Subject: Re: Whale Excretion

KIm Marshall (
Fri, 26 Dec 1997 11:54:43 -0500

Thank you for your question regarding whale excretory systems.  Whales
have liquid excretions (both urine and faeces) and must deal with
ridding their bodies of excess salt by excreting it via urine and
faeces.  Whales have specialized kidneys that enable them to release
high salt concentrations via large quantities of urine.  Digestion
occurs in a 4-chambered stomach utilizing things like small rocks to
assist in breaking down food.   I don't know the standard whale stool
mass.  One calculation by E. J. Slijper, 1979 ,
<italic><underline>Whales </underline></italic>, states that 4/5ths of
the herring which dolphins eat consists of water, of which a maximum of
20% is lost by the production of faeces and by exhalation, so that 80%
can go into the productin of urine.  In addition whales have a high
metabolic rate and seem to oxydize fats moreso than carbohydrates and
proteins which causes them to lose even more water - thus excretion of
salt is critical as is maintaining appropriate fresh water levels in
the body.  Toothed whales such as orcas do not suffer as much from
fresh water loss as the larger baleen whales because they consume
things such as birds and other marine mammals that have a high fresh
water content in their bodies and opposed to krill which maintains the
same salinity level as sea-water.  

Faeces of whales will contain undigested materials like fish eyes,
squid beaks - depending on the diet of the particular species.  

I hope this information helps you.  Thank you and happy holidays.


I was curious about the whale's excretory systems.

>I know fish use the membranes in their gills to diffuse uric acid out

>their bodies, but, whales not having gills probably can't do this. So

>wanted to know if, like land mammals, whales had solid and liquid

>excretions and if so, were they constantly active or periodically. If

>periodically how much mass would be in the standard whale stool.

>Thank you.


Kim Marshall-Tilas                              (617) 259-0423

Whale Conservation Institute                   fax: 259-0288

191 Weston Road                                 website:

Lincoln, MA  01773		<italic>Are you a member of WCI yet?</italic>