Stakeholders Consultation Workshop on Saving the Juvenile Tunas

Greenleaf Hotel, General Santos City

September 10, 2013

What you need to

know about juvenile

tunas in the

Philippines:

N. Barut National Fisheries Research & Development Institute, BFAR

J. Ingles WWF, Coral Triangle Program

Outline of Presentation

Some facts about tuna fisheries What is juvenile tuna? How much juvenile tunas do we harvest? Where and When are Juvenile tunas found? Why are juvenile tunas important to us? What needs to be done.

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1950 1960 1970 1980 1990 2000 2010

Dep

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yft

skj

bet

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1950 1960 1970 1980 1990 2000 2010

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ple

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yft

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Adult Biomass Total Biomass

What is a juvenile tuna

Juvenile tuna – or immature tunas are those fish that have not reached age of maturity or reached the ability to reproduce.

Length/Age at Maturity (Lm) – many interpretations • the average minimum length or its corresponding

age of the fish that is reproductively capable. • Minimum length of spawning fish • L50= length / age where 50% of the new recruits

become reproductively capable

SKJ = 45 cm; YFT= 100 cm; BET= 105 cm

How much do we harvest?

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2005 2006 2007 2008 2009 2010 2011

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Year

SKJ

YFT

BET

• Accuracy of estimates improved significantly (2 yrs) • Declining trend for all 3 principal species • Arguably decline partly due to compliance (high

seas closure)

Total Tuna Harvest

Source: WCPFC Yearbook 2012

How much juvenile tunas are harvested?

2010 Juvenile Tuna catch estimate (mt)

Sources: WCPFC Yearbook 2012 for total harvest; NSAP database

Gears SKJ YFT BET TOTAL PS 76679 14061 2166 92906 RN 26365 5363 218 31945 HL large 0 2037 10 2046 HL small 20815 43096 1302 65213 2010 Total Juveniles

%

PS

RN

HL

small

HL

large

• For 2010, 90.8 % of total catch of our tunas are classified as juveniles

• Both commercial and artisanal gears catch significant quantities;

• “Handline Large” harvest predominantly mature individuals

192,110 mt

Where are juvenile tunas found?

Sources: LF from FRMP Project 2004; Map redrawn from WWF-PPTST

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19 27 35 43 51 59 69 77

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qu

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Fork Length (cm)

Skj: Lagonoy Gulf (2004)

Mature = 57 % Juv = 43%

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20 45 70 95 120 145

Freq

uen

cy

Fork Length (cm)

YFT: Lagonoy Gulf (2004)

Where are juvenile tunas found?

Source: WWF FAD report

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0 10 20 30 40 50 60 70

Freq

ue

ncy

Fork Length (cm)

SKJ: HL & TL

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2500

3000

2.5 27.5 52.5 77.5 102.5 127.5 152.5 177.5

Freq

uen

cy

Fork Length (cm)

YFT: HL&TL

Pacific Seaboard (Off Samar)

Source: NSAP database

Where are juveniles found?

Sources: LF from NSAP database , map from WWF FAD report

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2.5 27.5 52.5 77.5 102.5 127.5 152.5 177.5 202.5

Freq

uen

cy (

000)

Fork length (cm)

YFT: Moro Gulf/ Celebes Sea

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4000

5000

1 7 13 19 25 31 37 43 49 55 61 67 73

Freq

uen

cy

Fork Length (cm)

SKJ: Moro Gulf/ Celebes Sea

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50

100

150

200

2.5 27.5 52.5 77.5 102.5 127.5 152.5 177.5

Freq

uen

cy

Fork Length (cm)

BET: Moro Gulf/ Celebes Sea

Where are juveniles found?

Sources: LF data from NSAP database , Map from WWF

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100

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300

400

1 7 13 19 25 31 37 43 49 55 61 67

Freq

uen

cy

Fork Length (cm)

SKJ: DLL&TL

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2.5 27.5 52.5 77.5 102.5 127.5 152.5 177.5

Freq

uen

cy

Fork Length (cm)

YFT:DLongline

Northwestern Philippine Sea

Where are juvenile tunas found?

Sources:

Philippine EEZ

FAD deployment evolution in the

Philippines

Sources WWF 2012 FAD tech report

Why are juvenile tunas present all year?

Sources: yamanaka, 1989; www.fishbase.org

Month NE Monsoon

Cohort

SW Monsoon

Cohort

Jan 25 -35 cm

Feb SPAWNING

Mar

35 - 45 cm Apr 15-25 cm

May

Jun 25 -35 cm

45 - 60 cm Jul

Aug 35 - 45 cm

Sep SPAWNING

Oct

Nov 45-60 cm 15-25 cm

Dec

Jan Migrates to the 25 -35 cm

Feb Pacific

• Juvenile tunas occur all year; • Two cohorts per year; • Recruitment to the fishery

(~20 cm) occur in April-May and Nov-Dec of each year

• Smaller individuals in nearshore waters and on upper level of water column;

• Sizes from 60-100 cm (5-25 kg) disappears from catches and rarely caught in Phil in- zone waters;

Yellowfin Tuna

How fast do yft grow?

Source: Lehodey & Leroy, 1999. Age and growth of yellowfin tuna (T. albacares from the Western and Central Pacific Ocean as indicated by daily growth increments and tagging data

YFT = 57.56 cm FL and 3.726 kg in year 1 15-35 cm = 2.5 mm/d; 35-79 cm = 0.96 cm/d Source: Yamanaka, 1989

How fast do skj grow?

SKJ = up to 27 cm = 1.60 mm/d; 27-71 cm= 0.8 mm/day Source: Uchima & Struhsaker, 1981

Why are juvenile tunas important to us?

Food – 192,000 tons could feed 5.3 million Filipinos Value – @ P70/kg, value approximates P13.44 billion Jobs – unknown but significant number of direct and

indirect beneficiaries that are dependent on juvenile and adult tuna fisheries!!

Why are juvenile tunas important to the rest of the world?

Ph-born tunas supply undetermined portion of the Western and Central Pacific tuna stocks that are harvested by the DWF that includes Philippine owned companies.

If saving our juvenile tunas is vital to our economy and to our survival . . .

what needs to be done?

• manage the harvest of tunas (both juvenile and adults) by limiting our harvest at a level that we will continue to benefit and allow sufficient numbers to reproduce to replenish the population taken by the fisheries;

• find a way to compensate our fishers from social and economic cost arising from compliance with conservation measures;

• Conduct focused research, to provide the decision basis for the policies.

• Identify innovative solutions to the issue , prototype the solution, pilot test and upscale the feasible ones.

We need to:

Thank you for your kind attention

PS RN

Hand line

H&L/ MHL

DGN Troll

Skipjack 98.9 99.8 0.00 82.6 41.8 90.5

Yellowfin 100.0 100.0 18.0 99.3 no data 100.0

Bigeye 100.0 100.0 3.40 93.0 no data no data

2010 SKJ YFT BET TOTAL PS 76679 14061 2166 92906 RN 26365 5363 218 31945 HL large 0 2037 10 2046 HL small 20815 43096 1302 65213 2010 Total Juveniles 192110