“One of the most important predators in the kelp forest is the California sheephead, a fish that changes sex during its lifetime,” says marine ecologist Edward Parnell. All California sheephead begin life as females and transmute into males at around 7 years of age. They remain male until they die, around 40 years later for those fish that are successful at evading predators.
Parnell says that sheephead are mostly sedentary in their adult lives, and loitering in the kelp forests makes them susceptible to anglers. When the sheephead are overfished, “The ability for them to eat down the largest sea urchins is diminished, and suddenly you lose control of an important kelp grazer. Sea urchins are a really important species in a kelp forest — when there are too many, they’re like a plague of locusts.”
On Monday, September 8, Parnell will speak at the Birch Aquarium at Scripps’s fall lecture series on marine-protected areas. “Traditional fisheries management is important, in terms of seasons and size limit. The science behind it is fairly sound,” says Parnell. “When it gets implemented into policy, it gets highly politicized. That process is happening now.”
Beginning in September, three groups — the South Coast Regional Stakeholder Group, the Science Advisory Team, and the Blue Ribbon Task Force (whose job it will be to assist with policy matters) — will meet to establish new boundaries for marine-protected areas for the south coast of California.
According to Parnell, it will be the regional stakeholders who will draw the prospective boundaries; the Science Advisory Team will determine how effective those boundaries would be. “We want to preserve enough animals to allow them to grow to a large size to increase their reproductive capacity. By protecting larger animals, you’re maximizing their reproduction.”
The kelp forest off the coast of La Jolla is about 5 miles long and 1.5 miles wide. One of the proposed reserves would encompass 42 percent of the kelp forest near the southern end of La Jolla. Scientists also hope to define a reserve in waters outside of both central and northern Point Loma. It is estimated that reserves in these areas would preserve 20 currently exploited species, including abalone, sheephead, and sea otter.
It’s especially important to safeguard the largest, most mature fish of each species. “You could put out a million larvae from smaller animals, but they won’t be as strong as they would if they were produced by larger animals.” Eventually, as populations increase, mature marine life will “start spilling out into non-protective areas, and suddenly fishermen will start reporting larger animals.”
As set forth in the Marine Life Protection Act-Initiative (created in August 2004), there is a year and a half left to finalize the boundaries for marine-protected areas along the Southern California coast. Parnell believes the Central California coast has had an easier time of conservation, as many of the protected areas in that region are not often frequented by humans.
“Here, almost everywhere is someone’s backyard, and every piece of rock is being fought over.” He believes peer enforcement and education are crucial to successful implementation. “A lot of fishing groups think it’s just a stupid law. But we can’t have a fraction of 1 percent of the population dictating state waters out three nautical miles.”
In the north central region, says Parnell, fishing is now banned in only 7 percent of the water. “A lot of what you hear, if you go to a tackle store, is, ‘They’re going to take away all the fishing between Oceanside and the Mexican border.’
“That’s not going to happen,” says Parnell. “It’s only a few selected areas.”
A Place of Their Own: Protecting Sea Life in California
Lecture by Scripps marine ecologist Edward Parnel
Monday, September 8
Birch Aquarium at Scripps
2300 Expedition Way
Info: 858-534-5771 or www.aquarium.ucsd.edu/