Covariation between North Pacific climate and auklet demographic parameters at three western Aleutian islands during 1990-2008

Ian L. JonesBiology Department, Memorial University of Newfoundland

Due to their low trophic level, planktivorous seabirds’ demography might rapidly reflect changes in ocean productivity and zooplankton abundance

Objective

Measure auklet survival, productivity and chick diet at three western Aleutian Islands to look for effects of changing climate and oceanography, inferred from covariance across species, islands and years

Auklets (Auks, Alcidae Aethiini genus Aethia)Long-lived planktivorous monogamous colonial seabirds

Least Auklet Crested Auklet Whiskered Auklet

SmallestEats copepodsMigratory, disperseswidely in winter

LargestEats euphausiidsMigratory, localizedin winter

IntermediateMixed dietResidentAleutians only

Predictions

If auklet demography is regulated by very large scale climate processes

then

Survival, productivity, diet should correlate among:auklet speciesdifferent island colony sites

and with climate covariates

Scale effects

Survival - largest scale - measured on an annual basis, birds widely dispersed in North Pacific

Productivity - more local scale, reflects conditions near colony site, during breeding season only

Chick diet - during chick rearing (July) only

product of a collaboration

Co-investigatorsVernon Byrd, Jeff Williams, Art Sowls -Alaska Maritime NWRAlex Bond, Heather Major - grad students

FieldworkersG. Beyersdorf, K. Brenneman, J. Citta, T. Clarke, L. Cowen, A. Durand, E. Drew, B. Drummond, J. Fisher, G. Fraser, M. Grinnell, M. Hipfner, S. Hootman, A. Hunt, N. Jones, T. Joyce, P. Kappes, H. Knechtel, N. Konyukhov, S. Lantz, G. Loh, S. Lorenz, H. Major, J. Marais, G. McClelland, L. Meehan, M. Murphy, A. Nunez de la Mora, M. Ortwerth, A. Palmer, L. Parker, J. Pennell, M. Renner, H. Renner, D. Roby, N. Rojek, L. Scharf, K. Shea, E. Sommer, G. Spencer, J. Sutton, I. Stevenson, G. Thomson, A. Veit, N. Winter, J. Wade, V. Zubakin et al.

DiscussionsJohn Piatt, Dan Roby, Sasha Kitaysky et al.

Three study islands

1990-2008 (19)

2001-2008 (8)

1996-2007 (12)

400 nm

BuldirKiska

Kasatochi

Pitfalls

Land-based predators (rats and gulls)

Arduous capture-mark-recapture

Replication not

Climate covariates

NPI: sea level pressure over 30N-65N, 160E-140W

ALPI: area with pressure <100.5 kPa, anomaly from meanPDO: PC1 of North Pacific monthly SST

NPI: sea level pressure over 30N-65N, 160E-140W

ALPI: area with pressure <100.5 kPa, anomaly from meanPDO: PC1 of North Pacific monthly SST

NPI: sea level air pressure over 30N-65N, 160E-140WALPI: area with air pressure <100.5 kPaPDO: PC1 of North Pacific monthly SST

When pressure is low and Aleutian Low is big, North Pacific near Aleutians is cool and churned up (MORE PRODUCTIVE) but also STORMIER

Main TalusLeAu & CrAu1990-2008

Crested PointWhAu1992-2008

Buldir

Kiska

Sirius PointLeAu & CrAu1996-2008

Kasatochi

Thundering TalusLeAu & CrAu1996-2007

Kasatochi

October 2009Jerry Morris photo

Kasatochi

September 2009

Chris Waythomas photo

SurvivalConcordance across islands - Least Auklet

SurvivalConcordance across islands - Crested Auklet

Survival Concordance between species

0.6

0.7

0.8

0.9

1

0.6 0.7 0.8 0.9 1LeAu survival

CrAu survival

NOT

SurvivalClimate covariates - Least Auklet

SurvivalClimate covariates - Crested Auklet

Productivity

Poorly correlated between species and islands

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1990199119921993199419951996199719981999200020012002200320042005200620072008

CrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAuCrAu

Buldir

Kasatochi

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1990199119921993199419951996199719981999200020012002200320042005200620072008

LeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAuLeAu

Buldir

Kasatochi

Least Auklet

Crested Auklet

Pro

du

ctiv

ity

Year

Productivity vs Climate covariates

ALPI - when Aleutian lowis large, productivity is decreased

Phenology vs SST

Jeff Williams

Chick Diet

Year1994 2006

CrestedAuklet

LeastAuklet

varies across years, evidence of concordance, different auklet species feed their chicks different prey taxaNeocalanus plumchrus

Euphausiid

Neocalanus cristatus

Chick Diet

Year1994 2006

LeastAuklet

Kasatochivaries between islands

Neocalanus plumchrus

Euphausiid

Neocalanus cristatus

LeastAuklet

Buldir

Conclusions (tentative)

Least and Crested Auklet survival was correlated across islands 400 nm apart during 1996-2007

Survival seems to vary with large-scale climate indices in all three auklet species, ALPI

Productivity was less correlated among islands and species, but seems to vary with large-scale climate indices in all three auklet species, ALPI

Future analyses will focus on comparison of patterns of all of survival, productivity and diet across islands and auklet species

North Pacific Research Board

United States Fish and Wildlife ServiceAlaska Maritime National Wildlife Refuge

Natural Sciences and Engineering Research Council of Canada Memorial University of Newfoundland

Indian and Northern Affairs Canada Northern Scientific Training Program

Funding acknowledgements