Sea hares!

Wow! We saw SO many sea hares on our trip to the Coal Oil Pt tidepools on April 16th.  The California sea hare (Aplysia californica) is a gastropod mollusk (think common garden snail) without an external shell.  This species is found along the California coast.

Some interesting notes about its physical characteristics:

Alpysia has two pairs of tentacles on top of its head: one pair up front near the mouth that help in movement and another behind the eyes used in olfaction. It is the large anterior tentacles, which resemble the ears of a hare, that are responsible for the common name - sea hare.

The color of sea hares, which can range from purple-reddish-brown to greenish-brown, depends on the color of algae they eat.  This year we saw many sea hares that were definitely more on the green end of that scale, which makes me wonder if there is different availability of algae from previous years.

These guys can get big - CA "brown" sea hares (Aplysia californica) can get to be up to 40 cm (16 in) long.  However its close relative - the California black sea hare (Aplysia vaccaria) gets even bigger, up to 75 cm (29 in), making IT the largest gastropod in the world.

And about its reproduction....
we mentioned in the field that sea hares are hermaphrodites - simultaneously both male and female.  For a peak at their mating "strategies" check out this National Geographic video entitled "World's Weirdest - Underwater Love Chain" !!

 and links to previous entries about rocky intertidal trips are here.