Shipping lanes shifted to protect whales

Changing the location of officially sanctioned shipping lanes into and out of Boston is not something that can be easily done - the consequences affect not just American vessels but international commerce. Shipping lanes are assigned by the International Maritime Organization (IMO), a part of the United Nations. But a Stellwagen Bank National Marine Sanctuary-led proposal to move the Boston lanes, also known as the Traffic Separation Scheme (TSS), to better protect feeding whales on Stellwagen Bank and in Massachusetts Bay won overwhelming support at an IMO meeting in late 2006. A less dangerous course was approved with a July 1, 2007 implementation date.

Using a 25-year database of more than a quarter of a million whale sightings from whale watch and whale research trips, sanctuary scientists showed that the heaviest concentrations of whales were located directly in the shipping lanes. The probability of future sightings in these areas was substantiated by ecological studies. Most of the whales target sand lance, a small schooling fish, which prefers the sandy sediments that predominate in areas with historically high whale sightings. For endangered North Atlantic right whales, which feed on small planktonic crustaceans, prevailing currents push their food into Cape Cod Bay and into the southern portion of the sanctuary where the lanes were located.

To mitigate the ship strike threat to great whales, the sanctuary, the National Oceanic & Atmospheric Administration’s Fisheries Service and the U.S. Coast Guard proposed that the lanes be narrowed and moved a few miles northward. Calculations indicated that for most vessels, the change would only add a few minutes to vessel transit times, but would dramatically reduce the potential of a ship hitting a whale — 81 percent for all whales (humpback, fin, minke, northern right) and 58 percent for the critically endangered North Atlantic right whale. The shipping industry also voiced their support for the northward shift of the lanes.

This potentially far-reaching marine mammal conservation effort was made possible by the donation of whale sightings data from the Provincetown Center for Coastal Studies, the Whale Center of New England and the North Atlantic Right Whale Consortium.

A version of this article appeared in Stellwagen Soundings, Summer 2007. Reprinted with permission.

© 2007 The Gulf of Maine Times