A. Agassiz, 1860 :
Phylum Ctenophora / Order Cydippida / Family Pleurobrachiidae
Pleurobrachia is seasonally one of the dominant predators in California waters, and may regulate the abundance of certain zooplankton prey. They are hermaphrodites and incredibly prolific - an adult can release up to 1000 eggs per day, and breeding can occur at all sizes. As a result, massive increases in population density can occur within inshore areas in a matter of weeks. Among the sea gooseberry's more dangerous threats is the voracious comb jelly Beroe, which slurps up whole comb jellies with its cavernous mouth. When a potential predator is detected, the direction of the comb row beat can be reversed, sending the sea gooseberry off in another direction and hopefully out of danger.
Although not always seen during excursions into Monterey Bay and other West Coast locations, during spring and summer months, Pleurobrachia can be incredibly abundant in surface waters. Due to the transparent body, they often are not easily seen in the water, but with a surface plankton tow the net may be totally packed after only a few minutes. P. bachei ranges from Alaska to Mexico; other closely related species of Pleurobrachia are found in the Atlantic Ocean and other temperate seas. The genus name (Pleurobrachia) is derived from the Greek, pleura (side) and brachion (arm). Sea gooseberries do well in captivity when maintained in a kreisel and fed brine shrimp nauplii and wild zooplankton. They are a popular display at public aquariums featuring jellies.
All photographs © David Wrobel and may not be used or copied without permission!Home