Tag Archives: Velella

Clinger crabs are members of wind drift community

Published February 3, 2018 in the
“Ocean Watch” column, Honolulu Star-Advertiser ©2018 Susan Scott

A pregnant clinger crab fits in the palm of a hand. ©2018 Susan Scott

When the wind is howling and the surf is busy salting everything in my house, I hit the beach. Those aren’t the best conditions for soaking up sun or playing in the water, but for us avid walkers it’s prime time for finding marine treasures.

Because I make mosaics from litter I find in albatross nests at Midway and on beaches in the Pacific, my gems are usually bits and pieces of colored plastic. Last week, though, my prize was alive. When I got home and dumped my junk in a colander for rinsing, there on a barnacle- and algae-encrusted toy truck clung an offshore crab.

This species of crab is a member of the wind drift community, a diverse bunch of animals that float on the surface eating anything they run into, including each other. They’re called wind drifters because they are indeed adrift, their direction and speed controlled entirely by current, wind and waves.

Common jelly-type critters floating offshore are Portuguese men-of-war (Physalia), by-the-wind sailors (Velella) and blue buttons (Porpita).

You might not expect snails to be members of this community, but two species are common: violet snails (Janthina) and snails-without-shells called nudibranchs (Glaucus).

Another unlikely offshore mariner is a little crab I call the clinger crab because it doesn’t have its own float system, as the others do, nor does it swim. Rather, the clinger crab spends its life hanging onto a piece of wood or debris. (I can’t find a common or scientific name for this little crab. If you have one, please write.)

Clinger crabs are about the size of a quarter and come in shades of blue or brown, depending on which object they’ve chosen to call home. This clinger was brown, a perfect match to the brown seaweed that grew on its floating toy.

You can tell a male crab from a female by the flap on the center of its underside. Narrow is male; females have wide flaps that hold their eggs.

When I examined my crab’s belly, I discovered, with some excitement, that I had a female with eggs. Hoping to raise some baby clingers, I rushed back to the ocean for a bucket of water, half filled my rescue tank and gave my pregnant crab her tiny truck, a pile of rocks to reach it and some frozen brine shrimp for energy.

A pregnant clinger crab fits in the palm of a hand. The eggs are the yellow mass under the flap. ©2018 Susan Scott

Alas, a tank being the utter opposite of her natural habitat, she did not survive. Even so, I was happy to have had a wind drift pet, even if just for a day.

During my beach walks I sometimes forget to bring a bag, and have to go trash-can diving for containers. Failing at both those things last week, I called Craig to come get me in the car, because I couldn’t walk home. After stuffing my pockets full of flotsam, I then filled my Crocs.

I have lived in Hawaii long enough that I sometimes think it’s too cold to go snorkeling. Never, ever, though, is it too cold for beachcombing.

Tiny velella sail by before stormy seas

By-the-wind sailor is a non stinging relative of jellyfish about 4 inches long and 3 inches wide. ©2014 Susan Scott

BUNDABERG, Australia » After a weeklong passage from New Caledonia, Honu is safely in a marina on Queensland’s south coast. Even so, my body thinks we’re still at sea because I have “mal de terre,” the French phrase for land sickness. This happens when the seas have been particularly rough.

The voyage didn’t start that way. For six days the wind was light, and the boat moved with a pleasant motion.

One day during those mild conditions, Craig noticed shiny disks dotting the water’s surface. They were by-the-wind sailors, the jellyfish relatives in the news recently after washing up on the U.S. West Coast by the millions.

Also known as Velella, the floating, nonstinging (to humans) creatures, about 4 inches long and 3 inches wide, bobbed on the surface as far as we could see.

I had read about enormous numbers of these creatures surrounding sailboats offshore, but this was the first time I saw it. The jelly boats ran downwind with us all day, their clear sails scooting them along while their tiny tentacles trolled for plankton. When a waved capsized them, the bottom-heavy animals popped back up and sailed on.

Because I had only seen these offshore animals dead on the beach, I wanted to see one alive in its element. Craig tied a colander to the end of the boat hook and scooped one up.

The jelly sailor was magnificent, its clear sail and blue hull radiant in the morning sun. After taking its picture, we returned the little boat to its fleet and wished it fair winds.

But none of us were that lucky. As we headed toward a 20-mile-wide pass through the Great Barrier Reef, lightning flashed ahead. With landfall only 100 miles away, we forged on. Soon thunder roared, lightning struck the water around us, and rain pounded with such force the drops felt like hailstones. We had sailed into the center of a storm.

As we breathed a sigh of relief over making it through hours of forked lightning and bellowing head winds, another thunderstorm appeared, lighting the leaping waves like a discotheque from hell.

That night we sailed through storm after exhausting storm, each time thinking it was the last. After four such tempests, the skies cleared, dawn broke and we sailed into the harbor of Bundaberg.

After friendly customs officers cleared the boat for entry into Australia, I walked to the nearby beach. There on the sand lay hundreds of Velella jellies, shipwrecked by the storms.

Even days later the ground still moves beneath my feet, and the sensation gives me a touch of nausea. But that’s OK. I’m just happy that unlike a host of our tiny fellow sailors, Honu made it safely to port.

Marine biologist Susan Scott writes the newspaper column, “Ocean
Watch”, for the Honolulu Star-Advertiser, www.staradvertiser.com

©2014 Susan Scott