The Green-Eyed The Green-Eyed SurvivorSurvivor

Dogfish Shark Life History & Dogfish Shark Life History & Populations in the Gulf of AlaskaPopulations in the Gulf of Alaska

Cindy A TribuzioCindy A TribuzioSchool of Fish and Ocean SciencesSchool of Fish and Ocean Sciences

University of Alaska FairbanksUniversity of Alaska FairbanksJuneau CenterJuneau Center

In Cooperation With……In Cooperation With……

Alaska Department of Fish and Alaska Department of Fish and GameGame

NMFS AFSC Auke Bay Lab

OutlineOutline

Sharks in AlaskaSharks in AlaskaDogfish Biology and Fishery InfoDogfish Biology and Fishery InfoProject ObjectivesProject ObjectivesData CollectionData CollectionObjective Results and ConclusionsObjective Results and ConclusionsCurrent and Future ResearchCurrent and Future Research

Gulf of Alaska SharksGulf of Alaska Sharks

8 shark species, 6 families8 shark species, 6 families 12+ skate species, 2 families12+ skate species, 2 families 1 chimera, ratfish 1 chimera, ratfish Hydrolagus collieiHydrolagus colliei

Gulf of Alaska SharksGulf of Alaska Sharks

Blue Shark, Blue Shark, Prionace glaucaPrionace glauca

Gulf of Alaska SharksGulf of Alaska Sharks Family LamnidaeFamily Lamnidae

Mackerel sharksMackerel sharks

Great White SharkCarcharodon carcharias

Salmon SharkLamna ditropis

Gulf of Alaska SharksGulf of Alaska Sharks

Basking Shark, Basking Shark, Cetorhinus maximusCetorhinus maximus

Gulf of Alaska SharksGulf of Alaska Sharks

Sleeper Shark, Sleeper Shark, Somniosus pacificusSomniosus pacificus

Gulf of Alaska SharksGulf of Alaska Sharks Brown Cat Shark, Brown Cat Shark, Aprisurus brunneusAprisurus brunneus

Cookie CutterCookie Cutter

Gulf of Alaska SharksGulf of Alaska SharksRaja familyRaja family Big SkateBig Skate

Raja binoculataRaja binoculata

Longnose SkateLongnose Skate

Raja rhinaRaja rhina

Gulf of Alaska SharksGulf of Alaska Sharks

Bathyraja familyBathyraja family

Spiny Dogfish, Spiny Dogfish, Squalus acanthiasSqualus acanthias

Geographic DistributionGeographic Distribution Worldwide distribution in temperate coastal Worldwide distribution in temperate coastal

areasareas

www.flmnh.ufl.edu

Dogfish BiologyDogfish Biology Worldwide distribution in temperate coastal Worldwide distribution in temperate coastal

areasareas Small size (up to 1.3m long) and long lived Small size (up to 1.3m long) and long lived

(100 years)(100 years) Stigma of being a Stigma of being a

“Nuisance Species”“Nuisance Species” Ecologically important Ecologically important

as both predator and as both predator and preyprey

Common PerceptionsCommon PerceptionsConsidered a nuisance speciesConsidered a nuisance species

National Fisherman, Nov 2004:National Fisherman, Nov 2004: ““Dogfish are wolves Dogfish are wolves

of the sea”of the sea”

Blames dogfish for Blames dogfish for the decline in more the decline in more desirable species desirable species such as sea bass, such as sea bass, porgies and “baby porgies and “baby codfish”codfish”

http://new-brunswick.net/new-brunswick/sharks/species/spinydogfish.html

Cultural ImportanceCultural Importance

Qqaaxhadajaat, the Dogfish WomanQqaaxhadajaat, the Dogfish WomanA woman went traveling with her husband. She used to make fun of the dogfish. They went to visit a small rock in the sea. When they were out there, the dogfish, whose home the rock was, came and took the woman down into the sea. There she discovered that the dogfish were really people. They had taken off their dogfish blankets. After she had stayed in the house for some time, fins began to grow upon her arms, her legs and her back. Her husband was searching for her everywhere, but he was not able to find her. After a number of years he found her. Her face had remained unchanged; but fins had grown on her arms, on her legs, on her back, and on her head. She never returned. Ever since that time her family have used the dogfish crest, and their house is called Dogfish House.

