San Francisco Bay Shipping Lanes Narrowed to Protect Whales

Cargo ships coming into San Francisco Bay must now follow new, narrower shipping lanes as they approach the Golden Gate. The change is designed to protect whales off the coast, as increasing numbers have been struck and killed by large ships.

“The problem is getting worse and that’s to be expected,” said John Calambokidis, a biologist with the Cascadia Research Collective who has tracked whale strikes. “The ships are getting larger, more numerous and faster.”

According to federal scientists, at least 20 whales have been killed and 10 whales have been injured or possibly killed off the California coast since 1988. But many believe most whale strikes go undetected.

“Most ships that come in with a whale wrapped around their bow are often unaware of it,” said Calambokidis. “We suspect many of these strikes are unknown to these larger ships, with most of the whales not being discovered or sinking.”

The cold waters outside of San Francisco Bay provide a rich feeding ground for humpback and blue whales. Gray whales are often seen close to shore as they migrate through in the winter and spring. “We’re particularly concerned about blue whales not only because of the number of ship strikes, but also because blue whales have not been showing recovery off the West Coast,” Calambokidis said.

The new rules extend the three main shipping lanes to San Francisco Bay, so ships are funneled into smaller zones as they approach shore.

“It might add a slight amount of time and cost to the ship transit but we still think they’re good choices to make,” says John Berge with the Pacific Merchant Shipping Association. “Nobody on a ship wants to hit anything, least of all a whale, just as nobody driving down a highway wants to hit anything.”

“I would really call them modest,” said Calambokidis. “While I think they represent progress, we also have to recognize that they were the easiest first steps. This might reduce the incidence of ships strikes in the tens of percent, but they won’t eliminate it.”

Dynamically Changing Shipping Lanes with Help From Citizen Science

While the new changes are year-round, federal official with NOAA and the Coast Guard are also hoping to create dynamically changing shipping lanes, based on real-time whale tracking.

These “dynamic management areas” would go into effect when whales are spotted in a shipping lane. A temporary speed limit would go into effect, slowing ships down and encouraging them to use the other approaches to the Bay.

To gather whale-tracking data, the federal marine sanctuaries off the coast are teaming up with non-profits to create a citizen science app called “Spotter,” available soon online. They’re asking whale watching boats, recreational boats, commercial fishermen and members of the public to report when they spot whales offshore. The data will feed into WhaleAware.org, managed by PRBO Conservation Science.

“We’re testing this first year to see if we get enough data,” says Michael Carver of Cordell Bank National Marine Sanctuary. NOAA scientists are also training cargo ship crews to use the app. “It’s really in their best interest,” Carver says. “It’s a temporary speed limit, but not a permanent reduction.”