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CAN WHALING BE MANAGED TO PROTECT WHALES AND WHALERS? Judith E. Zeh Chair of the Scientific Committee (SC) of the International Whaling Commission (IWC) 1999-2002

CAN WHALING BE MANAGED TO PROTECT WHALES AND WHALERS? Judith E. Zeh Chair of the Scientific Committee (SC) of the International Whaling Commission (IWC)

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CAN WHALING BE MANAGED TO PROTECT

WHALES AND WHALERS?

Judith E. Zeh

Chair of the Scientific Committee (SC) of the

International Whaling Commission (IWC)

1999-2002

Research Professor, StatisticsUniversity of WashingtonSeattle, Washington, USA

My presentation style:

Overheads with words and equations!

Thanks for pictures from

Greg Donovan, IWC SecretariatChairman of the Aboriginal Subsistence Whaling Management Procedure (AWMP) Standing Working Group of the SC

Extinction is forever…Extinction is forever…Unless you use…Unless you use…

Balaena electronicusBalaena electronicus

Craig George, Dept. of Wildlife Management North Slope Borough, Barrow, Alaska, USA

ISANA (Brave Fish)published by Japan Whaling Association

Christmas cards and calendar pictures fromSeiji Ohsumi and Hiroshi HatanakaFormer and current Director-General, ICRThe Institute of Cetacean Research, Tokyo, Japan

Minke Whale in the Ross Sea

The Bowhead Whale, Special Publication Number 2 of the Society for Marine

Mammalogy. 1993. Editors J.J. Burns,J.J. Montague and C.J. Cowles.

Figure 1.2. Bowhead whale in scattered ice in the Beaufort Sea. Photo by D. Ljungblad for U.S. Minerals Management Service.

GrayMinke

Sperm

Right

(Humans)

Bryde’s

Sei

Blue

Fin

HumpbackBowhead

Other references:• Gambell, R. 1999. The International Whaling

Commission and the contemporary whaling debate. pp. 179-198 in J.R. Twiss Jr. and R.R. Reeves (eds.) Conservation and Management of Marine Mammals. Smithsonian Institution Press.

• Web sites: www.animalinfo.org, www.coolantarctica.com

• Zeh, J.E. and Punt, A.E. 2005. Updated 1978-2001 abundance estimates and their correlations for the Bering-Chukchi-Beaufort Seas stock of bowhead whales. The Journal of Cetacean Research and Management: in press.

The Whales:Stocks of large baleen whales

The Whalers:CommercialAboriginal subsistence

What is a whale stock?

• SC established a working group to answer this question in 1998.

• Biological stock: population of interbreeding whales of a particular species that maintains itself over time in a definable area

• Management stock: all or part of a biological stock in an area where it may be subject to human-induced mortality and management

• Working group decided in 2002 to focus on ‘unit-to-conserve’ rather than ‘stock’.

I use ‘stock’ as shorthand for ‘management stock’ or ‘unit-to-conserve’

• May not correspond to biological stock

• Definition depends on management objectives

• Stock boundaries may be temporal as well as spatial, may be hard to determine

• Significant genetic differences between areas may not mandate management as separate stocks if migration rates between the areas are high

Aboriginal Subsistence Whaling

• No formal definition

• Traditionally ‘accepted’:• Greenland• Alaska• Washington State• Chukotka, Siberia• St Vincent and The Grenadines

Long traditions! 19th century stone spear points from bowhead whales landed since 1980 in Alaska

Bangudae petroglyphs, Ulsan, Korea

Below, remains of structures made from bowhead bones, Wales, Alaska. Photo by I.I. Krupnik. Right, towing a whale to the shorefast ice for butchering and pulling onto the ice. Photos by J.C. George.

‘Small-type’ (commercial) whaling

• Iceland

• Norway

• Japan

Also long traditions! Below, 1773 picture of whaling station, Hizen, Japan. Right, right whale being harpooned off Ikitsuki Misaki. Lower right, 1997 whaling boat race, Muroto City, western Japan (from ISANA, Oct. 1997).

Large-scale commercial whaling using factory ships in the Antarctic

Hauling a fin whale up the slipway

Factory ship Jan Wellem at anchor with catcher boats alongside

IWC established in 1946 by the International Convention for the Regulation of Whaling, signed by 14 whaling nations.

