Large variation occurs in the seabirds’ use of habitat throughout the year. Studies showing how the seabirds use the marine habitats are therefore important in order to understand what regulates the occurrence of the different seabirds both temporally and spatially. For example, some species spread themselves out over large sea areas in the winter season, while others stay close to limited coastal areas. During the breeding season they have a limited radius of action around the colony, and therefore use smaller areas.

Knowledge about the processes that govern the seabirds’ choice of habitat is important, both to explain the distribution and occurrence of the different species and to predict where the birds will be at different times of the year. This kind of knowledge is highly relevant, e.g. for all types of environmental risk analyses and impact assessments, and for investigations after the occurrence of episodic events. Such insight is especially valuable for the oil industry when calculating the effect of a potential accident at the population level, as well as informing the scaling of oil spill readiness.

The habitat use of the seabirds is studied either by direct observation from boats at sea or by the use of tracking devices attached to the birds. SEAPOP has used both satellite transmitters and different loggers for tracking, but in more recent years we have primarily banked on GPS or light loggers. Read more about our methods for mapping the birds’ migrations.

The mapping of the seabirds’ migration patterns is now coordinated within the SEATRACK project.

This ivory gull is carrying a satellite transmitter with a GPS on its back. The transmitter gives precise information about the bird’s movements.
Photo: Hallvard Strøm