Green Sea Urchin Dedicated to Dan Morris ("Ursas and urchins...") Good luck on
the MCATs Dan! The green sea urchin is an extremely voracious predator, scouring
algae off the rocks of the Atlantic from the Arctic to New Jersey and the
Pacific from Alaska to Puget Sound. They are extremely vulnerable
to environmental stress and bird predation however, which restricts them
to subtidal regions or deep tide pools. They aren't very common in bays
and estuaries where saliniy varies, due to their inability to osmoregulate
well. They eat soft algae by using a mechanism called Aristotle's Lantern,
a group of 5 teeth with amazing range of motion. Huge "fronts" of urchins
can clear huge areas, leaving them devoid of all but the hardest coralline
algae. Aside from birds,cod, and occasionally sea stars, their other major
predator is man, who harvests them
for their eggs, which are a delicacy in Japan. Sea otters also eat a
lot of them on the Pacific Coast. Sea urchins are
echinoderms, which means they have a hard exoskeleton (echinoderm means
"spiny skin"), and a water vascular system which is used to move and
articulate both tube feet and spines.
Take me back to the Species of the
Week!
(Strngylocentrotus droebachiensis)
Take me back to the Main Page!