Distribution of seabirds and marine mammals

Distribution and abundance of marine mammals and seabirds change continuously, but quantitative information on at-sea distribution is scarce. Climate change can lead to structural changes in distribution of species: a northward expansion of harbour porpoise distribution is hypothesized. During SEES we will collect quantitative data on the distribution and abundance of seabirds and marine mammals in Svalbard waters by conducting a ship-based visual survey, and collect passive acoustic monitoring data to detect presence of Harbour Porpoises in Svalbard waters.

Northwards currents transport plastic and other anthropogenic litter from more industrialized regions in the North Atlantic towards the Arctic. If available, biological samples such as deceased seabirds or faeces from seabird colonies or Arctic foxes are collected and analysed for potential plastic uptake.

The survey will be conducted from the bow, where a bird observation box will be fixed. An opportunistic line-transect survey is conducted when the ship sails with ca 10 knots on a predictable course (such as during transit). All birds, marine mammals and particular floating matter (balloons and fishing vessels) are logged at one side of the ship. To this end, one survey team of two or three observers detect, identify and count these objects within a strip of 300 m wide. Standardized counting methods from the European Seabirds At Sea (Tasker et al. 1984) are used. The behaviour of observed animals is noted according to Camphuysen & Garthe (2004). GPS positions and environmental conditions are recorded. Whenever possible observations are made during other activities, these are recorded as off-effort observations.