Vessel Speed Reduction to Protect Whales

Looking down on container ship with hundreds of long containers of various colors

Container ships are of the largest vessels that transit through the sanctuaries. Credit: Jess Morton/NOAA

Informed by the advisory council recommendations, Greater Farallones and Cordell Bank national marine sanctuaries, in collaboration with the United States Coast Guard, implemented a vessel speed reduction (VSR) program requesting vessels 300 GT (gross tons) and larger to reduce speed to 10 knots (11.5 mph) maximum speed in the shipping lanes approaching and leaving San Francisco Bay, to reduce fatal collisions between ships and whales.

Vessel speed is a contributing factor in the occurrence and severity of vessel collisions with large whale species (Vanderlaan and Taggart 2007), and impact forces involved in a collision increase with increasing vessel speed (Conn and Silber, 2013). In 2008, NOAA issued mandatory vessel speed restrictions of 10 knots or less for all vessels 65 feet and greater in length along the U.S. eastern seaboard in designated seasonal management areas. (NOAA Vessel Speed Restrictions)

Starting in 2015, Greater Farallones and Cordell Bank National Marine Sanctuaries requested seasonal vessel speed reductions from May 1 through November 15 to slow vessels during the period of peak whale abundance in the region when the threat of vessel strikes is the highest. In 2022, upon analysis of data that showed whales are staying in the region for longer periods of time, the vessel speed reduction request was extended from May 1-December 15. Greater Farallones and Cordell Bank National Marine Sanctuaries extended the vessel speed reduction season in coordination with Channel Islands National Marine Sanctuary. It was important to coordinate with Channel Islands National Marine Sanctuary to have consistent dates for the industry for planning purposes. NOAA's Office of National Marine Sanctuaries distributes this 10-knot speed request through published and broadcast local notice to mariners, NOAA hourly broadcasts on marine band weather radio, and direct communication with the maritime community through email and letters to the shipping industry. This includes bar pilots, Pacific Merchant Shipping Association, West Coast ports, commercial operators, and other government organizations. There has been a steady increase in cooperation from the shipping industry each year.

A container ship on the ocean

Reducing speed to 10 knots of less drops air emissions and reduces the risk of a fatal ship strike on a whale. Credit: Lottie Keenan, Island Packers

The sanctuaries annually recognize shipping firms with high levels of cooperation in reducing speed in the traffic lanes. This is done publicly, through news media and advertising in international and regional shipping industry publications, and helps foster a growing partnership between commerce and conservation, leading to increased protection for endangered whales. At the end of the season, NOAA's Office of National Marine Sanctuaries sends summary statistics about VSR cooperation to shipping companies with vessels over 300 GT using the traffic lanes in and out of San Francisco Bay. In 2018 the end-of-season outreach program expanded to Channel Islands National Marine Sanctuary. Sanctuaries report vessel speed reduction progress at public Sanctuary Advisory Council meetings. View the Greater Farallones National Marine Sanctuary Advisory Council updates here: 2014, 2015, 2018, 2019, 2022.

Partnership with Air Districts to Slow Vessels

WhaleTail awards

Sapphire award winning companies who showed a high level of cooperation with NOAA sanctuaries vessel speed reduction program. Credit: Jess Morten/NOAA

In addition to reducing the risk of lethal ship strikes to whales, VSRs also reduce air pollution. NOAA's Office of National Marine Sanctuaries, in collaboration with California air control districts and partnering foundations, conducts the "Protecting Blue Whales and Blue Skies" incentive program from May through November which offers container and car carrier lines financial awards based on the percent of distance traveled by their vessels through the VSR zones at 10 knots or less. The program encourages the fastest ships to travel more slowly, producing less air pollution and reducing the risk of lethal ship strikes. The VSR program contributed toward the goal adopted by the International Maritime Organization in April 2018 to reduce the total annual GHG emission by at least 50% by 2050 compared to 2008. "A modest 10% speed reduction across the global fleet has been estimated to reduce overall GHG emissions by around 13% (Faber et al., 2017) and improve the probability of meeting GHG targets by 23% (Comer et al., 2018)" (Leaper 2019).

Ships transiting the California coast generate nitrogen oxides (NOx, a component of smog), sulfur oxides (SOx), particle pollution, and greenhouse gases. For example, in 2020, 16 shipping companies slowed to 10 knots or less for a total of 181,306 nautical miles, which reduced 748 tons of smog-forming nitrogen oxides (NOx) and 24,258 tons of GHGs. The typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year. In 2020 the VSR program removed the equivalent of 5,273 smog-forming cars from the road.