Aarhus Universitets segl

No. 337: Population size and habitat use of breeding seabirds in Northeast Greenland

Frederiksen, M., Mosbech, A., Andersson, A., Castro, A.C., Egevang, C., Fort, J., Grémillet, D., Linnebjerg, J.F., Lyngs, P. Nielsen, H.H. & Rømer, J.K. 2019. Population size and habitat use of breeding seabirds in Northeast Greenland. Field studies 2017-18. Aarhus University, DCE – Danish Centre for Environment and Energy, 48 pp. Scientific Report No. 337. http://dce2.au.dk/pub/SR337.pdf

Summary

As part of the Northeast Greenland Environmental Study Program, various colony-based studies of seabirds were carried out in 2017 and 2018, with the aim of identifying important areas during the breeding season. Logistical challenges led to not all planned studies being completed. The following studies were completed:

In 2017, GPS tracking of Sabine’s gulls took place at Henrik Krøyer Holme at the Northeast Water polynya. Because of heavy nest predation from Arctic foxes, the amount of data collected was limited, and only the egg-laying period was covered. The Sabine’s gulls foraged along the ice edge north and south of the colony, at distances up to 30-40 km.

In 2018, GPS tracking of ivory gulls took place at Station Nord and a newly discovered colony 18 km from there. Unfortunately, it was not possible to track ivory gulls at Henrik Krøyer Holme, and the tracked birds only used the Northeast Water polynya, and the Greenland Sea in general, to a very limited extent. Instead, they foraged in the Wandel Sea north of Nordostrundingen. We obtained good data from 10 birds over a period up to one month, during which time they completed a total of 292 foraging trips covering more than 41,000 km. Three types of foraging trips could be identified, and these types can probably be generalised to the Greenland Sea:

  • Long trips of up to several thousand km into the pack ice, where the birds spend much time searching for presumed rich food sources, which might be seal carcasses.
  • Shorter, repeated trips to the nearest areas of ice-free sea, where the birds presumably search for fish and crustaceans.
  • Specific individuals made numerous trips to the calving glacier Marsk Stig Bræ, where they presumably foraged on crustaceans killed by osmotic chock when salt water and meltwater mix.
  • In addition, all tracked individuals spent time at Station Nord, where they foraged at the kitchen. However, this activity did not take up much of their daily time budget.

In 2018, field work was carried out in the little auk colony at Kap Høegh. Here, an automatic monitoring video camera and a time-lapse camera were installed, which in combination with GPS tracking and other studies carried out in the colony by collaborators from the French National Centre for Scientific Research (CNRS) will provide important data on the little auks’ use of the Greenland Sea.

The planned air-based survey of ivory gull colonies in East Greenland was carried out in 2019, and results will be reported elsewhere.