MitchAge: 5

ClintAge: 3

Size and Age of Spiny DogfishSize and Age of Spiny Dogfish

Height: 44 in, 112 cm

Height: 39 in,99 cm

Size and Age of Spiny DogfishSize and Age of Spiny Dogfish

Mitch, Age 5Height: 44 in, 112 cm

Clint, Age 3Height: 39 in,99 cm

Spiny Dogfish, Age 5Length: 13 in, 35 cm

Spiny Dogfish, Age 3Length: 11 in, 28 cm

Size and Age of Spiny DogfishSize and Age of Spiny Dogfish

Mitch, Age 5Height: 44 in, 112 cm

Clint, Age 3Height: 39 in,99 cm

Spiny Dogfish, Age >100 years!!!Length: 44 in, 112 cm

Spiny Dogfish, Age 48 years!!!Length: 39 in, 99 cm

Reproductive BiologyReproductive Biology Females mature at ~35 yrsFemales mature at ~35 yrs ~22 month gestation, 7-12 pups average~22 month gestation, 7-12 pups average Fecundity and offspring survival increase as Fecundity and offspring survival increase as

female ages/grows largerfemale ages/grows larger

Photo by Rustin Director

Commercial Shark FishingCommercial Shark Fishing

North Atlantic ExperienceNorth Atlantic Experience

The situation:The situation: Fishery developed rapidly (1988), was stable Fishery developed rapidly (1988), was stable

for a short period then declinedfor a short period then declined

40 years of fishery independent survey data40 years of fishery independent survey data

Commercial fishery targeted large individuals, Commercial fishery targeted large individuals, landings were dominated by mature females landings were dominated by mature females

North Atlantic ExperienceNorth Atlantic Experience

The problems……The problems…… 1988-2000: average size of landed female 1988-2000: average size of landed female

dogfish dropped from dogfish dropped from 4 kg to 2 kg4 kg to 2 kg and 95 to 79 and 95 to 79 cmcm

Almost no recruitment after 10 years of fishing Almost no recruitment after 10 years of fishing pressurepressure

1989-2003: fishery removed nearly 213 K mt of 1989-2003: fishery removed nearly 213 K mt of spiny dogfish, biomass of spawning females spiny dogfish, biomass of spawning females dropped by 75%, total biomass of the dropped by 75%, total biomass of the population dropped by about 30%population dropped by about 30%

North Atlantic ExperienceNorth Atlantic Experience The resultsThe results

Few large females available to reproduce, Few large females available to reproduce, small females producing pups with lower small females producing pups with lower survivalsurvival

North Atlantic ExperienceNorth Atlantic Experience The resultsThe results

Few large females available to reproduce, Few large females available to reproduce, small females producing pups with lower small females producing pups with lower survivalsurvival

Reduction in the number of juveniles recruiting Reduction in the number of juveniles recruiting to maturityto maturity

North Atlantic ExperienceNorth Atlantic Experience The resultsThe results

Few large females available to reproduce, Few large females available to reproduce, small females producing pups with lower small females producing pups with lower survivalsurvival

Reduction in the number of juveniles recruiting Reduction in the number of juveniles recruiting to maturityto maturity

NMFS declared over fished in 1998NMFS declared over fished in 1998

North Atlantic ExperienceNorth Atlantic Experience The resultsThe results

Few large females available to reproduce, Few large females available to reproduce, small females producing pups with lower small females producing pups with lower survivalsurvival

Reduction in the number of juveniles recruiting Reduction in the number of juveniles recruiting to maturityto maturity

NMFS declared overfished in 1998NMFS declared overfished in 1998 Atlantic States Marine Fisheries Commission Atlantic States Marine Fisheries Commission

adopted catch limits of a 4 million pound adopted catch limits of a 4 million pound bycatch cap quota and 300/600 pound trip bycatch cap quota and 300/600 pound trip limits for the 2005-2006 fishing seasonlimits for the 2005-2006 fishing season

University of Washington Digital Image Collection

North Pacific Ocean FisheryNorth Pacific Ocean FisheryCommercially fished for over 100 yearsCommercially fished for over 100 years

www.sharkinfo.com

North Pacific Ocean FisheryNorth Pacific Ocean Fishery British Columbia and Washington State manage British Columbia and Washington State manage

transboundary fishery independentlytransboundary fishery independently Washington State fishery is larger (tonnage) than BC Washington State fishery is larger (tonnage) than BC

fisheryfishery Stock assessments in WA show decreasing Stock assessments in WA show decreasing

abundances, reflected in catch. Opposite in BC.abundances, reflected in catch. Opposite in BC.

