickness
Age Composition Number of fish Number of fish Age (years) Age (years)
Age Composition • Otolith measurements can be used to obtain age compositions of deepwater snapper • Measuring otoliths is cheaper, easier and quicker than sectioning otoliths • $10,000 to section and read 500 otoliths • $100 to measure 500 otoliths • Fisheries officers have been trained in removing otoliths • Otolith sampling programs ongoing in Tonga and Vanuatu • Age compositions provide valuable information about the stock
Age-based Indicators - Mortality Fished population Information on fishing mortality Unfished population Information on natural mortality Number of fish Age (years) Low Fishing mortality High Fishing mortality Moderate Fishing mortality
Other age-based Indicators • If we know about growth, maturity and fecundity, other indicators include: • % mature age fish ‘Let them spawn’ • % fish at optimum age ‘Let them grow’ • % very old fish ‘Let mega-spawners live’
Age-based Indicators • Mature at 8 years • Optimum age 14-18 years Mature Optimum Age Mega Spawners Immature ` 71% 12% 16% 29% Number of fish Age (years)
Age-based Indicators • Mature at 8 years • Optimum age 14-18 years Mature Optimum Age Mega Spawners Immature ` 30% 0% 0% 70% Number of fish Age (years)
Age-based Indicators Fishing mortality (F) Harvest rule F < 50% Natural mortality Number of licenses may increase F > 150% Natural mortality F = Natural mortality Number of licenses remains constant Number of licenses reduced • Age-based indicators can inform us about the sustainability of the fishery • And they can be used to trigger the implementation of harvest control rules, e.g.
Age-based Indicators • Age-based indicators can now be used for deepwater snapper because: • Cruises have provided reference age composition data from near unexploited populations – natural mortality • Methods have been developed to derive age compositions from otolith measurements • Monitoring programs have been established and are ongoing in Tonga and Vanuatu • Reproductive biology will be available in 2015
Capacity development • Supported 4 Pacific Islanders to complete postgraduate degrees • Samoa – Ueta Fa’asili Jr (MSc, University of Wollongong) - 2013 “Review of Samoa’s Deepwater Snapper Fisheries Data” • Tuvalu – Etuati Poulasi (MSc, Australian Maritime College) – 2013 “Age, growth and reproductive biology of saddleback snapper Paracaesio kusakarii” • Vanuatu – Jeremie Kaltavara (MSc, Australian Maritime College) - 2014 “Biology and Fishery of the Deepwater Eteline Snappers in Vanuatu” • Tonga – Hau Halafihi (PhD, University of Canterbury) - 2015 “Ecology and biology of Etelis coruscans and Pristipomoides filamentosus at seamounts: Case Study at Tonga Deepwater Drop-line Fishery”
Project Sustainability • Monitoring – Maintaining data collection and using TUF-ART to manage data (on track for Vanuatu and Tonga) • Assessments – Trained staff are retained in the Departments to continue the assessment work (on track for Vanuatu and Tonga) • Project extension – Extension of project to other countries (PNG, New Caledonia, Fiji, Wallis & Futuna) • Knowledge generation – project has seeded Pacific-wide collaborations
Work Plan for 2015 • Project concludes in November 2015 • Priorities for 2015: • Process the remaining otoliths and gonads • Provide estimates of growth, mortality and reproductive biology of key deepwater snapper species • Provide the first evaluation of the sustainability of a deepwater snapper fishery using age-based indicators
Recommendations • Heads of Fisheries are invited to note: • The progress that has been made to date • The project will end in November 2015 • Project sustainability is dependent on continued data collection programs and port sampling activities. Resources for these activities will need to be sourced once the current project is completed. • The indicator approach for assessing deepwater snapper fisheries would also be suitable for other data-poor coastal and oceanic fisheries
For more information... SPC Deepwater snapper webpage: http://www.spc.int/fame/en/projects/fisheries-fo-food-security/improving-the-mgt-of-deepwater-snapper-resources • Project objectives & strategies • Project outputs • Journal publications • Newsletter articles • Fact sheets • Species ID booklet