Get access

The Marine Mammal Protection Act at 40: status, recovery, and future of U.S. marine mammals



This article is corrected by:

  1. Errata: Corrigendum for Ann. N.Y. Acad. Sci. 2013. 1286: 29–49 Volume 1296, 154–157, Article first published online: 28 August 2013

Address for correspondence: Joe Roman, Gund Institute for Ecological Economics, University of Vermont, Burlington, VT 05405.


Passed in 1972, the Marine Mammal Protection Act has two fundamental objectives: to maintain U.S. marine mammal stocks at their optimum sustainable populations and to uphold their ecological role in the ocean. The current status of many marine mammal populations is considerably better than in 1972. Take reduction plans have been largely successful in reducing direct fisheries bycatch, although they have not been prepared for all at-risk stocks, and fisheries continue to place marine mammals as risk. Information on population trends is unknown for most (71%) stocks; more stocks with known trends are improving than declining: 19% increasing, 5% stable, and 5% decreasing. Challenges remain, however, and the act has generally been ineffective in treating indirect impacts, such as noise, disease, and prey depletion. Existing conservation measures have not protected large whales from fisheries interactions or ship strikes in the northwestern Atlantic. Despite these limitations, marine mammals within the U.S. Exclusive Economic Zone appear to be faring better than those outside, with fewer species in at-risk categories and more of least concern.