North Pacific Ocean FisheryNorth Pacific Ocean Fishery Fishery Characteristics:Fishery Characteristics:

Targets larger females for size and ovariesTargets larger females for size and ovaries Most products exported internationallyMost products exported internationally Valuable marine export (with increasing market potential)Valuable marine export (with increasing market potential)

WA fishery generally targets inside (Puget Sound) WA fishery generally targets inside (Puget Sound) dogfish, BC fishery targets outside (Coastal) dogfishdogfish, BC fishery targets outside (Coastal) dogfish

Outside dogfish more migratory, where inside dogfish Outside dogfish more migratory, where inside dogfish tend to stay within home region (Strait of Georgia or tend to stay within home region (Strait of Georgia or Puget Sound)Puget Sound)

Puget Sound and Strait of Georgia dogfish cannot be Puget Sound and Strait of Georgia dogfish cannot be sold domestically for human consumptionsold domestically for human consumption

Current Status of Alaskan FisheryCurrent Status of Alaskan Fishery

Federal bycatch fishery in KodiakFederal bycatch fishery in Kodiak Yakutat Bay: bycatch retention up to 35% Yakutat Bay: bycatch retention up to 35%

of total catch in hook and line fisheries, of total catch in hook and line fisheries, retention up to 100% of total catch in set retention up to 100% of total catch in set net fisheriesnet fisheries

Cook Inlet: targeted fishery via Cook Inlet: targeted fishery via Commissioners Permit began in April 2005Commissioners Permit began in April 2005

Fishery ConcernsFishery Concerns

Shark fisheries are generally not Shark fisheries are generally not sustainablesustainable Life history (late mature, low fecundity) does Life history (late mature, low fecundity) does

not support fisherynot support fishery

Ecological impact of fisheryEcological impact of fishery Dogfish may have valuable role in ecosystemDogfish may have valuable role in ecosystem

Regular bycatch in commercial fisheriesRegular bycatch in commercial fisheries LonglineLongline TrawlTrawl

Seasonal bycatch in commercial fisheriesSeasonal bycatch in commercial fisheries Salmon fisheriesSalmon fisheries

Sport fish bycatchSport fish bycatch

Urgency and Management IssuesUrgency and Management Issues

Urgency and Management IssuesUrgency and Management Issues No estimates of bycatch mortality and its No estimates of bycatch mortality and its

impacts on dogfish populationsimpacts on dogfish populations Increasing fishing pressure in federal Increasing fishing pressure in federal

waters where allowed as “other species”waters where allowed as “other species” Increased pressure in AK state waters for Increased pressure in AK state waters for

commercial fisherycommercial fishery

Need for ResearchNeed for Research

No stock assessments of spiny dogfishNo stock assessments of spiny dogfish Little information on region specific biology Little information on region specific biology

and ecologyand ecology What levels of harvest might be What levels of harvest might be

sustainable?sustainable? Is a targeted fishery even economically Is a targeted fishery even economically

feasible?feasible?

Alaskan Dogfish ResearchAlaskan Dogfish Research Project funded by NPRB and NMFS FellowshipProject funded by NPRB and NMFS Fellowship Study began in July 2004 and planned though Study began in July 2004 and planned though

20072007 Cooperative with UAF, UW, NMFS, and ADF&GCooperative with UAF, UW, NMFS, and ADF&G

Goals:Goals:1)1) Estimate demographic parameters, stock assessment Estimate demographic parameters, stock assessment

2)2) Develop conceptual model of life historyDevelop conceptual model of life history

3)3) Describe food and feeding habits (food web model)Describe food and feeding habits (food web model)

4)4) Analyze age/size composition dataAnalyze age/size composition data

5)5) Explore historical bycatch for trends in abundanceExplore historical bycatch for trends in abundance

6)6) Investigate inter-lab variation in aging techniquesInvestigate inter-lab variation in aging techniques

Data CollectionData Collection

Size, sex and maturitySize, sex and maturity Reproductive InfoReproductive Info Stomach ContentsStomach Contents AgeAge BloodBlood

MeasurmentsMeasurments

Male MaturityMale Maturity

Female MaturityFemale Maturity

Female MaturityFemale Maturity

Reproductive InfoReproductive Info Timing of Timing of

reproductive eventsreproductive events Embryo size and Embryo size and

developmentdevelopment Sex of embryosSex of embryos

PregnancyPregnancy

Pregnancy TimelinePregnancy Timeline

Stomach ContentsStomach Contents

Gross ID in fieldGross ID in field Contents stored in Contents stored in

Formalin and Formalin and returned to lab for returned to lab for specific ID and sizes specific ID and sizes of food itemsof food items

