Subject: Re: kelp mammals

Kim Marshall (
Thu, 20 May 1999 20:30:52 GMT

>Question:  What annimals eat the most kelp?
Reply: Dear students,
The major predator of kelp is the sea urchin.  They can, in fact, devestate
entire beds of kelp.  They feed on the holdfast (the equivilent of
terrestrial plant roots), so the entire plant can wash away and up onto
shore.  West coast urchin populations used to be kept in check mostly by
sea otters and east coast urchin populations were mostly controlled by
lobsters.  However, since both sea otters and lobsters have been heavily
harvested by humans, urchins have become overpopulated.  Now that the sea
otter population is rebounding off the west coast, urchin populations are
dropping back down to manageable sizes and the kelp is making a comeback.

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