About Migration:
Migration is the seasonal movement of animals from one place to another. Many species of whales migrate from feeding grounds to breeding grounds - some traveling long distances. Some whales migrate latitudinally (north-south), some move between onshore and offshore areas, and some do both.
Where Whales Migrate:
There are over 80 species of whales, and each has their own movement patterns, but in general, whales migrate toward the colder poles in the summer and toward the more tropical waters of the equator in the winter. This pattern allows whales to take advantage of the productive feeding grounds in colder waters in the summer, and then when productivity lowers, to migrate to warmer waters and give birth to calves.
Do All Whales Migrate?:
All whales in a population may not migrate. For example, juvenile humpback whales may not travel as far as adults, since they are not mature enough to reproduce. They often stay in cooler waters and exploit the prey that they can during the winter.
What Whales Migrate the Farthest?:
Gray whales are thought to have the longest migrations of any marine mammal, traveling 10,000-12,000 miles roundtrip between their breeding grounds off Baja California to their feeding grounds in the Bering and Chukchi Seas off Alaska and Russia.
Humpback whales also migrate far - one humpback was sighted off the Antarctic Peninsula in April 1986 and then resighted off Colombia in August 1986, which means it traveled over 5,100 miles.
Whales are a wide-ranging species, and not all migrate as close to shore as gray whales and humpbacks. So the migration routes and distances of many whale species (the fin whale, for example) are still relatively unknown.
Sources:
- Clapham, Phil. 1999. ASK Archive: Whale Migrations (Online). Note: Accessed online October 5, 2009. As of October 17, 2011, link no longer active.
- Journey North. 2009. Gray Whale Migration (Online). Accessed October 5, 2009.
- Mead, J.G. and J.P. Gold. 2002. Whales and Dolphins in Question. Smithsonian Institution Press: Washington and London.
