Subject: Re: Volume of blood in a blue whale

Dr. Cathy Schaeff (schaeff@american.edu)
Mon, 06 Oct 1997 10:30:34 +0000

Dorothy Snook wrote:
> 
> Dear Dr. Schaeff
> I'm trying to find out an educated guess of how much blood there is in a
> blue. Iunderstand that with most mammals it would be appoximately 8% of the
> total body wieght--but wondered if the amount of blubber in a whale's body
> (there being less blood in fat tissue) would change this forumla?? Thanks


Hi Dorothy,

I am not sure about the formula but your logic seems sound.  The amount
of blubber on whales varies between species (bowheads and right whales
probably have the thickest; in bowheads it may be as thick as 50 cm) and
varies also with season (thin at the beginning of summer and fat at the
end). Skin thicksness also varies.  Fat is laid down in other regions of
the body in addition to the blubber (organs, eg liver, tissue eg
muscle,  and in bones) and so fat (lipids) may account for as much as
50% of total body!  Your right about the blood flow being less in the
blubber.  Blood flow through the blubber is restricted to a fine network
of thin-walled capillaries which operate a 'counter-current' system
which helps redue heat loss.

So, this doesn't really help with your estimate -- just identifies all
the factor which make such an estimate a difficult thing to calculate
without direct measurements!

Wish I could be more helpful -- I'll keep looking for an estimate in
blood volume.  

cheers, Cathy Schaeff 
-- 
Dr. Cathy Schaeff
Biology Department 
American University
4400 Mass. Ave. N.W. 
Washington D.C. 20016-8007
(202) 885-2175 (phone)
(202) 885-2182 (fax)
schaeff@american.edu (email)