California’s set gillnets have one of the highest discard rates—by the number of animals—on the West Coast.
Commonly confused with the infamous drift gill net, this little-known fishing gear type is being used in offshore Southern California waters. Southern CA Set Gillnets has been operating relatively unchecked over the last two decades. The government has allocated little to no resources for a monitoring or observer program, and it is unknown how many set gillnets were deployed over the last decade, making it difficult to estimate the full impacts of this gear on marine wildlife and its population impacts.
Only 39 estimated participants who fish with set gillnets are left, primarily targeting halibut and white sea bass. Sixty-four percent of animals caught with set gillnets are tossed overboard, translating to a conservative estimate of over 230,000 animals thrown overboard from 2007 to 2021, with over 50% dead before hitting the water.
Although commercial fish landings data indicate the number of discarded animals during this period could be as high as 2 million. Set gillnets catch 125 different species, and only 17 species are primarily kept and sold. Nearly three of every four sharks, rays, and skates caught are tossed overboard in the set gillnet fishery.
Set gillnets are the primary threat to juvenile great white sharks in their nursery grounds off California. White sharks play an important ecosystem role, and their population is still at low numbers. These nets present a grave risk to marine mammals, including cetaceans like humpbacks, gray whales, and pinnipeds. Set gillnets kill more California sea lions annually than all other observed West Coast fisheries combined.
Set gillnets have historically entangled endangered Pacific leatherbacks, and because they are still mostly unobserved, we don’t know the impact this gear type has had on this critically endangered species.
Set Gillnets have been banned in Northern California since 1915. After a series of advocacy campaigns between sport anglers and environmentalists in the late 1980s and 1990s, California voters passed Proposition 132, effectively banning set gillnets in state (zero to three miles inshore) waters off Southern California. In the late 1990s, scientists discovered set gillnets were killing an alarming number of federally protected marine mammals and seabirds off the state’s central coast. In response, the California Fish and Game Commission banned the usage of these nets off the central coast in 2002. In areas where set gillnets have been banned, regional populations of vulnerable species have recovered to healthy population levels.
Today, set gillnets are still allowed to be used offshore (three miles-200 miles) in Southern California and are managed under the jurisdiction of the state of California. Management tools are available to reduce bycatch in California’s set gillnet fishery, and a more selective hook and line fishing method for California halibut and white seabass is already well-established.
As climate change continues to create a harsher environment for many of these vulnerable marine species, we must address the threat set gill nets have on California’s biodiversity.