(Floating) Around the Pier

Recovered Sea Bass could aid in studies of La Jolla marine reserve

At the outset of a new project at Scripps Institution of Oceanography, UC San Diego to understand the La Jolla kelp forest's role as a Giant Sea Bass spawning ground, the carcass of a female Sea Bass of spawning age and condition turned up floating near the end of Scripps Pier.

Scripps divers spotted the fish and brought it ashore on Aug. 18. A fishhook and a short length of fishing line were attached to the mouth of the 125-pound specimen leading researchers at the Scripps Marine Vertebrate Collection to believe it was likely caught accidentally and released by an angler. Giant Sea Bass are a protected species in California and fishermen are required to release them if caught.

Grant Galland, a graduate student in the Marine Biological Research Division at Scripps, said that the trauma of the struggle with the fisherman and its rapid ascent to the surface likely caused the death of the fish.

Fishing of nearly every kind is illegal in the Marine Protected Area to the south of Scripps Pier but it was unclear where the catch took place. Scripps collections officials notified the California Department of Fish and Game but were allowed to keep the specimen after a brief investigation by Fish and Game wardens. It is now the largest sea bass specimen in the collection.

The Giant Sea Bass is not an endangered species but has been protected off the California coast for decades after years of overfishing decimated local populations. The exact lifespan of the species is unknown but specimens have been known to reach as much as 560 pounds and 2 meters (7 feet) long. Collections officials estimated the recovered female to be around 15 years old. An examination of its ovaries revealed it to be carrying eggs, possibly to return to the kelp forest for mating season, which typically takes place in August and September.

The acquisition of a local Giant Sea Bass is rare because of its protected status. Researchers said the find represents an opportunity to learn more about the once-plentiful resident of the La Jolla kelp forest. Galland and postdoctoral researcher Brad Erisman coincidentally have tagged six Sea Bass thought to reside in the reserve in an effort to understand their migratory patterns in relation to the spawning season and reserve boundaries.

"The La Jolla reserve is one of only a few areas in California where these animals are afforded full protection," said Erisman. "We hope to understand how these animals use the reserve for feeding, reproduction, and as nursery grounds and which types of habitats and areas within they reserve are preferred. "

—Robert Monroe

September/October 2009