Spring Stopover of Birds on the Laptev Sea Polynya
D.V. Solovieva
Lena-Delta State Reserve. 28 Fiodorova St .. 678400 Tiksi. Yakutia. Russia
Received 3 March 1997 and accepted in revised form 9 February 1998
Abstract - Four species of marine birds were found to occur in spring-time on the Laptev
Sea Polynya. All birds were observed migrating westward above ice-free waters and drift ice
fields. Inspection of King Eider (Somateria spectabilis) bioenergetics on the Polynya
shows that this species daily pays 3.17 BMR in males and 3.44 BMR in females for the
occurring here. Eider's impact on bottom fauna is 0.10-0.17% of biomass.
Introduction
The first suggestions that Great Siberian Polynya (Figure I) is inhabited by birds came from the
very beginning of the century. The early spring migration of "dark" ducks over Chukchi Sea
fast ice was noted by the Zarya expedition (Birulya, 1907). The information from weather
stations' staff, as well as the fact that some species do migrate from sea to land in springtime
when arriving at the breeding grounds, generally supported this idea. The Transdrift IV
expedition at the Laptev Sea Polynya (Figure 1) enabled to obtain the data on bird fauna and
abundance here. Surveys, being conducted in one week at the moment of intensive spring
migration, don't allow to understand either birds stay on the Polynya for a long time, or they
use it only as a fly-way, providing stopover for the rest and feeding. Periods and purposes for
why birds visit Polynya are still under discussion: from our point of view, the food sources of
the bottom and the ice-free water of polynya, not used by birds during the entire winter,
provide good conditions for overspringing of many marine birds. Ducks were noted to appear
offshore the New-Siberian Islands already in April (Rakhimov, pers. com.).
Is it difficult for birds to survive in low ambient temperatures aggravating by unstable ice
conditions? We try to answer by the estimation of daily energy budget (DEB) in birds and their
impact on the fauna of invertebrates in the Polynya. We use one species - the King Eider
(Somateria spectabilis) - for these proposes because additional data to calculate it's DEB are
available. Complete picture of bird community existence on the Polynya is a subject for the
future investigations.
Methods
Aerial surveys and observation of migration
We surveyed the Laptev Sea Polynya adjacent to the Lena-Delta on 25, 27, and 29 of May
1996. Helicopter surveys were conducted from an altitude of 100m at 180 kmlhr. Transect
width was 250m on one side of MI-8 helicopter. A tape recorder was used to note all birds
observations. Total area of the Polynya was estimated from the ice-map. As all birds were
found to use the ice-free parts of Polynya only, the ice-free area was taking into account to
estimate bird abundance (Figure 2). Spring bird migration was registered from the edge of both
fast and drifting pack ice. Totally we spent six hours observing migration on 25 and 29 of May.
In: Kassens. H .. H.A. Bauch, l. Dmitrenko, H. Eicken, H.-W. Hubberten, M. Melles, J. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin. 1999. 189-195.
D.V. Solovieva
Lena-Delta State Reserve. 28 Fiodorova St .. 678400 Tiksi. Yakutia. Russia
Received 3 March 1997 and accepted in revised form 9 February 1998
Abstract - Four species of marine birds were found to occur in spring-time on the Laptev
Sea Polynya. All birds were observed migrating westward above ice-free waters and drift ice
fields. Inspection of King Eider (Somateria spectabilis) bioenergetics on the Polynya
shows that this species daily pays 3.17 BMR in males and 3.44 BMR in females for the
occurring here. Eider's impact on bottom fauna is 0.10-0.17% of biomass.
Introduction
The first suggestions that Great Siberian Polynya (Figure I) is inhabited by birds came from the
very beginning of the century. The early spring migration of "dark" ducks over Chukchi Sea
fast ice was noted by the Zarya expedition (Birulya, 1907). The information from weather
stations' staff, as well as the fact that some species do migrate from sea to land in springtime
when arriving at the breeding grounds, generally supported this idea. The Transdrift IV
expedition at the Laptev Sea Polynya (Figure 1) enabled to obtain the data on bird fauna and
abundance here. Surveys, being conducted in one week at the moment of intensive spring
migration, don't allow to understand either birds stay on the Polynya for a long time, or they
use it only as a fly-way, providing stopover for the rest and feeding. Periods and purposes for
why birds visit Polynya are still under discussion: from our point of view, the food sources of
the bottom and the ice-free water of polynya, not used by birds during the entire winter,
provide good conditions for overspringing of many marine birds. Ducks were noted to appear
offshore the New-Siberian Islands already in April (Rakhimov, pers. com.).
Is it difficult for birds to survive in low ambient temperatures aggravating by unstable ice
conditions? We try to answer by the estimation of daily energy budget (DEB) in birds and their
impact on the fauna of invertebrates in the Polynya. We use one species - the King Eider
(Somateria spectabilis) - for these proposes because additional data to calculate it's DEB are
available. Complete picture of bird community existence on the Polynya is a subject for the
future investigations.
Methods
Aerial surveys and observation of migration
We surveyed the Laptev Sea Polynya adjacent to the Lena-Delta on 25, 27, and 29 of May
1996. Helicopter surveys were conducted from an altitude of 100m at 180 kmlhr. Transect
width was 250m on one side of MI-8 helicopter. A tape recorder was used to note all birds
observations. Total area of the Polynya was estimated from the ice-map. As all birds were
found to use the ice-free parts of Polynya only, the ice-free area was taking into account to
estimate bird abundance (Figure 2). Spring bird migration was registered from the edge of both
fast and drifting pack ice. Totally we spent six hours observing migration on 25 and 29 of May.
In: Kassens. H .. H.A. Bauch, l. Dmitrenko, H. Eicken, H.-W. Hubberten, M. Melles, J. Thiede and L. Timokhov (eds.)
Land-Ocean Systems in the Siberian Arctic: Dynamics and History. Springer-Verlag, Berlin. 1999. 189-195.