A working group tasked with reducing the risk of lethal ship strikes to endangered whales recently published recommendations to slow ship traffic in waters in the National Marine Sanctuaries and waters surrounding the San Francisco Bay. The group, composed of conservationists, scientists, and representatives of the fishing and shipping industries, recommended a year-round, voluntary speed reduction within the Greater Farallones and Cordell Bank National Marine Sanctuaries, as well as the northern part of the Monterey Bay National Marine Sanctuary.
The report recommends slowing the speed of ships to less than 10 knots along the of coast from Point Arena in Mendocino County to Pigeon Point in San Mateo County in order to reduce ship strikes by 50% along the North central coast.
Ship strikes and fatalities of whales are unfortunately not rare events in the busy shipping lanes approaching the Bay. Ships converging on the Bay overlap feeding grounds for many species of great whales, including blue, fin, humpback and California gray whales. From 2011 to 2021 an average of 10 whales a year were officially recorded as being struck by vessels along the West Coast according to the National Oceanic and Atmospheric Administration. The list includes humpback, gray, minke and sei whales in addition to endangered blue and fin whales.
However, the non-profit research group Point Blue Conservation Sciences, estimates as many as 83 endangered whales are killed by ships on the West Coast each year. The exact number is unknown because often dead whales sink and are unreported, or wash ashore in a severely decomposed state making it difficult to confirm the cause of death.
Strandings of dead whales along Bay Area beaches has increased in recent years, up from 11 in 2018 to 21 in 2021, according to the Marine Mammal Center in Sausalito. Along with entanglement in fishing gear and malnutrition, it is believed that ship strikes are a leading cause of whale death.
Since 2013, there has been a voluntary vessel speed reduction to 10 knots (11.5 mph) in place for large ships in the three shipping lanes that converge to the main shipping channel eight miles off the Golden Gate. Ships typically speed up as they exit the Bay and radiate into whale habitat once they exit the main shipping channel. The provisions only last between May to November, during the whale migration season. It will not protect residents, or whales that arrive early or stay late in the rich feeding grounds of the National Marine Sanctuaries.
In a petition to the National Marine Fisheries Service and a lawsuit against the U.S. Coast Guard and NMFS, the Center for Biological Diversity is calling for mandatory speed limits in shipping lanes at the Port of Los Angeles and San Francisco Bay. The number of whales killed each year exceeds what the populations can withstand and still recover the group argues.
Around 3000 ships enter the bay each year with an average of eight- ten large ships each day. The large demand for imported goods in the USA will continue to place these gentle giants in the path of container ships. Nearshore strikes in shipping lanes and collisions in the Bay are a growing concern as some grey whales, and especially juvenile humpback whales, are feeding in the Bay Area waters year-round. This April, a California Grey whale washed up dead in the shipping lanes near Alameda, with evidence it died from a ship strike. It is hopeful that we can co-exist as a functional commercial port, National Marine Sanctuary and safe harbor for whales in the San Francisco Bay if shipping companies adhere to the speed recommendations.
Shark Stewards leads wildlife trips into the Greater Farallones National Marine Sanctuary out to the Farallon Islands each fall, and records whales in and near the shipping lanes, and ship speeds.