Reproductive responses of planktivorous and piscivorous to climate variability in the northern

Alexander Kitaysky1 & Elena Golubova2

1Institute of Arctic Biology University of Fairbanks, U.S.A. 2Institute of Biological Problems of the North Magadan, Russia Inter-annual oceanographic change

Seabird reproductive performance

Causal links between reproduction and climate variability on small and large geographic scales

Change in diet composition: over time and in relation to climate variability Bering Sea (1960s-1990s)

• decline in populations of piscivorous seabirds Springer 1992 Hunt & Byrd 2000

• increase in populations of planktivorous seabirds Piatt et al. 1990 Konyoukhov 1991 Sea surface temperature in the Bering Sea 1.5

planktivorous increased 1.0 WARM phase piscivorous declined C) o 0.5

0.0

-0.5

SST ANOMALY ( ANOMALY SST -1.0

COLD phase -1.5 1957 1962 1967 1972 1977 1982 1987 1992

YEAR Study area: Talan Island 1987-2001

Longitude (degrees East) 148 149 150 151 152 60 Kitaysky & Golubova 2000;

o & in preparation 10-14 C

s

r

e

t Cold-core eddy

a

Talan I. w

l

a

t Talan I.

s

a

59 o C Sea of Okhotsk

Latitude (degrees North) Latitude (degrees 1987-2003 o Tauyskaya Bay o C 10-14 C 5-8 Kuril current Jamskoe current 58

Siberia y a B v o Study hypothesis: Tauyskaya Bay h k li e h S

a environmental change causes

k t

a

h

c

m a contrasting trends in Sea of Okhotsk K reproductive performance of

s planktivorous and piscivorous d n la Is ril u K alcids Tufted 1.00 Horned puffin Parakeet auklet Crested auklet 0.75

0.50

0.25

Reproductive success no data 0.00 1986 1987 1988 1989 1990 1991 1992 1993 1994 11.5

C o

10.5

o 9.5 long-term SST = 9.3

8.5

SST (July 1 - August 30) SST (July 1 - August 7.5 1986 1987 1988 1989 1990 1991 1992 1993 1994 Year Sea-Surface Temperature 1.00 Horned puffin Parakeet auklet Crested auklet 0.75 “WARM” PHASE “COLD” PHASE 0.50

0.25

Reproductive success no data 0.00 1986 1987 1988 1989 1990 1991 1992 1993 1994 11.5

C o

10.5

o 9.5 long-term SST = 9.3

8.5

SST (July 1 - August 30) SST (July 1 - August 7.5 1986 1987 1988 1989 1990 1991 1992 1993 1994 Year Dates of permanent ice disappearance

2.0

1991 1.5 1994

1.0 1989

C) 1990 o

0.5 “WARM” PHASE 0.0 “COLD” PHASE -0.5 1987 -1.0 July -- August SST anomaly ( 1988 1992 -1.5 1993

-2.0 0May 1 May 10203040 10 May 20 May 30 June 10 Date 100 Kitaysky & Golubova 2000 Talan I. 80 Sea of Okhotsk 1987-1994

60

40

20 Planktivorous auklets Reproductive success (%) Reproductive Piscivorous 0 COLD WARM OCEANOGRAPHIC REGIME Distribution of adult euphausiids Thysanoessa rashii (major prey of planktivorous auklets)

“COLD” regime

“WARM” regime Distribution of Acartia and calanoid copepods (major prey of small “forage” fish)

“COLD” regime

“WARM” regime Talan I. 1987-2001 planktivorous: piscivorous: Tufted puffins Crested auklets Black-legged kittiwakes ) 80 80

40 40

0 0

-40 -40

-80 -80 -2 -1 0 1 2 -2 -1 0 1 2 Reproductive success Reproductive deviation from long-term mean deviation from (

Sea-surface temperature ANOMALY (oC) Conclusion: Environmental change affects trophic level linkages in marine ecosystems

• Alternations in distribution of zooplankton are driven by local inter-annual oceanographic change

• Reproductive performance of planktivorous and piscivorous seabirds reflects these changes Arctic Oscillation Index

Is reproduction of in the northern Sea of Okhotsk related to climate variability on a large geographic scale? Talan SST vs composite indices of climate in the North Pacific 1986-2003 PDO NPI AO annual Jan-April annual mean mean mean

Talan I. r=+0.78 r=+0.53 r=-0.54 SST P<0.001 P<0.04 P<0.04 August Talan I. 1987-2003 Talan I. 1987-2003 Talan I. 1987-2003 Conclusion: Environmental change affects trophic level linkages in marine ecosystems

• Alternations in reproduction of piscivorous and planktivorous seabirds in the northern Sea of Okhotsk are driven by inter-annual oceanographic change on large geographic scale Arctic Oscillation Index

Are DIETs of birds in the northern Sea of Okhotsk related to changes in climate phenomena on a large geographic scale? Diet composition of puffin chicks on Talan I. 1987-2003 Fish

Horned 29 spp 6 spp Puffin 99% biomass 1% biomass N=6 years

Tufted 37 spp 7 spp Puffin 98% biomass 2% biomass N=9 years Talan I. 1987-2003

Change in diet composition, SANDLANCE 1987-2003 100

80

60

40 % BIOMASS, wet

20

Horned puffin 0 1988 1992 1996 2000 2004 Tufted puffin YEAR Talan I. 1987-2003

Change in diet composition, Tufted puffin, 1987-2003 100

80

60

40 % BIOMASS, wet 20

HERRING 0 1988 1992 1996 2000 2004 YEAR Talan I.

1987-2003 Change in diet composition, Tufted puffin, 1987-2003 5

Pacific lamprey

4

3

2 %BIOMASS, wet

1

0

1988 1992 1996 2000 2004 YEAR Talan I. 1987-2003

Change in diet composition, Tufted puffin, 1987-2003 70

60

50

40

30 %BIOMASS, wet 20

10 Age 1+ Saffron cod 0 Age 0+ 1988 1992 1996 2000 2004 Walleye Pollock YEAR Arctic Oscillation Index

Are DIETs of birds in the northern Sea of Okhotsk related to climate variability on a large geographic scale? Diet (% biomass) vs composite indices of climate in the North Pacific 1986-2003 PDO NPI AO annual Jan-April annual mean mean mean Horned r=+0.91 r=-0.74 r=-0.95 Puffin P<0.011 P=0.090 P<0.01 N=6 gadids gadids pollock r=+0.66 r=-0.60 Tufted P=0.055 P=0.088 Puffin Saffron Saffron N=9 cod cod Diet (% biomass) vs reproductive performance of puffins on Talan I. 1986-2003

Pollock Flatfish Poachers

Repr. success r=-0.80 r=-0.89 r=-0.97 r=-0.94 Horned P=0.057 P<0.02 P<0.01 P<0.01 Puffin N=6 years Summary 1. Local oceanographic conditions in the northern Sea of Okhotsk are driven by large-scale oceanographic patterns 2. Availability of forage fish and consequently reproduction are determined by these patterns 3. The same oceanographic event has opposite consequences for planktivorous and piscivorous birds 4. Whether these relationships are specific to the Sea of Okhotsk or apply to other arctic regions remains to be seen •Thanks to: – A. Andreev, J.F. Piatt, and all the Russian and American colleagues and students who participate in this ongoing project

•Funding: – Russian (Soviet) Academy of Sciences – Institute of Biological Problems of the North (Magadan) –EVOS –NPRB – Institute of Arctic Biology, UAF