catlinaMysteries of the Sea Hare

by Gabbie Baillargeon

Cerulean blue waves crash over my head as I swim out past the surf break.  I have snorkel gear on complete with three layers of neoprene, as the biting April water was relentless.  Along with my AP Biology classmates, we embark on an adventure of epic proportions to beautiful Catalina Island, off the coast of California.  Back up a few hours to how we arrived on the island: there are 19 of us, our bus has 18 seats, and those seats are even smaller than the pitiful Southwest airlines seats.  If this wasn’t already a rather unfortunate circumstance, the last of our water had to be used to cool the leksfj which was continuously making the bus break down.  On about three hours of sleep, we frantically rush to catch the ferry, dragging all our luggage behind us as we board the ship.  Finally we spot an oblong shape rising up in the distance.  As my eyes focus, I see the magnificent island painted with tones of blue, green, and gold all set against Desert Mountains and extensive rocky tidal areas.

Fast forward to the next morning, as we awake to a beautiful sunrise which welcomes us into the calm water of the water of the early morning.  The crystal clear water provided amazing visibility, allowing my eyes to drink in all of the natural beauty the ocean had to offer.  Suddenly, a kelp forest rose up beneath and I could see thousands of kelp waving with the rise and fall of swells.  The highlight of the snorkeling expedition came when the instructor dove down and brought up, what looked to be a big black blob which I learned was a California Sea Hare!

I never knew such a creature existed!  Commonly they are known as Sea Slugs, but this one was a little larger that a football in size and had a unique silky, jet black coloring.  On the top of its head it had two protrusions which resembled rabbit ears, giving it the title Sea Hare; in addition, it possesses paranoia which look like ruffles extending down the length of their body.  Sea hares are both invertebrates and gastropod mollusks, meaning they have no backbone but instead a small internal shell.  They have a gelatinous consistency and their delicate skin is coated in mucus, when it was in my hands the longer it stayed there the thicker the mucus became and my hands were literally stuck to the sea slug!  Strangely enough, I did not mind that I was getting slimed, instead I was just filled with thev excitement of interacting with my new friend.

As I escorted my new friesea harend to meet the others, the instructor further educated us about the mysteries of the Sea Hare.  I was surprised to discover that stored within their mantle, are two types of mucus which they excrete (usually) for defense purposes.  Similar to a squid or octopus, sea hares can reflexively squirt purple ink, which deters predators; however, the ink is thought to contain toxins ingested from the red algae they consume.  Secondly, their opaline glands excrete a filmy white mucus that has recently been shown to block olfactory (smell) senses of predators, and thereby disorienting them and allowing the sea hare to escape.

 

The instructor then told us about their ambiguous gender(s).  Sea hares are hermaphroditic, and possess full reproductive organs of both genders – and can be a male and a female all at once!  Their reproductive cycle is really quite extravagant as they all gather in either circles, or lines, on beds of eelgrass.  The line leader must be a female (for the time being) and therefore behind her is a male.  Here is where it gets confusing –  discounting the first and last slugs in line, each individual is male to the slug in front, but female to the one behind, leaving a male at the end of the line.  An astonishing 80 million eggs per individual is produced in order to ensure that at least a few of those eggs reaches sexual maturity and continues to keep the species alive.  I was flabbergasted upon hearing about the extraordinary lives they lead!

Finally the time had come when we had to say our goodbyes, first to the sea hare and later to the island as a whole.  However, the images in my mind still resonate with the pure beauty of Catalina.