Gray Whale Migration

Gray whale feeding off Cape Foulweather

Each October, as the northern ice pushes southward, small groups of gray whales start a two to three month 5,000 – 6,800 mile trip south. Beginning in the Bering and Chukchi seas and ending in the warm water lagoons of Mexico’s Baja peninsula.

Traveling night and day, the gray whale averages approximately 75 miles per day at an average speed of 5 mph. This round trip of 10,000 –13,600 miles is believed to be the longest annual migration of any mammal. By late December to early January, they begin to arrive in the calving lagoons of Baja. The three most popular lagoons are Laguna Ojo de Liebre, San Ignacio and Magdalena.

These first whales to arrive are usually pregnant mothers that look for the protection of the lagoons to bear their calves, along with single females seeking mates. By mid February to mid March, the bulk of the population has arrived in the lagoons.

Throughout February and March, the first to leave the lagoons are males and females without new calves. Pregnant females and nursing mothers with their newborns are the last to depart. These whales leave only when their calves are ready for the journey, which is usually from late March to April. Often a few mothers linger with their young calves well into May.

Populations of about 200 gray whales stay along the Pacific coast from Canada to California throughout the summer. Many of these whales stay here in Depoe Bay to feed on the abundance of mysid shrimp. During the migration gray whales feed very little or not at all. There are approximately 20,000 gray whales in the winter and spring migrations. A group of 200-400 whales feed along the Oregon coast during fall and summer.

From March through June most of gray whales make the journey from their breeding lagoons in Baja California to the Arctic feeding grounds. On this northbound migration, small numbers of gray whales fall out of the migration and stop at various locations along the Oregon coast. One of these places is Depoe Bay, these whales are called resident gray whales.