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What's at Stake

Shipping’s Contribution to Climate Change and Air Pollution

Large vessels make a growing contribution to global warming and air pollution by burning dirty bunker fuel. Recent data estimates that one giant container ship produces as much cancer-causing and climate warming pollutants as 50 million cars; and just 15 of the behemoths may produce more pollution than all the world’s cars combined.

Reducing ship speeds can have a tremendous impact on reducing their greenhouse gas emissions. The International Maritime Organization of the United Nations (IMO) found that a 10 percent reduction in speed can result in a 28.2 percent reduction of CO2 emissions over a 20 year period. If changes in routing as well as hull shape and propulsion systems (both of which would also significantly reduce ocean noise pollution) were included, the reduction would total 46.4 percent.

Stopping Bad Vibes - Reducing Harmful Ocean Noise

Sound is king in the ocean – whales, dolphins, and fish depend on hearing to communicate, forage, find mates, detect predators, and maintain family and social groups.  Over the last 60 years, the level of low-frequency ocean noise has been steadily rising as a result of commercial shipping, energy exploration and human activities, all threatening the acoustic livelihood of marine life.

One of the most destructive, yet nearly invisible effects of this human-made noise is acoustic masking, which effectively drowns out the natural sounds in the ocean. The primary source of shipping noise is from propeller cavitation—tiny bubbles created and burst when the propeller turns—and the ship hull moving against the water which becomes noisier with higher speeds.  Scientists explain that a growing fog of ocean noise is shrinking the communication space, or the perceptual world, of whales and other marine life, compromising their ability to “see” with sound. In response to man-made noise whales have abandoned their preferred habitat and feeding areas, altered their surfacing and diving patterns, and the types, volumes, and timing of their calls. Blue whales, once capable of communicating across vast oceans, have seen their communication space shrink by about 90 percent today.

Our program is working to bring the experts together to characterize the noise impacts in our local marine sanctuaries, and to engage all of the ocean stakeholders in an effort to quiet these special marine places.

Preventing Whale Strikes

Recently, California has experienced a dramatic spike in whale strandings and deaths linked to collisions with large vessels.  In 2010 at least five whales fell victim to ship strikes in Bay Area waters within four months, including a 80- foot pregnant blue whale and her fetus, and a dead whale arriving into the Port of Oakland on a ship’s bow bulb.


In 2007 there were four confirmed blue whale fatalities from ship strikes in the Santa Barbara Channel, adjacent to the Channel Islands National Marine Sanctuary, more than in any previous year. Scientists believe many more whales are struck and killed by ships each year, yet go undetected because they sink at sea. Whales, dwarfed by gigantic cargo ships, are becoming mere speed bumps on the ocean superhighway.

The factors that contribute to ship strikes are still little understood but studies have determined that ships traveling faster than 10 knots are more likely to cause serious injury or death to whales caught in their path.  A 10 knot speed limit has been implemented along the Atlantic coast to protect critically endangered right whales and a similar voluntary speed limit is in place around the Channel Islands. Pacific Environment is working with its partners to refine and replicate similar measures in Northern California’s National Marine Sanctuaries and state MPAs.

Protecting the Ecology and Economy from Oil Spills


Just like cars, ships are prone to accidents and they sometimes spill oil when filling their giant tanks or off-loading crude cargo.  Two oil spills during fuel transfers at California ports in recent months spilled more than 1,300 gallons of toxic oil into local waters, forcing fisheries closures, killing seabirds, and contaminating sensitive habitat and beaches. By law, Californians are due the best achievable protection from the environmental impacts associated with oil spills. We’re working to insure that promise and by advocating for improved oil spill prevention and response to safeguard our invaluable marine environment and coastal economy.