• Convention • Schedule…the history of whaling has seen over-fishing of one area … and of one whale species after another… convention to provide for the proper conservation of whale stocks and thus make possible the orderly development of the whaling industry…

Precise regulations governing whaling operations

• AmendmentsRequire ¾ majority vote

Convention mandated management based on scientific findings. The SC was established in 1951. But trade-offs with industry demands:

• Contracting Governments objecting to amendments are not bound by them; Norway now whales under objection.

• Any Contracting Government may grant a special permit to its nationals to kill, take and treat whales for purposes of scientific research; Iceland and Japan now conduct scientific permit whaling.

The blue whale story involves trade-offs:

Continued decline of blue whales

1931 1947 1960

D.G. Chapman. 1972. The Plight of the Whales. pp. 84-91 in Statistics: a guide to the unknown. Edited by J.M. Tanur et al.

1961: IWC appointed Committee of Three scientists (Chapman, Allen, Holt) from non-whaling nations to work with SC to determine size of Antarctic stocks and safe catch limits.

Reported to IWC in 1963.

The Blue Whale Unit (BWU)

1 blue whale =

2.5 humpbacks =2.5 humpbacks = 6 sei6 sei 2 fin whales =2 fin whales =

Results of Committee of Three Report

• IWC banned Antarctic humpback catches in 1963, blue whale catches in 1964.

• BWU => doubled fin whale catches; report said reduce from 27,000 to 7,000 and predicted would drop to 14,000 next season in any case; IWC reduced quota only when prediction proved correct.

• In 1972, catch limits finally set by species rather than by BWU.

• All these species now fully protected from whaling throughout the Southern Hemisphere.

SC developed a new management procedure based on a density-dependent population dynamics model:

• K = initial (unexploited) population size

• Lower production rate at K than at lower population sizes

• MSY = Maximum Sustainable Yield

• MSYR = MSY rate as a percent of abundance

• MSYL = MSY level as a percent of K (60%)

New Management Procedure (NMP)

0 Blue whales

2,244 Minkes

Acme Acme quotasquotas

MSY rateMSY rate

Mortality ratesMortality rates

Pregnancy ratePregnancy rate

Age at sexual Age at sexual maturitymaturity

CPUE dataCPUE data

AbundanceAbundance

Catch historyCatch history

Initial Initial population sizepopulation size

IMS = >72% catch <MSYIMS = >72% catch <MSY

SMS = 54-72% catch <<MSYSMS = 54-72% catch <<MSY

PS < = 54% catch = 0PS < = 54% catch = 0

NMP adopted 1975 – not all bad!

• Designed to bring stocks to optimum level

• Protected stocks at 54% initial

• Formal structure

• Took power away from politicians

• Assumed near-perfect knowledge of dynamics of all whale stocks (MSYR, MSYL, K)

• SC couldn’t agree on stock classifications or catch limits except for PS stocks clearly in need of protection

The ‘Moratorium’ and the ‘Comprehensive Assessment’

• Moratorium: pause in commercial whaling, adopted by IWC in 1982, took effect 1985-86

• Comprehensive Assessment: mandated by IWC in 1982; defined by SC as ‘an in-depth evaluation of the status of all whale stocks in the light of management objectives and procedures… that … would include the examination of current stock size, recent population trends, carrying capacity and productivity’; included development of a

• Revised Management Procedure (RMP)

Management procedures

• Objectives must be explicitly stated, assigned priorities, specified in a quantitative way

• Data and analysis requirements must be realistic and specified

• Data limitations and uncertainty must be taken into account in designing and testing procedure

• Rigorous testing must be done via computer simulations

• Must include feedback monitoring, e.g. implementation reviews to be sure data and status of stock remain within tested parameter space

Management objectives

(extremes)

Avoid extinction of

cetacean

Do not affect Do not affect profitabilityprofitability

TRADE-OFFSTRADE-OFFS

$$$$$$

RMP objectives involve trade-offs(less extreme)

• Catches should not be allowed on stocks below 54% of the estimated carrying capacity (as in the NMP).

• Catch limits should be as stable as possible.

• The highest possible continuing yield should be obtained from the stock.

