Subject: Why do Stranded Whales Die?

Kim Marshall (
Wed, 20 Oct 1999 08:26:54 -0400

Re: Why do whales die when they strand (or beach themselves)?
Dear Dino Llarde:
When whales, including small whales or dolphins become stranded on beaches
they suffer from the pressure of their own weight on their organs,in the
water they are weightless.  They also suffer from overheating as they have
blubber that insulates them in the water and outside of the water causing
them to overheat.  This is why we place wet towels and cold water on their
fins and flukes when do they strand to help keep their body temperature
down.  Unfortunately most stranded whales do not survive once they have
beached themselves.

No one really knows why whales strand but with networks managed by the
National Marine Fisheries Service and NOAA we are learning more and more
every day. Most mass strandings of whales occur with toothed whales that
live in pods with social hierachies like dolphins and piliot whales.  It is
beleived that if the leader of the group gets sick or disoriented the
others simply follow the leader onto the shore. Others believe that if
there is a illness throughout the group they will mass strand and die so as
not to transfer disease.

Another theory is that their sonar used for navigation may get absorbed by
particulates in the water near areas with a lot of upwelling ie: Cape Cod,
causing them to misinterpret information and basically they end up crashing
on land.

The last, but not least is the theory of the earth's magnetic pull and the
possible affect it may have in certain geographic areas on their ability to
navigate.  Whales have a mineral in their heads called magnetite which
might confuse their abilities to navigate when near land masses that can
react to this mineral.

I would recommend contacting the Marine Mammal Stranding Center, at this
web address: or utilize the vast information available
through WhaleNet at  Good luck!

I found your e -mail address while doing a Yahoo search for answers to a
question my daughter has. For a school assignment, she has to find out why
whales die when they get beached. I guess that other than the obvious
answer of not being able to get back in the water, her teacher says it has
something to do with water pressure. I assume that because whales live deep
under the water, their anatomies are better suited to that environment, so
that when they do get beached for an extended period, their blood vessels
probably burst or something. Is this even close? Thanks!

Kim Marshall-Tilas
Whale Conservation Institute/Ocean Alliance
191 Weston Road
Lincoln, MA  01773
(781) 259-0423
fax: 259-0288