n a recent sailing voyage aboard the oceanographic research vessel Robert C. Seamans, we scooped up an odd-looking animal that got everyone on board the ship excited. It was late in February, summer in the Southern Hemisphere, and we were about 100 miles off the northernmost tip of Aotearoa New Zealand, a point known as the North Cape. Here we deployed a meter net, a long finemeshed conical net with a 3-foot-wide metal ring that keeps the top open as it gets dragged through the water. For three nights in a row we sent this meter net down several hundred feet beneath the surface, towing it as we sailed very slowly along. Each time, when we hauled the net back aboard,
Animals in Sea History
sea education association
SEA HISTORY for kids
Students deploy a meter net from the deck of SSV Robert C. Seamans.
we found inside a glowing clump of clear rubbery pickle-looking, um… thingies. The thingies we captured in our net were colonies of living organisms covered by nubby spikes. Our chief scientist, Jan Witting, explained that each nubby spike is its own animal: a zooid with a simple brain, stomach,
by Richard King
liver, and a basket with cilia that acts as a filter. All of these zooids, each a clone of its neighbor, connects to the others with a clear gelatinous material that forms a firm sock-shaped colony, which opens on one end. These colonial organisms are pyrosomes. The first Western author to describe and formally name what some sailors called “sea pickles” or “sea cucumbers” was the French explorer and naturalist François Auguste Péron, who in the early 1800s encountered a large patch of them one night at the surface in the equatorial Atlantic. “Heightened by the surrounding circumstances,” he French naturalist François Auguste Péron was the first to formally describe and name the pyrosomes.
wrote, “the effect of this spectacle was romantic, imposing, sublime, riveting the attention of all on board.” Péron brought several specimens on deck, all between 3 and 7 inches long. He described their anatomy, tested their bioluminescent properties, and gave them their scientific genus name of Pyrosoma, which means “fire body” in Greek. In the decades to follow, other sea-going naturalists wrote about pyrosomes with similar poetic awe. American Francis Allyn Olmsted said that when big seas crashed over the rail, the jelly-like creatures rolled SEA HISTORY 171, SUMMER 2020