WP3: Deepwater snapper
Towards improved stock assessments
and management
Outline
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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
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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:
1.
2.
3.
4.
Fisheries data collection
Improving biological knowledge
Fisheries assessment and management
Capacity development
Results achieved
Fisheries Data Collection
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
Improving Biological Knowledge
Biological Sampling
• Scientific cruises
Papua
New Guinea
• Port sampling
5S
Wallis
& Futuna
10S
Samoa
Vanuatu
15S
Fiji
20S
Tonga
New Caledonia
25S
Australia
Pacific Ocean
30S
145E
150E
155E
160E
165E
170E
175E
180
175W
170W
165W
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)
Black tip on tail
Pygmy Ruby Snapper (Etelis marshi)
Ruby Snapper (Etelis carbunculus)
Operculum spine
Otolith shape
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
Deepwater Snapper Habitat
Deepwater Snapper Habitat
Main Target Species
Ruby snapper (Etelis carbunculus)
Pygmy ruby snapper (Etelis marshi)
Flame snapper (Etelis coruscans)
Crimson jobfish (Pristipomoides filamentosus)
Age estimation
• Age information needed to estimate longevity, growth rates etc.
• We estimate age by counting bands in sectioned otoliths
1 mm
1 mm
Age estimation
E. carbunculus
E. marshi
E. coruscans
P. filamentosus
Growth
• Slow growth rates
• Extended longevity (> 30 years)
180
160
Fork length (cm)
140
120
100
80
60
40
20
0
0
10
20
30
40
Age (years)
50
60
70
Fisheries assessment and
management
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
Back to Growth ...
200
180
Fork length (cm)
160
140
120
100
80
60
40
20
0
0
10
20
30
40
Age (years)
50
60
70
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
Width
Thickness
• We measured
otoliths from 4
species
• Simple and rapid
procedure
Number of fishNumber of fish
Age Composition
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
100
Fished
population
Unfished
population
90
Number of fish
80
Information on fishing
naturalmortality
mortality
70
60
50
40
30
20
10
0
0
2
4
6
8
Age (years)
10 12 14 16 18 20 22 24 26 28 30
High Fishing
mortality
Moderate
Fishing mortality
Low 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
80
70
71%
29%
60
Number of fish
Mature
Immature
Optimum
Mega
Age
Spawners
12%
16%
50
`
40
30
20
10
0
0
2
4
6
8
10 12 14 16 18 20 22 24 26 28 30
Age (years)
Age-based Indicators
• Mature at 8 years
• Optimum age 14-18 years
80
70
30%
70%
60
Number of fish
Mature
Immature
Optimum
Mega
Age
Spawners
0%
0%
50
`
40
30
20
10
0
0
2
4
6
8
10 12 14 16 18 20 22 24 26 28 30
Age (years)
Age-based Indicators
• 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.
Fishing mortality (F)
Harvest rule
F < 50% Natural mortality Number of licenses may increase
F = Natural mortality
Number of licenses remains constant
F > 150% Natural mortality Number of licenses reduced
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
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 Pacificwide collaborations
Project Sustainability
Knowledge area
Collaborator
Stock Structure:
Genetics
University of Canterbury, New Zealand
University of Hawaii, USA
Otolith Chemistry
James Cook University, Australia
Otolith Shape
Department of Renewable Marine
Resources, Spain
Coastal Fisheries Programme, SPC
Parasites
Biology/Ecology
Department of Fisheries, Western Australia
Economic analysis, adaptive
management (Tonga)
National Institute of Water and
Atmospheric Research, New Zealand
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-ofdeepwater-snapper-resources
• Project objectives & strategies
• Project outputs
• Journal publications
• Newsletter articles
• Fact sheets
• Species ID booklet