Pacific Basking Sharks Decline Dramatically
Eastern North Pacific basking sharks have been designated a species of concern by the National Ocean and Atmosphere Administration’s (NOAA) Fisheries Service. The reason stated for the designation is a dramatic decline in population, even with a decrease in fishing for the large sharks.
In their official press release, the Fisheries Service state, “We expect that by identifying it as a species of concern we will raise public awareness of the species status, generate interest in additional research to identify factors that may be inhibiting its recovery and, with states and other partners, restore this population before listing under the ESA becomes necessary. ”
In NOAA’s Basking Shark profile, the Fisheries Service states no large groups have been documented in California waters in the last 17 years, “Where schools in the hundreds and thousands used to occur off California, no more than 3 individual basking sharks have been observed at any one time since 1993″ (Phillips 1948, Squire 1967, 1990, McFarlane et al. 2009). The same document indicates the population is only slightly larger in Canada, “Only 12 sharks have been documented since 1996 (McFarlane et al. 2009).” Yet the official NOAA population estimate is 300-500.
The Pacific Wildlife Foundation’s population view seems to be more in line with the tiny number of documented sightings, “The minimum historical population was about 750 sharks compared to near zero now (COSEWIC 2007).”
Canada has listed the North Pacific Basking Shark as endangered, as well as the IUCN Red List. Pacific Wildlife Foundation also says the number of documented sightings in Canada is six, not twelve like the NOAA document states, “There are only six confirmed sightings on Canada’s Pacific coast since 1996. ” What exactly does it take for the North Pacific Basking Shark to be listed on the U.S. Endangered Species Act?
Basking shark’s reproduce infrequently, so once their numbers have been driven down to such a low point, recovery is difficult. Basking sharks don’t reach sexual maturity until the age of 16-20, and the gestation period is 2-3 years.
The information in the NOAA profile and expanded in the Canadian one, appears to suggest the species is a prime candidate for protection by the U.S. Endangered Species Act, and the designation as a “species of concern” should have probably been assigned decades ago.
Basking Sharks are a gentle giant. They pose no threat to humans and eat zookplankton.
Image Credit: Public Domain