Beluga whales prefer habitat around the river plume
Estuaries along western Hudson Bay are summer habitats for beluga whales, as well as areas with increasing vessel traffic and tourism. This area is under consideration to become a National Marine Protected area. In this paper, we determined which areas are important for belugas, and what environmental features make the habitat suitable to them.
Read this open access paper on the Arctic Science website.
A photographic survey of the Nelson, Churchill, Seal and Knife River estuaries was used to identify beluga locations. Environmental characteristics were collected in these areas, including using satellite images to measure water quality and the boundaries of the river plume.
Through habitat modeling, we found that differing environmental characteristics separate five distinct beluga habitat areas, the Seal River estuary, the Knife River estuary, the Nelson River estuary, and the Churchill River outer and inner estuary.
By comparing which of the environmental features among the available ones were preferred by belugas we were able to determine that river plume, distance to river mouth, and water quality characteristics (including total suspended sediment and coloured dissolved organic matter concentration) are important determinants of optimal beluga habitat.
Freshwater/saltwater mixing and water quality indicators can represent the amount of productivity in the area through inputs of nutrients that contribute to the food chain. This suggests that beluga habitat occupation may be related to prey availability.
Additionally, the models were used to map important habitat areas. We suggest our results should be considered for establishing protected areas and can contribute to a better understanding of beluga estuary habitat use across the Arctic.
Read the paper — River-influenced beluga (Delphinapterus leucas) summer habitat use in western Hudson Bay, Canada by : Emma L. Ausen, David G. Barber, Atreya Basu, Jens Ehn, David Walker, Laura Dalman, and Marianne Marcoux
