Protecting Endangered Whales in the Stellwagen Bank National Marine Sanctuary

Stellwagen Bank National Marine Sanctuary

The Stellwagen Bank sanctuary is a federally designated 842-square-mile marine protected area off the coast of Massachusetts and hosts some of the largest aggregations of endangered whales along the eastern seaboard. The Boston Traffic Separation Scheme (TSS), established by the U.S. Coast Guard under the Ports and Waterways Safety Act, crosses the sanctuary bringing thousands of annual vessel transits through it. As a result, the sanctuary is a hot spot for collisions between whales and ships.

The goal of the National Oceanic and Atmospheric Administration (NOAA) was to reconfigure the TSS to reduce the co-occurrence of ships and whales, minimizing collisions. ArcGIS software pinpointed high-use whale areas. Bathymetric data and current models helped identify whale foraging habitat, providing additional support for the identified distribution patterns. Working with industry for six months, NOAA used an iterative approach to identify a lane shift configuration that minimized the number of whales in the TSS while also minimizing impacts to industry. Ultimately, the reconfigured TSS consisted of a 12-degree northerly rotation of the eastern end and a narrowing of the TSS by 1 nautical mile (from 5 to 4).

Baleen whale sightings were reduced by 81 percent and right whale sightings by 58 percent while industry transit times increased by only 9 to 22 minutes. The new route also decreased the overlap between ships using the TSS and commercial fishing and whale watch vessels, which increased maritime safety. NOAA worked with various organizations to implement the new route.

Courtesy of NOAA.

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