Re: Tears and 'salt excre

Bill Burnett (bbur@wpo.nerc.ac.uk)
Mon, 13 Nov 1995 09:15:45

In article <483j8h$2kf@kira.cc.uakron.edu> r3dlb1@dax.cc.uakron.edu (David L Burkhead ) writes:

>>I believe most of the fluid intake of marine animals (at least the carnivores)
>>comes from the tissue fluids of their prey, which may be slightly
>>hypotonic to sea water (depending on prey item) so reduces salt intake and
>>associated problems to some extent.

> Actually, I suspect that most of the fluid intake would come from
>incidental ingestion of seawater while eating prey items. When a
>baleen whale swallows a mouthfull of krill, it could not help but
>injest considerable seawater with it. Animals that eat "chunkier"
>food might have better space-filling in their mouths (less room for
>seawater in that mouthful), but still (and this is just my "gut
>feeling" make of it what you will) would probably swallow considerable
>seawater along with it.

Hmmmm.... I'm not sure. Baleen whales squeeze most of the water out of the
krill they eat with their tongues before swallowing... but krill do have lots
of places where water could get trapped... I wonder if an odontocete trying
to chew up and swallow a large fish is more efficient (in terms of swallowing
less water...) or not. (Will be sure to ask the next cetacean I meet. :-))

But this is kind of off the thread.... :-)

Bill