Great white shark populations may be alarmingly low in the northeastern Pacific, including off California, but they are not in danger of becoming extinct and do not warrant protection under the Endangered Species Act.
That is the determination of NOAA Fisheries, which had agreed to consider listing white sharks as endangered in response to two petitions submitted last year.
In a news release issued Friday, NOAA explained that a team of eight scientists determined, based on review of the best available science, that white sharks in the northeastern Pacific—from the Bering Sea to Mexico, out to Hawaii—have “a low to very low risk of extinction now and in the foreseeable future.”
While conservation groups and researchers will contend that white shark numbers are low enough to warrant listing—one recent study placed the California population at only 219 adult sharks—others believe that long-standing conservation efforts are working and that white shark numbers might actually be increasing.
“I keep saying that the recovery of the white shark population is probably one of California’s greatest success stories,” said Christopher Lowe, director of the Shark Lab at Cal State Long Beach. “And it’s based on the fact that it takes more than just protection of white sharks from fishing mortality back in the mid-1990s to accomplish this.
“It has required improving water quality, and restoring prey for juveniles and adults through better fisheries management and protection. Just look at the amazing recovery seal and sea lions have made off California alone!”
The Monterey Bay Aquarium, which has temporarily displayed live white sharks in the past and has participated in research projects with Stanford University and other institutions, issued a statement in which Margaret Spring, vice president of conservation of science, stated:
“The aquarium appreciates NOAA's thorough review and synthesis of the best available information on great white shark status and threats. We are fully committed to supporting rigorous science, public education efforts, and ocean policy reform to ensure that great white sharks do not become more vulnerable in the future.
“For more than a decade, the Monterey Bay Aquarium and our research colleagues from Stanford, UC Davis, CSU Long Beach, and other institutions have generated most of the data about adult and juvenile great white sharks in the northeastern Pacific. We will continue this work so we can gain a better understanding of population trends and the overall health of sharks that play a vital role in ocean health.”
In California, the Farallon Islands and other San Francisco Bay Area waters are primary seasonal aggregation spots for adult white sharks. They arrive each late-summer and fall to feed near elephant seal rookeries.
In Mexico, Guadalupe Island west of Baja California is the primary gathering place for white sharks during the same feeding season.
While these are primary aggregation sites, some scientists believe that because of the burgeoning sea lion population off the West Coast, particularly off Southern California, not all adult white sharks need to visit elephant seal rookeries each fall. Thus, it’s impossible to formulate an accurate population estimate.
Lowe, who has worked extensively with juvenile sharks off Southern California, cites as contributing factors for what he believes is a growing population: The Marine Mammal Protection Act of 1972; the removal of coastal gill-nets under Prop. 132 in 1990; and a long-standing California ban on fishing for white sharks.
“It’s always a good sign when the big predators start to return to coastal ecosystems,” Lowe said. “It means we’re doing something right to correct for our past abuses of the ocean. Of course, we’re not out of the woods yet, as there will always be new emerging problems as a result of an ever-growing human population. But this shows we have the ability to fix things when we put money and political will toward it.”
Some of those problems still exist in Mexico, particularly off Baja California, where there is no ban on nearshore netting, and where juvenile white sharks are often caught and killed by fishermen.