Age and BloodAge and Blood

22ndnd Dorsal Spine for Dorsal Spine for agingaging

Blood for Blood for reproductive reproductive hormoneshormones

Survey MethodsSurvey Methods Sport FishingSport Fishing

Yakutat BayYakutat Bay Homer/Cook InletHomer/Cook Inlet

Longline Longline Cross SoundCross Sound Yakutat BayYakutat Bay NMFS Sablefish SurveyNMFS Sablefish Survey

OthersOthers ADF&G surveys in SE Alaska, Prince William ADF&G surveys in SE Alaska, Prince William

Sound, Cook InletSound, Cook Inlet NMFS biennial trawl surveyNMFS biennial trawl survey Various commercial bycatchVarious commercial bycatch

Sample LocationsSample Locations

Sport FishingSport Fishing

Halibut fishing techniquesHalibut fishing techniques Herring/Salmon BaitHerring/Salmon Bait Chum: dogfish scraps, herring, rockfish Chum: dogfish scraps, herring, rockfish

and salmon scraps and salmon scraps ~16% of total samples~16% of total samples

LonglineLongline

Sablefish fishing gearSablefish fishing gear Squid or Herring BaitSquid or Herring Bait ~84% of total samples~84% of total samples

Early Early ResultsResults

YearYearSampling Sampling LocationLocation Start DateStart Date TypeType MalesMales FemalesFemales StomachsStomachs BloodBlood SpinesSpines

20042004 Yakutat BayYakutat Bay 7/27/20047/27/2004 SportSport 2222 9393 4949 00 103103

20042004GOA Cordova-GOA Cordova-

KodiakKodiak 8/9/20048/9/2004 LLLL 5252 8585 4444 6868 137137

20052005 SE near SitkaSE near Sitka 2/16/20052/16/2005 LLLL 4949 142142 00 00 00

20052005 Cross SoundCross Sound 4/21/20054/21/2005 LLLL 11 1414 1111 1414 1414

20052005 Yakutat BayYakutat Bay 5/8/20055/8/2005 LLLL 1111 2323 3434 00 3434

20052005 Yakutat BayYakutat Bay 5/24/20055/24/2005 SportSport 00 1515 1515 1111 1515

20052005 Cook InletCook Inlet 6/25/20056/25/2005 SportSport 66 2525 2929 3131 3131

20052005 Yakutat BayYakutat Bay 6/27/20056/27/2005 LLLL 4141 9797 9595 9595 138138

20052005GOA Ketchikan-GOA Ketchikan-

CordovaCordova 7/9/20057/9/2005 LLLL 112112 204204 208208 180180 316316

TotalsTotals 294294 698698 485485 399399 788788

Sport vs. LonglineSport vs. LonglineSportSport LonglineLongline

Total # SamplesTotal # Samples 161, 16%161, 16% 831, 84%831, 84%

Males in SampleMales in Sample 28, 17%28, 17% 266, 32%266, 32%

Females in SampleFemales in Sample 133, 83%133, 83% 565, 68%565, 68%

Mature MalesMature Males 13, 87%13, 87% 124, 60%124, 60%

Mature FemalesMature Females 21, 23%21, 23% 66, 24%66, 24%

Pupping SeasonPupping Season 23 Pregnant females sampled23 Pregnant females sampled 223 total embryos223 total embryos Growth rates from Ketchen, 1972Growth rates from Ketchen, 1972

Pupping SeasonPupping Season 23 Pregnant females sampled23 Pregnant females sampled 223 total embryos223 total embryos Growth rates from Ketchen, 1972Growth rates from Ketchen, 1972

Estimated Pup "Birth" Month

0

10

20

30

40

50

60

1 2 3 4 5 6 7 8 9 10 11 12

Month

Frequency

FecundityFecundity

Total Fecundity as a Function of Length-Alaska

y = 0.3273x - 24.328

R2 = 0.4289

0

5

10

15

20

25

75 80 85 90 95 100 105 110 115 120 125

Female TLext (cm)

Number of pupsTotal Fecundity as a Function of Length-Puget

Soundy = 0.2389x - 17.207

R2 = 0.3735

02

4

6

8

10

1214

16

80 90 100 110 120

Female Tlext (cm)

Number of pups

Stomach ContentsStomach ContentsAll Stomachs

fish42%

cephalopods

4%

Shellfish

30%

shark0%

unk

14%

other

1%

roe

1%

offal3%

jellyfish

5%

n=489216 empty (44%)16 multple food types (14%)

