Subject: whale baby-sitting and sand-digging!

Leah Gerber (leah@fish.washington.edu)
Mon, 23 Mar 1998 22:20:58 -0800

At 08:29 PM 3/17/98 -0000, you wrote:
>Dear Dr. Gerber,
>	We have been studying whales for the past month in our class.  We have a
>few questions we haven't found the answers to yet.  We hope you can help us
>with them.
>
>1.  In which ocean of the world do most whales live in?
>
>2.  Would another whale take care of a baby that wasn't hers?
>
>3.  Do any kind of whales dig into the sand?
>
>We have enjoyed studying whales and have learned a lot about them.  We hope
>to hear from you soon.
>Thankyou.
>				Fellow whale watchers,
>					Mrs. Tower's second grade class
>				

Hello!

Very interesting questions.  I am glad to hear that your class has taken an
interest in learning about whale biology.  

To answer your questions:

1. This is a difficult question because each ocean includes different
species compositions.  Some ocean basins include few whale species but many
dolphin species. Some oceans include many different species of whales but
sightings are rare and scientists do not know much about how many animals
are there.  So there is no simple answer to the question.  Different
species of whales like to live in different habitats so the number of
species in a given ocean also depends on the type of habitat available.

2. I am not aware of any instance where a mother whale would care for a
calf that was not hers.  Female whales do not interact very much, so I
would not expect that mothers would help take care of other females calves.  

3. Yes, gray whales dig into the sand while feeding on benthic
invertebrates.  They are sometimes called 'mud suckers' because they suck
in mud while filtering out prey. Their favorite food are amphipods.
Amphipods, an order of the phylum arthropoda, are shrimplike crustaceans
that have no carapace. Of all phyla in the kingdom Metazoa, arthropoda
contains the largest number of species, 923,000; of which approximately
4,000 are amphipods.  Amphipods build mucus-lined tubular burrows, which
bind their sand habitat into a firm mat that resists erosion in response to
currents.  In addition to providing a primary food source for gray whales,
amphipods are an important prey item for a number of fish and bird species.   

I wish you the best in your whale studies,

Leah