Harbour seal population dynamics

Knowledge on pinniped population dynamics for Icelandic conditions is scarce. Due to the recent rapid decline in the Icelandic harbour seal population the importance of further research in this area is increasing in importance. As an example, North Atlantic Marine Mammal Commission (NAMMCO) has recently recommended that Iceland increases research on population dynamics to facilitate a foundation for a revised and evidence based management plan for the Icelandic harbor seal population.

In this project we investigate several ecological parameters associated with the harbour seal population, such reproductive success, pup production and pup survival. Further, we aim to identify timing of biologically important periods (pupping, mating and moulting periods), as well as factors affecting when these periods occur. We also investigate haul-out behaviour of harbour seals and how environmental factors such as weather and tide height, as well as season, can affect the haul-out of harbour seals.

Knowledge on pup production and pup survival is extremely important for the implementation of seal hunting management. Such information, along with knowledge on population trends, creates a foundation for the number of animals that can be removed from a population on an annual basis. Identifying the timing of biologically important periods, as well as factors that affect the timing, is also important. As an example, the harbour seal census is carried out during the moulting period since we know that a larger proportion of the population is hauling out during the moulting period compared to other periods. Therefore it is important to make sure that the aerial survey is carried out during the peak of the moulting period.

To obtain the data we need meet the aims of the project, we do direct observations and counts of harbour seals in different haul-out sites during different conditions and during different time of the year. We also use wildlife track cameras in remote areas, and have recently explored the possibilities of using photo identification methods to study animals on an individual basis.