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Marine Mammal Protection Act And Litigation Highlights

Dolphins.  Courtesy of USDA.


Passage of Act

Congress passed the Marine Mammal Protection Act (MMPA) of 1972 to address concerns that certain species and population stocks of marine mammals could be in danger of extinction or depletion as a result of human activities. The MMPA’s primary objective is to:

  • prevent marine mammal species and stocks from diminishing to the point that they are no longer a significant functioning part of their ecosystems and;
  • to restore diminished species and stocks to their optimum sustainable populations.

Adult and juvenile Steller sea lions.  Courtesy of NOAA.As part of this goal, the MMPA emphasizes the need to protect essential habitats, including rookeries, mating grounds, and other areas of significance for marine mammals from the adverse effects of human actions. The Secretary of the Department of the Interior is responsible for implementing the MMPA with respect to polar bears and walruses, while the Secretary of the Department of Commerce is responsible for implementing the MMPA with respect to whales, dolphins, porpoises, seals, sea lions, and other cetaceans and pinnipeds, except walruses.

Initial Litigation

NOAA “Observers”. One of Congress’ concerns in passage of the MMPA was the tuna fishing industry’s practice of setting nets around schools of porpoise in order to encircle the tuna swimming beneath. MMPA regulations prohibited this practice, which had generated a great deal of public concern, creating the market for “dolphin-safe” tuna.

Early litigation on these regulations focused on the requirement that tuna fishing vessels carry National Oceanic and Atmospheric Administration (NOAA) “observers” for the duration of the fishing trip to document compliance with the prohibition. Violations could lead to criminal penalties, and fishermen challenged the requirement as a warrantless search in violation of the Fourth Amendment. Finding that the observer program was critical to implementation of the MMPA’s protections in a closely regulated industry, courts upheld the requirement.

Mother-calf pair of killer whales in the Ross Sea. Courtesy of U.S. Antartic Program.MMPA “Permitting” and the “Taking” of Marine Animals. More recent MMPA litigation has focused on MMPA permitting. The MMPA imposes a general moratorium on the “taking” of marine mammals. The moratorium applies to all marine mammals, without regard to the relative scarcity or abundance of a particular species or population stock.

This moratorium on “taking” prohibits harassing, hunting, capturing, or killing a marine mammal, or attempting to do any of these things. However, the MMPA provides a number of exceptions to the moratorium, including:

  • exceptions for commercial fishing, scientific research, public display, photography, and;
  • an “incidental taking” exception that allows citizens of the United States who engage in a “specified activity” within a “specified geographical region” to request authorization for the “incidental, but not intentional” taking of “small numbers of marine mammals of a species or population stock” for a period of no more than five consecutive years.

Under the exception for incidental taking, the Fish and Wildlife Service (FWS) or the National Marine Fisheries Service (NMFS) must find that the total taking over the five-year period will have a “negligible impact” and will not adversely affect the availability of the marine mammal species or stock for subsistence use by Alaskan natives. Congress added this exception for “incidental taking” in 1981, recognizing that a variety of important human activities may unintentionally and inadvertently “take” marine mammals.

The agency must also issue regulations identifying permissible methods of taking and ways to mitigate the impact of the specified activity. The regulations make the necessary statutory findings and establish the framework for take authorization, but take is actually authorized through the issuance of letters of authorization.

FWS and NMFS have authorized the taking of marine mammals through the issuance regulations and letters of authorization for a number of activities, including sea and space shuttle activities at Vandenberg Air Force Base in California, and several of these authorizations have been the subject of litigation.



Updated May 9, 2023