Sharks in the Bay? Unsung Predator of the Depths

Sevengill Shark. Photo courtesy of Aquarium of the Bay

There are unseen creatures living under the surface and learning about a few of them can give the Bay new depth. The Great White Shark gets a lot of attention in the movies, but what about its toothy cousins? Introducing the Sevengill shark of San Francisco Bay!

Can I see one? Will it eat me?

The sharks like to hang out in deep water, up to 450 feet down. In the SF Bay they’re often found 60 feet below the surface, far from the deck of a ferry and still farther from the Golden Gate Bridge pedestrian path.  Your best chance to see one up close is to visit a local aquarium housing such fine beasts.  The sharks eat fish, seals, rays and other sharks. Your less buoyant, surface dwelling body is most likely not on their grocery list.

Where does the Sevengill shark breed? How long does it live? Are its numbers increasing or declining?

Sevengill sharks give live birth versus laying eggs. Between 80 and  100 young are born per pregnancy! Gestation can last up to two years. San Francisco Bay is thought to be a primary pupping ground. Aquarium of the Bay and UC Davis’ Biotelemetry Lab are currently doing research to better understand the behavior and health of these SF Bay natives.  The shark’s role in the bustling subsurface city is bound to be important even if we don’t yet know the full job description.

The Bay is right there, even in a traffic jam or windowless office; you know it’s an intersection or a glance away. These sharks, their prey and the constantly changing web of life, are just below the surface.  There is a brackish city teeming with life, relationships, and hardship in our backyard and we’re doing our best to help it thrive.