Subject: Blue Whale Habitat (fwd)

Michael Williamson (pita@whale.simmons.edu)
Tue, 31 Dec 1996 12:02:07 -0500 (EST)

Date: Mon, 30 Dec 1996 14:05:12 -0500 (EST)
From: Robert Kenney <rkenney@gsosun1.gso.uri.edu>
To: OStutte@aol.com
Cc: pita@whale.simmons.edu, krill@whale.simmons.edu
Subject: Re: Blue Whale Habitat


On Sun, 29 Dec 1996, OStutte@aol.com wrote:

> Please describe the habitat of a blue whale, and how it adapts to it.

ZOWIE!  This is a question that someone could spend a career researching a
complete answer.  Two short answers - in opposite order from your questions:

(1) An animal does not adapt to its habitat.  Over its evolutionary
history, natural selection makes a species become adapted to its habitat. 
A blue whale (or any other living organism from virus to bacterium to
redwood tree to mushroom to amoeba to jellyfish to bumblebee to human) is
adapted to its habitat because its ancestors which were better adapted
survived and reproduced better than others who were less well-adapted.

(2) The habitat of blue whales includes most of the ocean, probably with
the exception of extreme tropical waters.  Their feeding occurs during the
warm part of the year (which occurs at opposite times of the year north
and south of the equator) at higher latitudes, as far poleward as the edge
of the ice.  They feed almost exclusively on shrimp-like euphausiids
("krill"), which are most abundant in ice-edge and upwelling zones. 
During the colder season, they stop feeding and migrate toward lowere
latitudes to their wintering grounds, which are thought to be in deeper
regions in the center of ocean basins. 

For more information on blue whales, see almost any good book on whale
biology.  For a good history of our exploitation of the blue whale, with
one long chapter (a little out-dated) on biology, check out "The Blue
Whale," bu George L. Small (Columbia University Press, New York, 1971, 248
pp.).

Cheers,
Dr. Bob Kenney