Subject: Killer Whales

Phil Clapham (
Tue, 19 Jan 1999 07:36:58 -0500


No, no whales are monogamous.  Monogamy is very rare in mammals
generally.  It's more common in birds, but even there genetics work has
shown that birds aren't as faithful as they were once thought to be!

The mating system of killer whales isn't clear because no one's seen
them mate.  They live in tightly knit groups that appear to be remain
together for life, which means they must mate with animals from other
groups.  Whether they mate with a single partner in a season or several
is unknown at this point, but monogamy - two individuals remaining
faithful to one another, and pair bonding for a long period - is not one
of the options.

It's true that only one kind of killer whale eats marine mammals.  These
are the so-called "transient" type, which differ from the "resident"
type which eat fish.  The two terms were applied a long time ago and
they're rather misleading but they've stuck.  Residents and transients
may look alike, but they have virtually nothing to do with each other
and they are genetically very far apart.  They're probably undergoing
speciation - that is, the process of becoming separate species.

Phil Clapham

TR & Wanda wrote:
> Are Killer whales monogamous or do they mate with several partners per
> season?  Is it true that only nomad killers eat sealions and other mammals
> and pod whales only eat fish?


Phillip J. Clapham, Ph.D.
Northeast Fisheries Science Center
166 Water Street
Woods Hole, MA 02543

tel (508) 495-2316
fax (508) 495-2066