Shellfish Breakdown

shrimp44%

krill33%

clam8%

other3%

crab12%

Fish Breakdown

flatfish3%

herring11%

unk fish78%

forage fish4%

salmon4%

Stomach ContentsStomach ContentsGulf

fish46%

shellfish32%

jelly1%

other1%

unk15%

cephalopod4%

roe

1%

n=308

137 empty (45%)

Bay

fish39%

shellfish

30%

jelly

10%

other2%

unk12%

shark

1%roe2%

cephalopod4%

n=22280 empty (36%)

Gulf BayGulf BayGulf Shellfish

krill53%

crab6%

shrimp39%

tanner crab2%

Gulf Fish

fish32%

roe1%

herring11%

salmon2%

forage fish2%

fish parts48%

flatfish4%

Bay Shellfish

shrimp52%

crab8%

krill3%

clam9%

razor clam9%

dungie3%

hermit8%

shellfishparts3%

snail5%

Bay Fish

fish45%

herring9%

salmon6%

offal14%

dogfish2%

forage fish3%

fish parts14%

rockfish2%

roe3%

flatfish2%

Future Sampling PlansFuture Sampling Plans 2006:2006:

Cordova, Copper River Cordova, Copper River Salmon bycatchSalmon bycatch

Homer/Cook Inlet sport Homer/Cook Inlet sport fishing and Ninilchik set fishing and Ninilchik set net fisherynet fishery

NMFS Sablefish surveyNMFS Sablefish survey ADF&G Kamishak Bay ADF&G Kamishak Bay

and Prince William Sound and Prince William Sound surveysurvey

Yakutat Bay, aerial and Yakutat Bay, aerial and trawltrawl

New sampling toys:New sampling toys:

Expected Project OutcomesExpected Project Outcomes Describe seasonal size and age Describe seasonal size and age

distributions, reproductive patternsdistributions, reproductive patterns Gain better understanding of dogfish feeding Gain better understanding of dogfish feeding

ecology and food web dynamicsecology and food web dynamics Estimate region specific stock assessment Estimate region specific stock assessment

parameters parameters Estimate GOA abundance from parameters Estimate GOA abundance from parameters Build inter-agency cooperationBuild inter-agency cooperation

Other dogfish projectsOther dogfish projects

Tagging study Tagging study Dean Courtney, NMFSDean Courtney, NMFS

$200 REWARD

For Electronic Tags in Spiny Dogfish

Dean Courtney National Marine Fisheries Service Auke Bay Laboratory 11305 Glacier Hwy Juneau, AK 99801 Call: 907 -789-6006 Fax: 907-789-6608 E-mail: dean.courtney@noaa.gov

Not to Scale

Other dogfish projectsOther dogfish projects

Stable Isotope/Feeding Ecology Stable Isotope/Feeding Ecology Alex Andrews, UAFAlex Andrews, UAF

Socioeconomics of a potential fisherySocioeconomics of a potential fishery Jason Gasper, UAFJason Gasper, UAF

Creel census and bycatch sampling with Creel census and bycatch sampling with ADF&GADF&G

Thanks!Thanks!

NPRBNPRB NMFS AFSCNMFS AFSC NMFS Auke Bay LabNMFS Auke Bay Lab

Dean Courtney, Chris Dean Courtney, Chris Lunsford, Brian VanWinkle, Lunsford, Brian VanWinkle, Dave Clausen, Mitch Dave Clausen, Mitch LorenzLorenz

ADF&GADF&G Willy Dunne, Ken Willy Dunne, Ken

Goldman, Bob Johnson, Goldman, Bob Johnson, Scott Meyer, Tory Scott Meyer, Tory O’Connell, Scott Pegau, O’Connell, Scott Pegau, Charlie Stock, Charlie Charlie Stock, Charlie Trowbridge, Mike Vaughn, Trowbridge, Mike Vaughn, Gordie Woods Gordie Woods

F/V Alaskan LeaderF/V Alaskan Leader F/V Kingfisher-Chris and F/V Kingfisher-Chris and

Natalie Ekstrom, Kyle Natalie Ekstrom, Kyle DickersonDickerson

F/V Sea View-John F/V Sea View-John EthridgeEthridge

F/V Winter King-Rex F/V Winter King-Rex Murphy, Holly VanPelt, Murphy, Holly VanPelt, MikeyMikey

F/V Ocean ProwlerF/V Ocean Prowler