One rather ignored shark species is gaining some respect in the Bay Area. The cow sharks, of which there are two different species in California waters, have been important at times in the history of California’s fisheries.
What I didn’t know is that, as predators, cow sharks are exceeded only by the great white.
According to “California’s Living Marine Resources: A Status Report” published by the Department of Fish and Game, sevengill cow sharks are at the top of the food chain, willing and able to take down marine mammals. They also eat other large sharks and rays, and other fish.
One interesting trait described in the report was the way sevengills will cooperate in packs to hunt and kill marine mammals including seals and dolphins. They are not particular about food sources, and have been known to feed on whale carcasses. One of the popular baits used to catch them are squid and salmon trimmings… testimony to the fact that they are probably feeding on just about anything reasonably fresh dead that they find on the bottom.
Sevengills come big, reaching lengths of 10 feet, and weights over 300 pounds. Heck, when born, they are 14 and 18 inches! They grow quickly, doubling their size in the first two years of life. At 5 feet, the male sevengill is mature, while the females don’t mature until they are 7-plus feet long. That means all those 3- and 4-foot sevengills you are catching are just babies.
There are a couple issues involved with fishing for sevengills that responsible anglers should be concerned about. Number one, this is a sensitive resource that can be easily impacted by overfishing. History supports this. In the 1930s and ’40s, sevengills were targeted commercially, resulting in a collapse of the population. In the ’50s and ’60s, restoration of the population was hampered by competitive shark fishing. Things were quiet for the big sharks, then along came “Jaws,” exciting a whole new wave of interest in catching sevengills.
For the ’90s, a whole new awareness of the sevengill cow shark vulnerability feathered the angler interest. A few charter boats focused on the fishery, encouraging catch and release. Biological studies by the Monterey Bay Aquarium has helped understand the big ’uns, but there is much that remains unknown about the sevengills, and their more broadly based cousins the sixgills.
“I’ve never been so humbled by a fish in the bay,” said Captain James Smith on the California Dawn, who recently took a few hours out with a shark charter to target the bigger fish in the deep water of San Francisco Bay. Fishing in 100 feet-plus, his group lost some five or six fish per one boated. In some cases, the fish bit clean through the leader; in others, they rolled up the wire leader and their abrasive skin shredded the mono line. Such monster action is addicting; “We’re going again,” said Smith. “But it’s just going to be a small group of regulars. I don’t think I’d want to promote catching these things, they are too vulnerable.”
There are two main spots along our coast you can get into some sevengill action, in San Francisco Bay and Humboldt Bay. I imagine there are some in Tomales Bay, and perhaps around some of the spots like Bolinas Bay and Drakes Bay. The bigger ones like the deep water, but the juveniles can be caught right alongside leopards and soupfins in the shallower south bay flats. Top baits are squid and live baits like sardines and midshipmen, but they’ll take a variety of other baits, including Berkley Gulp! baits, which are a little easier to handle.
Just remember that if you decide to spend some time on these big monsters, please catch-and-release, particularly on the bigger females. It takes years for these giant cows to reach breeding age, and killing one is pointless- if you must, keep a smaller male for the table.
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