whale sex

From: Phil Clapham (phillip.clapham@noaa.gov)
Date: Wed Apr 19 2000 - 08:22:01 EDT


Whales have sex in the same way other mammals do. Sort of. The basic
anatomy is the same except that the penis is rectractile; held inside
the body (to avoid drag in the water!) until needed, then it emerges
from the genital slit which is on the underside of the caudal peduncle
(the bit at the back heading towards the tail). Likewise, the testes
are internal, which of course presents some huge problems in terms of
cooling (since heat destroys sperm or limits pserm production), and
cetaceans have developed some remarkable counter-current mechanisms for
cooling the genitals internally.

The penis is fibroelastic rather than vascular, and copulation is
probably very brief (as it is with other mammals that have a
fibroelastic penis - e.g. ungulates like antelope). Copulation itself
has been witnessed in remarkably few cases in large whales. Seen quite
a bit in right and gray whales, and never in humpbacks. Surface
copulation occurs in the former two species sometimes, but presumably
most mating takes place quickly underwater. The penis is curved and has
a mobile tip, so in large whales a male will often extend his penis over
the body of a female (lying upside down at the surface) and into the

Now for the fun part. Not all whales are created equal in terms of
genital equipment. Blue whales, which are the largest animals on Earth
(males around 80 feet in many cases, weighing perhaps 100 tons or more)
have a pair of testes that weigh a "mere" 26 kg - remarkably small for
such a giant beast. Right whales are at the other extreme; a male which
may be half the length of a large blue whale male, and weigh a lot less,
has testes wweighing - wait for it! - one ton! Largest in the animal
kingdom. The reason is the mating system, which in right whales in
heavily skewed towards sperm competition (multiple males mating with the
same female and competing to produce as much sperm as possible, rather
than fighting it out on an individual basis the way, say, humpbacks do).

Phil Clapham

Loady99@aol.com wrote:
> Hey Phil,
> I was just sitting here wondering how whales have sex. If it is at all
> possible, please e-mail me back with an answer. I have always been very
> interested in whales and their mating techniques, but I just never got a
> complete answer.
> Thanks a lot, shane morris


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

tel (508) 495-2316 fax (508) 495-2066 Internet: phillip.clapham@noaa.gov

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