the shark group 1- a brief summary of the results achieved during the data preparatory meeting,...

THE SHARK GROUPTHE SHARK GROUP

1- A brief summary of the results achieved1- A brief summary of the results achieved during the Data Preparatory Meeting, during the Data Preparatory Meeting, Punta del Este, Uruguay, July 21 to 25;Punta del Este, Uruguay, July 21 to 25;

2- Workplan for 2008;2- Workplan for 2008;

3- Recommendations to the Commission 3- Recommendations to the Commission (from the Executive Summary);(from the Executive Summary);

EXECUTIVE SUMMARY FOR SHARKSEXECUTIVE SUMMARY FOR SHARKS


1- Data Preparatory Meeting, 1- Data Preparatory Meeting, Punta del Este, Uruguay, Punta del Este, Uruguay, July 21 to 25;July 21 to 25;

THE SHARK CROWDTHE SHARK CROWD

Punta del Este, Uruguay, July 2007Punta del Este, Uruguay, July 2007

SHARKSSHARKS

SHARKSSHARKS

0

2

4

6

8

1958

1959

1960

1961

1962

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

2003

2004

2005

Year

CP

UE

(Fis

h/10

00 H

ooks

)

Série1 Série2

Yearly CPUE (fish per 1,000 hooks), for the blue shark, from Brazilian longliners Yearly CPUE (fish per 1,000 hooks), for the blue shark, from Brazilian longliners operating from Natal (1986 to 2005) and from five tuna longliners operating in the operating from Natal (1986 to 2005) and from five tuna longliners operating in the

Southwestern Equatorial Atlantic Ocean from May 1958 to September 1962 .Southwestern Equatorial Atlantic Ocean from May 1958 to September 1962 .


2- Workplan for 20082- Workplan for 2008

Blue and mako sharks: Full assessmentBlue and mako sharks: Full assessment

1- Longfin mako, 1- Longfin mako, Isurus paucusIsurus paucus2- Bigeye thresher, 2- Bigeye thresher, Alopias superciliosusAlopias superciliosus3- Common thresher, 3- Common thresher, Alopias vulpinusAlopias vulpinus4- Oceanic whitetip, 4- Oceanic whitetip, Carcharhinus longimanusCarcharhinus longimanus5- Silky shark, 5- Silky shark, Carcharhinus falciformisCarcharhinus falciformis6- Porbeagle, 6- Porbeagle, Lamna nasusLamna nasus7- Scalloped hammerhead, 7- Scalloped hammerhead, Sphyrna lewiniSphyrna lewini8- Smooth hammerhead, 8- Smooth hammerhead, Sphyrna zygaenaSphyrna zygaena9- Crocodile shark, 9- Crocodile shark, Pseudocarcharias kamoharaiPseudocarcharias kamoharai10- Pelagic stingray, 10- Pelagic stingray, Pteroplatytrygon violaceaPteroplatytrygon violacea

Rapid assessment of relative vulnerability to overfishing, Rapid assessment of relative vulnerability to overfishing, based on demographic data and risk analyses, based on demographic data and risk analyses, and evaluation of their susceptibility to the fisheriesand evaluation of their susceptibility to the fisheries


2- Workplan for 20082- Workplan for 2008

Blue and mako sharks: Full assessmentBlue and mako sharks: Full assessment

Assessment methods to be used:Assessment methods to be used:

a) demographic model;a) demographic model;

b) bayesian surplus production (BSP) model;b) bayesian surplus production (BSP) model;

c) age-structured production model (ASPM) incorporating catch data; c) age-structured production model (ASPM) incorporating catch data;

d) “catch-free” age structured production model; andd) “catch-free” age structured production model; and

e) “tagging model”: e) “tagging model”: an attempt will be made to use the available tagging an attempt will be made to use the available tagging data and the historical longline effort data to provide an independent data and the historical longline effort data to provide an independent estimate of fishing mortality rates (and associated variances) over estimate of fishing mortality rates (and associated variances) over time (Aires-da-Silva time (Aires-da-Silva et al., et al., 2005). 2005).

((These estimates could then be used as priors for the BSP and ASPM models)These estimates could then be used as priors for the BSP and ASPM models)


3- Management Recommendations3- Management Recommendations (from the Executive Summary)(from the Executive Summary)

b) For an effective implementation of Rec. 04-10, the fin to body b) For an effective implementation of Rec. 04-10, the fin to body weight ratio needs to be better defined in terms of the kind of weight ratio needs to be better defined in terms of the kind of fins considered in the ratio as well as the kind of processing of fins considered in the ratio as well as the kind of processing of both fins and body. Conversion factors between fins and body both fins and body. Conversion factors between fins and body weights need to be implemented on a species and/ or fleet-weights need to be implemented on a species and/ or fleet-specific basis.specific basis.

a) Before the results of the next assessment become available next a) Before the results of the next assessment become available next year, on the basis of which new management recommendations year, on the basis of which new management recommendations might become advisable, the Commission should ensure the might become advisable, the Commission should ensure the effective implementation of Recs. 04-10 and 05-05. effective implementation of Recs. 04-10 and 05-05. Of particular Of particular concern is the very low level of compliance with the obligation of concern is the very low level of compliance with the obligation of CPCs to provide Task I and II data for sharks caught by their CPCs to provide Task I and II data for sharks caught by their vessels, greatly hampering, when not completely impeding, the vessels, greatly hampering, when not completely impeding, the assessment of the status of the exploited shark stocks.assessment of the status of the exploited shark stocks.


The bottom line: The bottom line: What is the great chalenge for the 2008 assessment ?What is the great chalenge for the 2008 assessment ?

Getting updated series of catch and effort data, Getting updated series of catch and effort data, and standardized CPUE series from the main fisheries !! and standardized CPUE series from the main fisheries !!

THE SHARK GROUPTHE SHARK GROUPWhat are the possible consequences ? [Rec. 05-09]What are the possible consequences ? [Rec. 05-09]As a consequence of these data deficiencies, increasingly conservative As a consequence of these data deficiencies, increasingly conservative management measures might be needed to be implemented by the management measures might be needed to be implemented by the Commission, in order to limit the risk of fishery and shark stocks collapseCommission, in order to limit the risk of fishery and shark stocks collapse

In the lack of data, In the lack of data, the Commission will need to be precautionarily more pessimistic !!the Commission will need to be precautionarily more pessimistic !!

AAHH KKRRSS SSTT NN

the shark group 1- a brief summary of the results achieved during the data preparatory meeting,...

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