Foraging patterns of Northern Foraging patterns of Northern Fulmars (Fulmars (Fulmarus glacialisFulmarus glacialis) in ) in Alaska inferred from fatty acid Alaska inferred from fatty acid

signature analysissignature analysis

Shiway W. Shiway W. WangWangUniversity of Alaska University of Alaska Fairbanks USGS, Alaska Fairbanks USGS, Alaska Science CenterScience Center

Sara J. IversonSara J. IversonDalhousie University, Dalhousie University, CanadaCanada

Alan M. Alan M. SpringerSpringerUniversity of Alaska University of Alaska FairbanksFairbanks

Scott A. HatchScott A. HatchUSGS, Alaska Science USGS, Alaska Science CenterCenter

GoalGoal

Describe foraging characteristics and Describe foraging characteristics and diet of Northern Fulmarsdiet of Northern Fulmars

Assess trophic pathways of marine Assess trophic pathways of marine ecoregions in Alaskaecoregions in Alaska

Why fulmars?Why fulmars?

opportunistic, generalist predators

major colonies located in distinct ecoregions

largest component of seabird bycatch in AK

are they sensitive to ecosystem change?

Pribilofs Pribilofs (outer shelf-shelf (outer shelf-shelf

break)break)80,000 birds80,000 birds

no obvious trendno obvious trend

Chagulak Chagulak (Aleutian (Aleutian

Archipelago)Archipelago)½ million birds½ million birds

popn trend unknownpopn trend unknown

Semidis Semidis (Alaska Coastal (Alaska Coastal

Current)Current)440,000 birds440,000 birdspopn stablepopn stable

St.Matthew- St.Matthew- Hall Hall (middle shelf)(middle shelf)

450,000 birds450,000 birdspopn trend unknownpopn trend unknown

Why fatty acids?Why fatty acids? foraging patterns, diets foraging patterns, diets

of marine mammals and of marine mammals and seabirdsseabirds

non-lethal, less invasive non-lethal, less invasive

diet over time vs. last diet over time vs. last mealmeal

FA carbon chain length ≥ FA carbon chain length ≥ 14 pass into tissues 14 pass into tissues relatively intactrelatively intact

FA signatures conserved FA signatures conserved through the food chain, through the food chain, act as indicators of dietact as indicators of diet

To compare the adipose tissue To compare the adipose tissue FA signatures of adult fulmars FA signatures of adult fulmars

1.1.among coloniesamong colonies

2.2.between years within between years within coloniescolonies

3.3.between seasons within between seasons within coloniescolonies

ObjectiveObjective

Adipose tissue fatty acids will varyAdipose tissue fatty acids will vary

1.1. among colonies among colonies - located in distinct oceanographic habitats- located in distinct oceanographic habitats

2.2. between years within colonies between years within colonies - response of prey popn to inter-- response of prey popn to inter-annual environmental changesannual environmental changes

3.3. between seasons within colonies between seasons within colonies - life history traits of prey- life history traits of prey

PredictionsPredictions

St. GeorgeSt. George

ChagulakChagulak

ChowieChowiett

MayMay

2003 n = 30 2003 n = 30 2004 n = 252004 n = 25

AugustAugust

2003 n = 27 2003 n = 27 2004 n = 312004 n = 31

JuneJune

2003 n = 29 2003 n = 29 2004 n = 302004 n = 30

AugustAugust

2003 n = 9 2003 n = 9 2004 n = 262004 n = 26

JulyJuly

2004 n = 302004 n = 30

Storage: glass vials Storage: glass vials with Teflon-lined caps with Teflon-lined caps w/chloroform + 0.01% w/chloroform + 0.01%

BHT (antioxidant)BHT (antioxidant)

NoosepoNoosepolele

dip netdip net

adipose adipose tissuetissue

Lab AnalysisLab Analysis

lipid extractionlipid extraction

transesterification to transesterification to fatty acid methyl fatty acid methyl estersesters

gas chromatographygas chromatography (e.g. Iverson et al. 1997)

