In late June, Monterey Bay Aquarium staff were on a routine collecting trip off of San Francisco. It hadn’t been a particularly successful day, but that was about to change. “We were just about to pack it up and head back to the harbor,” said Senior Aquarist Kevin Lewand. But just then, Senior Collector Joe Welsh brought in a 7-foot, 5-inch, 113-pound male sevengill shark. It’s now thriving and on display in the Monterey Bay Habitats exhibit.
A Top Predator
The Aquarium has a history of large sevengills (Notorynchus cepedianus). A nine-foot specimen was on exhibit from 1990 to 1994, and we’ve had three over eight feet. Sevengills in the wild can reach a remarkable 10 feet in length, and feed on almost anything, including other sharks, rays, dolphins and seals. Among top nearshore predators, only the white shark reigns above the sevengill. According to Kevin, attacks on humans are rare, but at least one instance has occurred in California. (If this concerns Kevin, it’s not apparent, as he swims with the Aquarium’s sharks several times each week, as you can see in this video.)
Conservation
Like many sharks, sevengills are primitive, having been around for an estimated 100 million years. During the 1930s and 1940s sevengills, valued for their liver oil, were overfished in San Francisco Bay. They have rebounded and today are fished recreationally.
Still, sharks worldwide are in trouble. It's estimated that 100 million sharks, skates and rays are caught and killed each year—and that half of these are accidental victims of fishing gear that targets other species of commercial fish. Populations of large sharks and other top ocean predators have fallen by as much as 90 percent in recent decades.
One reason that the Aquarium displays large sharks—like our impressive new sevengilll—is to increase awareness of these issues and highlight the challenges sharks face worldwide.
Learn more about what the Aquarium is doing to help save sharks and how you can help.
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