Status report on Cook Inlet belugas (Delphinapterus leucas)

In June 1991 aerial surveys were flown to determine the population size of the Cook Inlet stock of beluga whales. Strip and nearshore transects which paralleled the general outline of the shore were flown.

Because the Beluga whale (Delphinapterus leucas) population in Cook Inlet, Alaska appears to be a small and geographically isolated population, human-induced disturbances could have a dramatic effect on the stock. The summer concentrations of this stock are exposed to the largest industrialized coastal area and the largest human population in Alaska. This report will discuss the stock's distribution, population size, food habits, reproduction, subsistence harvest, and recommendations for monitoring the status of the Cook Inlet beluga whales.

Surveys in Cook Inlet have been limited to the concentration areas in the upper Inlet (Hazard, 1988). The estimates for the size of the population from these aerial surveys have generally ranged between 200 to 500 individuals. Beluga carcasses from harvested and stranded animals in Cook Inlet should be sampled whenever possible to collect information on age, diet, and reproduction. The use of intrusive collection methods should be avoided.