Sevengill Shark, Notorynchus cepedianus
Sevengill sharks have seven gills on each side of their pectoral fins; most sharks have only five gills.
Sevengill sharks are found locally in San Francisco, Monterey, and Tomales Bays, but are also found in the South Atlantic, Pacific, and Indian Oceans.
San Francisco Bay may be the primary pupping ground on the west coast for sevengill sharks
Sevengill sharks are one of five common species in San Francisco Bay: the others are leopard, soupfin, spiny dogfish, and brown smoothhound sharks.
“Sevengill sharks are great to work with,” says Christina J. Slager, Director of Animal Care and Exhibits for Aquarium of the Bay. “Even though they’re the Bay’s apex predators, at Aquarium of the Bay, they’re like goofy aquatic puppies, waiting to be fed.”
Sevengill sharks are ovoviviparous, meaning they give live birth versus laying eggs, with 80 to 100 young born per pregnancy. Gestation for this animal can last up to two years. It is thought that San Francisco Bay may be the primary pupping ground on the west coast for sevengills.
The species is one of two in the cow shark family – the other being the sixgill shark – found along the California coast. The animal was heavily fished in San Francisco Bay in the 1930s and 40s, until the fishery collapsed. However, interest was re-piqued by sports fishermen in the mid 1970s, following the release of “Jaws” – arguably the worst ocean film ever created, in terms of its impact on the public’s perception of sharks.
While sevengill sharks are common in San Francisco Bay, little is known about their behavior and ecology. In one of its leading Conservation Impact Programs, Aquarium of the Bay’s biologists began working with the Biotelemetry Lab at the University of California, Davis in 2008, to implant transmitters into sevengills to collect valuable information on the sharks’ life patterns and basic ecology. Initial findings indicate a previously undocumented travel pattern in and out of the Bay. Further analysis is currently underway.
Aquarium of the Bay exhibits sevengills, along with all local shark species, in its Under the Bay exhibit tunnels. In addition to viewing these animals, visitors have the unique opportunity to watch the Aquarium’s Animal Care staff pole feed them underwater each Thursday and Saturday at 10:30am.
Catch a sneak peek of our weekly feeding presentations!