Diets differed among Diets differed among coloniescolonies

1st discriminant function

- 4 - 2 0 2 4

2nd

dis

crim

inan

t fu

ncti

on

- 4

- 2

0

2

4

St. GeorgeChowiet

Chagulak

Means ± SE Means ± SE 1st 6 functions (p < 0.0001), 69% of the variation, 76% correctly classified

Diets differed among Diets differed among coloniescolonies

Diets differed somewhat in May Diets differed somewhat in May between years for Chowietbetween years for Chowiet

1st discriminant function

- 4 - 2 0 2 4

2nd

dis

crim

inan

t fu

ncti

on

- 4

- 2

0

2

4

Means ± SE Means ± SE

May 04May 04

May 03May 03

Diets differed somewhat in May Diets differed somewhat in May between years for Chowietbetween years for Chowiet

ChowieChowiett

1st discriminant function

- 4 - 2 0 2 4

2nd

dis

crim

inan

t fu

ncti

on

- 4

- 2

0

2

4

May 04May 04

May 03May 03

ChowieChowiett

Means ± SE Means ± SE

Diets similar in Aug between Diets similar in Aug between years for Chowietyears for Chowiet

Aug 03Aug 03 Aug 04Aug 04

1st discriminant function

- 4 - 2 0 2 4

2nd

dis

crim

inan

t fu

ncti

on

- 4

- 2

0

2

4

May 04May 04

May 03May 03

ChowietChowiet

Aug 03Aug 03

Means ± SE Means ± SE

Diets same in June between years Diets same in June between years for St. Georgefor St. George

Jun 03Jun 03

Jun 04Jun 04

Tukey’s: 1 Tukey’s: 1 FA (p < FA (p < 0.003)0.003)

St. GeorgeSt. George

Aug 04Aug 04

1st discriminant function

- 4 - 2 0 2 4

2nd

dis

crim

inan

t fu

ncti

on

- 4

- 2

0

2

4ChowietChowiet

Means ± SE Means ± SE

Diets differed between Diets differed between seasonsseasons

May 03, 0403, 04

Aug 03, 0403, 04

St. GeorgeSt. George

Jun 03, 04 03, 04

ChowietChowiet

ChagulakChagulakJuly 0404

St. GeorgeSt. GeorgeAug 0404

EARLIER

LATER

SummarySummary1.1. Differences in FA signatures Differences in FA signatures

among coloniesamong colonies difference in food web structuresdifference in food web structures

2.2. Little difference in FA signatures Little difference in FA signatures between years within coloniesbetween years within colonies

similar diets and food web pathways similar diets and food web pathways between yearsbetween years

3.3. Differences in FA signatures Differences in FA signatures between seasons within coloniesbetween seasons within colonies

seasonal variability in diets or in food web seasonal variability in diets or in food web pathwayspathways

What are What are fulmarsfulmars eatingeating??

Quantitative Fatty Acid Quantitative Fatty Acid Signature AnalysisSignature Analysis

(QFASA)(QFASA)

Iverson, Field, Bowen & Blanchard (2004) Ecological MonographsIverson, Field, Bowen & Blanchard (2004) Ecological Monographs

Iverson, Field, Bowen & Blanchard (2004) Ecological MonographsIverson, Field, Bowen & Blanchard (2004) Ecological Monographs

Principles of QFASA:Principles of QFASA:1. Marine fishes & invertebrates have characteristic1. Marine fishes & invertebrates have characteristic FA signaturesFA signatures

PC1

- 8 - 6 - 4 - 2 0 2 4 6 8

PC2

- 4

- 3

- 2

- 1

0

1

2

3

4

P. sandfish

SandlanceW. pollockP. jordaniP. pacifica

R. pacifica

C. Melanaster

P. cod

B. milleriN. smoothtongue

L. opalescens

D. theta

Eulachon

P. herring

B. magisterCapelin

T. spiniferaN. lampfish

Zooplankton

P. alberti

Western GOAWestern GOA

Iverson, Field, Bowen & Blanchard (2004) Ecological MonographsIverson, Field, Bowen & Blanchard (2004) Ecological Monographs

1. Marine fishes & invertebrates have characteristic1. Marine fishes & invertebrates have characteristic FA signaturesFA signatures

