7 ‘ A
WNW-“din?”
Because little sediment accumulates in
thc rocky intertidal. deposit feeders are
rare. Most of the sessile animals are filter
feeders. They are unable to feed when
the tide is out. For one thing. thcy havc
to be under the water to filtcr it. Further-
more, many of them “clam up” during
low ride to avoid water loss and can’t cx-
tend their filtering or pumping appara-
tuses with their shells dosed.