In the summer many populations are found in warm-water estuaries and river basins. Belugas seem to be well adapted to both a cold ocean habitat and a warmer freshwater habitat. C. Migration- 1. Some beluga populations make seasonal migrations, while others remain in a relatively small area year-round. Environmental conditions determine migration behavior.
Most beluga whales migrate south as the ice pack advances in the autumn.
One population of beluga whales spend their summers in the Mackenzie River estuary of Northwest Territories, Canada, and migrates 5,000 km. Many populations of belugas migrate north in the autumn. Belugas that spend the summer in Hudson Bay estuaries migrate north into the open bay in the winter. Belugas may migrate to either shallower or deeper waters. Because the Beluga whale lives in cold water of different depths it has always lived in the northern parts of the world.