RMP Data Requirements

• Time series of catches by sex in area being managed (including other human-induced mortalities, e.g. from entanglement in fishing gear or ship strikes)

• Absolute abundance estimates obtained by direct methods, e.g. sightings surveys; survey interval not to exceed 6 years

Catch Limit Algorithm

• Specifies the way catch limits are calculated from required information

• Initially ‘true’ situation poorly known– Depletion level, productivity– Abundance estimates

• Range of possible catch limits– Acceptable level of risk

• ‘Learns’ as more data become available

Test CLA via many computer simulations of 100 years of management, e.g.

• Different population dynamics models

• Different MSYR, MSYL, K

• Bias in estimated abundance

• Errors in historic catch records

Balaenoptera electronicusBalaenoptera electronicus

SC completed RMP in 1993, unanimously recommended adoption by Commission

• SC provided specification of CLA and other aspects of the RMP, notes regarding data requirements

• Commission wanted to complete Revised Management Scheme (RMS) but also expressed concerns about the RMP

• Commission did not adopt the RMP in 1993

• SC Chair Phil Hammond resigned in protest

• Commission adopted RMP in 1994

RMS

• Independent monitoring• Accounting for bycatch• Guidelines for surveys• Data standards• Inspectors and observers• DNA register of catches

and market sampling• Apportioning costs• Humane killing

RMP

CLA

IWC now has 66 member nations, most not whaling nations

• Meets at least annually

• Passes Resolutions by majority vote, e.g. to complete RMS

• Meanwhile, Norway whales using its version of the RMP, Iceland and Japan whale without catch limits

• IWC should resume managing whaling!

IWC does manage subsistence whaling! Adopted Bowhead SLA, part of Aboriginal Subsistence Whaling Management

Procedure (AWMP)

Objectives of AWMP (1982, 1994) Different from RMP objectives!

Ensure risks of extinction not Ensure risks of extinction not seriously increased (highest priority)seriously increased (highest priority)

Enable harvests in perpetuity Enable harvests in perpetuity appropriate to cultural and nutritional appropriate to cultural and nutritional needsneeds

Maintain stocks at highest net Maintain stocks at highest net recruitment level and if below that recruitment level and if below that ensure they move towards itensure they move towards it

Some assumptions (bowhead case)

• Strikes versus catches

– Assume that strikes all result in kills

– Termed ‘Strike Limit Algorithm’ – SLA

• Future need – uncertain

– Need ‘envelope’ to set bounds

– Agreed with Commission in 1997

• Options after 100 years: 134 and 201 strikes

– If need request outside bounds – new trials

• Like RMP CLA, required data are abundance and catches, SLA tested via simulation trials

Features of AWMP and AWS (Aboriginal Whaling Scheme) based on dialogue with hunters

• Account for Arctic conditions

– Block quota (5 yrs) and carryover

• Up to 50% carryover between years (and blocks)

– Survey interval and grace period

• Surveys at least every 10 years

• Cannot manage without data – 5 yr ‘grace’

• Phase-out rule: block quota reduced by 50% in absence of survey – user decides strategy

• Not expected to be needed

Abundance estimates from visual counts, but could there be more?

• Can only count what you can see…

• Hunters believed whales pass through closed leads…

Acoustic monitoring added to visual to improve abundance estimates: 10,500 (CV 13%) in 2001

Chris Clark records bowhead calls

A visual census perch near Point Barrow, Alaska, used in 1984

AWS

AWMP

SLA

Bowhead SLA adopted 2002First Implementation Review will occur in 2007; focus on whether single stock

• Implementation reviews every 5 years or as needed• Review new data to

be sure within tested ‘space’

> stock structure> abundance> biology> unusual deaths> information

from hunters

Recurring polynyas available to bowheads in winter and spring

• Whales caught around St. Lawrence Island differ genetically from others

• Separate stock? Or age or some other differences?

• If separate, abundance?

• Catch of 1-8 whales/yr around SLI safe?

Being taken by whalers not the only threat! Entanglement in fishing gear (below) and ship strikes (left) cause deaths in the most endangered populations, e.g. North Atlantic right whale below.

Take-home messages• Worry most about endangered whales that would

never be subject to whaling!• AWMP and RMP may be more conservative than

whalers like, but whalers are not protected unless whales are.

• Whales are protected by management procedures > based on monitoring abundance, catches; >

tested over plausible range of uncertainties.• Whales fulfill cultural and nutritional needs for

nations as well as aboriginal people with whaling traditions!

THANK YOU!

• If the IWC does not manage whaling, it will take place without international oversight.

• That is not good for the whales!