2. These signatures are deposited in predators 2. These signatures are deposited in predators in a predictable wayin a predictable way

3. Calculate what mix of prey signatures comes 3. Calculate what mix of prey signatures comes closest to matching that of a given predatorclosest to matching that of a given predator

Principles of QFASA:Principles of QFASA:

Validation of QFASA

Validation of QFASA

Common MurreCommon Murre

Red-legged Red-legged KittiwakeKittiwake

QFASA Model: ProceduresQFASA Model: Procedures

4. Calculate shortest statistical 4. Calculate shortest statistical distance between real bird and our distance between real bird and our estimate of that birdestimate of that bird

1. Average (or series of averages) of prey1. Average (or series of averages) of prey signatures signatures

2. Apply calibration coefficients to predator to 2. Apply calibration coefficients to predator to account for metabolism of specific FAs account for metabolism of specific FAs

3. What mix of those prey signatures3. What mix of those prey signatures comes closest to a given (calibrated) bird?comes closest to a given (calibrated) bird?

jellyfishjellyfishP.codP.cod

shrimpshrimpsandfishsandfish

sandlancesandlanceamphipodsamphipods

eulachoneulachonn.lampfishn.lampfish

n.sm.tonguen.sm.tonguemyctophidaemyctophidae

pollockpollockzoopzoop

0.5

0.4

0.3

0.2

0.1

0

% ofdiet

Chowiet (Semidi Is)Chagulak (Aleutians)St. George (Pribilofs)

Preliminary QFASA Preliminary QFASA Estimates of Fulmar DietsEstimates of Fulmar Diets

ConclusionConclusion

Fatty acid signature analysis is a powerful Fatty acid signature analysis is a powerful tool in comparing and describing the tool in comparing and describing the diets of fulmars and other predators, diets of fulmars and other predators,

and will provide additional insight into and will provide additional insight into the structure and variability of marine the structure and variability of marine

food webs in Alaska.food webs in Alaska.

FUNDINGFUNDING

USGS-SCEP, AK Science USGS-SCEP, AK Science Center Center

NPRB/ReFERNPRB/ReFERDalhousie UniversityDalhousie University

Logistical SupportLogistical Support

Alaska Maritime NWR/USFWS Alaska Maritime NWR/USFWS

M/V Tiglax, F/V Big Valley M/V Tiglax, F/V Big Valley

USCG Kodiak Air StationUSCG Kodiak Air Station

photos: S.Wang, C.Warbelow, M.Shultz, V.Gillphotos: S.Wang, C.Warbelow, M.Shultz, V.Gill

Field WorkField Work

A.Larned, E.Naughter, M.Nielson, A.Larned, E.Naughter, M.Nielson, N.Bargmann, A.Ramey, D.Mulcahy, N.Bargmann, A.Ramey, D.Mulcahy,

T.KitayskyT.Kitaysky

Thanks!Thanks!Lab Analysis & EquipmentLab Analysis & Equipment

S.Lang & S.Temple (Dalhousie) S.Lang & S.Temple (Dalhousie) S.Henrichs, C. Stark (UAF)S.Henrichs, C. Stark (UAF)

Suggestions & SupportSuggestions & Support

UAF/Dalhousie Grad StudentsUAF/Dalhousie Grad Students

Additional Committee MembersAdditional Committee Members

Loren Buck (SFOS/UAF) Loren Buck (SFOS/UAF)

Sasha Kitaysky (IAB/UAF)Sasha Kitaysky (IAB/UAF)

Prey CollectionPrey Collection

E.Chilton, A.Abookire, D.McKelvey, M.Wilkins, K.Williams, M.Wilson E.Chilton, A.Abookire, D.McKelvey, M.Wilkins, K.Williams, M.Wilson (NOAA/NMFS)(NOAA/NMFS)

B.Holladay & B.Norcross (UAF)B.Holladay & B.Norcross (UAF)

T.Kline (PWSSC)T.Kline (PWSSC)

Would you Would you like fries like fries with your with your kittiwake?kittiwake?

Will work for money… or Will work for money… or food..food..