Wildlife White sharks rebound in California The long arc of environmental regulation is rebuilding a damaged ecosystem.

Most of the millions of beachgoers who flock to southern California’s coast never notice the baby sharks swimming laps just offshore, but that’s starting to change. The sharks aren’t on the prowl for sunblock-glazed snacks: the Southern California Bight – the coastal waters from Santa Barbara to the U.S.-Mexico border – is a white shark nursery. It’s where the young predators hide out, stay warm, and learn to hunt, before joining adults in deeper seas. Though their species has long been declining, baby white sharks are making a surprising comeback in the Bight.

Their return tells a bigger environmental success story: federal and state regulations stretching back 40 years have curtailed pollution and repaired the marine food web that includes white sharks (formerly called great white sharks). “You can’t have an ecosystem that’s badly damaged and have predators,” Chris Lowe, director of the Shark Lab at California State University-Long Beach, says.

Steve McNicholas

Laws that helped bring the sharks back 1971 - Clean Water Act

Southern California went from having some of the worst coastal water quality that existed in the U.S. – with primary treated raw sewage released one mile from shore – to having some of the best wastewater treatment in the world today. 1973 - Marine Mammal Protection Act

Marine mammals in U.S. waters have made an astounding recovery from the early 1900s, when most marine mammals in coastal California had been hunted to near extinction: for food or fur, or out of a belief that they competed with fishermen. 1994 - California Proposition 132

Passed by ballot measure in 1990, the California coastal gillnetting ban, which went into effect in 1994, has saved many animals from dying as bycatch, including marine mammals and several species of fish: white sharks, thresher sharks, leopard sharks, white sea bass, and more. 1996 - Sustainable Fisheries Act

After this extension of the Magnuson-Stevens Act, coastal fisheries reduced bycatch and became more sustainable. Fisheries recovered, not just in California, but in other parts of the country as well, rebuilding a torn food web from the bottom up. 1999 - Marine Life Protection Act

Today, California’s system of marine protected areas function as a network for conservation, sustainable fisheries, recreation, and education. They also help to rebuild southern California’s food web.

The Bight’s baby white sharks declined for a number of reasons, Lowe says: poor water quality, their decimation as gillnetting bycatch, and the near-extirpation of the prey that adult sharks rely on. Likewise, no single environmental law saved them. Instead, a suite of regulations enacted from the 1970s to the mid 1990s helped restore southern California’s coastal ecosystem enough for its white shark nursery to eventually start recovering. (See timeline).

In 1994, California passed a white shark fishing ban and a gillnet fishing ban, both of which protected baby white sharks. Since then, researchers have documented baby shark populations growing in the Bight. The sharks shape the Bight’s ecosystem, in turn. California’s seals and sea lions have rebounded so well under the Marine Mammal Protection Act, predators are needed to cull their populations and keep them healthy, Lowe says. Meanwhile, development projects such as marinas and residential buildings constructed in California’s estuaries have pushed stingrays out of their traditional habitats and into coastal waters, where the rays provide easy food for baby white sharks. In future, the sharks’ appetites might even make people safer: Stingrays injure beachgoers on California’s coast far more frequently than white sharks do, Lowe says, though he acknowledges that’s a hard argument to sell to a shark-phobic public.

“You hear about all the bad things we’re doing to the planet, to the ocean: the pollution, overfishing, global climate change,” Lowe says. Marine life faces continued threats, but the recovery of the shark population is a sign that humans are doing something right. “Maybe at a regional scale, but at least it’s a start.”