International research teams have studied the breeding biology of little
auks (Alle alle) and kittiwakes (Rissa tridactyla) in Svalbard
over the last five decades. Now Børge Moe (Norwegian Institute for Nature
Research, NINA) and his team compared changes of reproductive pattern in
these two species with changes in climate during this period.
The timing of breeding is a life-history trait that can greatly affect
fitness, because successful reproduction depends on the match between the
food requirements for raising young and the seasonal peak in food
availability. 343
The researchers therefore compared the development of hatch dates of two
seabird species, little auks and kittiwakes, with several climate
parameters. Their investigation were based on datasets from Hornsund for the
period 1963-2008 (little auks) and from Kongsfjord for the period 1970-2008
(kittiwakes).
The study shows that spring climate on the West Coast of Svalbard has
changed considerably during the last 50 years, with a strong increase in
both air temperature (TEMP) and sea surface temperature (SST) and a decrease
in sea ice concentration.
Earlier breeding in little auks
In the same period, little auks showed a trend for earlier breeding and
spring air temperature was the best predictor of little auk phenology, i.e.
little auks hatched earlier with higher air temperature.
Temperature generally governs the timing of snow melt, which plays an
important role for nest site availability for the ground-nesting little auks.
Lower breeding success in kittiwakes
Kittiwakes showed a non-significant trend for later breeding and spring sea
surface temperature was the strongest predictor of kittiwake phenology.
In years with a late breeding start, kittiwakes laid less eggs and had
generally a lower breeding success (Fig. 2). This may indicate low parental
investment as a result of poor food availability. Food availability for
kittiwakes is depending on the development of the polar marine food web,
which again is dependend on several climatic factors.Variable
responses
The study demonstrates that the two seabird species respond differently to
changes in climate parameters and that single parameters affect the species
with different strength.
It is a concern that different parts of the food web may react differently
to changes in climate, both in terms of speed and direction. This may result
in seabirds breeding too early or too late compared to the peak of food
availability in the marine environment. Such a mis-match would result in a
reproductive failure.
In this study no such mis-match could be shown, but in combination with
additional studies on the timing of the marine food web, it will give
valuable answers.
Research groups from Poland, USA, Norway and France have been contributing
to these data over several decades and the current study is based on the
work of researchers during the entire period. Parts of the study have been
supported by the Arctic Field Grant from SSF.
(Source: Børge Moe, NINA)
Contact: Børge Moe
Read more:
Moe B, Stempniewicz L, Jakubas D, Angelier F, Chastel O, Dinessen F,
Gabrielsen GW, Hanssen F, Karnovsky NJ, Rønning B, Welcker J,
Wojczulanis-Jakubas K, Bech C (2009) Climate change and phenological
responses of two seabird species breeding in the high-Arctic. Mar Ecol Prog
Ser 393: 235–246
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Little auk (Photo: C. Hübner)
Kittiwake (Photo: C. Hübner)
Figure taken from Mar Ecol Prog Ser 393, p 240.
Figure taken from Mar Ecol Prog Ser 393, p 241.
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