Glossary: Marine Mammal Protection Act

Harassment under the Marine Mammal Protection Act

Under the 1994 Amendments to the Marine Mammal Protection Act, harassment is statutorily defined as, any act of pursuit, torment, or annoyance which—

• Has the potential to injure a marine mammal or marine mammal stock in the wild (known as Level A harassment); or

• Has the potential to disturb a marine mammal or marine mammal stock in the wild by causing disruption of behavioral patterns, including, but not limited to, migration, breathing, nursing, breeding, feeding, or sheltering but which does not have the potential to injure a marine mammal or marine mammal stock in the wild (known as Level B harassment).

Marine Mammal Stock

A stock is defined by the Marine Mammal Protection Act, as a group of marine mammals of the same species or smaller taxa in a common spatial arrangement, that interbreed when mature. See a list of the marine mammal stocks NOAA protects under the MMPA.

Strategic and Depleted Stocks

A strategic stock is defined by the Marine Mammal Protection Act as a marine mammal stock—

• For which the level of direct human-caused mortality exceeds the potential biological removal level;

• Which, based on the best available scientific information, is declining and is likely to be listed as a threatened species under the Endangered Species Act within the foreseeable future; or

• Which is listed as a threatened or endangered species under the ESA, or is designated as depleted under the MMPA.

A depleted stock is defined by the MMPA as any case in which—

• The Secretary of Commerce, after consultation with the Marine Mammal Commission and the Committee of Scientific Advisors on Marine Mammals established under MMPA title II, determines that a species or population stock is below its optimum sustainable population;

• A State, to which authority for the conservation and management of a species or population stock is transferred under section 109, determines that such species or stock is below its optimum sustainable population; or

• A species or population stock is listed as an endangered species or a threatened species under the ESA.

NOAA Fisheries prepares marine mammal stock assessment reports to track the status of marine mammal stocks.

Take and Incidental Take Under the Marine Mammal Protection Act

Take as defined under the MMPA means "to harass, hunt, capture, or kill, or attempt to harass, hunt, capture, or kill any marine mammal" (16 U.S.C. 1362)

It is further defined by regulation (50 CFR 216.3) as “to harass, hunt, capture, collect, or kill, or attempt to harass, hunt, capture, collect, or kill any marine mammal. This includes, without limitation, any of the following:

• The collection of dead animals, or parts thereof.

• The restraint or detention of a marine mammal, no matter how temporary.

• Tagging a marine mammal.

• The negligent or intentional operation of an aircraft or vessel.

• The doing of any other negligent or intentional act which results in disturbing or molesting a marine mammal.

• Feeding or attempting to feed a marine mammal in the wild.”

An incidental take is an unintentional, but not unexpected, taking.

Marine Mammal Stranding

The term "stranding" as defined in the MMPA means an event in the wild in which—

A marine mammal is dead and is—

• On a beach or shore of the United States; or

• In waters under the jurisdiction of the United States (including any navigable waters)

Or

A marine mammal is alive and is—

• On a beach or shore of the United States and unable to return to the water

• On a beach or shore of the United States and, although able to return to the water, is in need of apparent medical attention

• In the waters under the jurisdiction of the United States (including any navigable waters), but is unable to return to its natural habitat under its own power or without assistance.

A stranded marine mammal becomes a specimen under the jurisdiction of the Secretary of Commerce or authorized representatives. NOAA Fisheries’ Marine Mammal Health and Stranding Response Program coordinates a network of responders in all coastal states to respond to marine mammal strandings.

Minimum Population Estimate

A minimum population estimate is defined by the MMPA as an estimate of the number of animals in a stock that—

• Is based on the best available scientific information on abundance, incorporating the precision and variability associated with such information; and

• Provides reasonable assurance that the stock size is equal to or greater than the estimate.

NOAA publishes annual Stock Assessment Reports that include the minimum population estimate. 

Optimum Sustainable Population

An optimum sustainable population is defined by the MMPA section 3(9), with respect to any population stock, as the number of animals which will result in the maximum productivity of the population or the species, keeping in mind the carrying capacity of the habitat and the health of the ecosystem of which they form a constituent element. (16 U.S.C. 1362(3)(9))

Optimum sustainable population is further defined by Federal regulations (50 CFR 216.3) as a population size which falls within a range from the population level of a given species or stock which is the largest supportable within the ecosystem to the population level that results in maximum net productivity. Maximum net productivity is the greatest net annual increment in population numbers or biomass resulting from additions to the population due to reproduction and/or growth less losses due to natural mortality.

Potential Biological Removal (PBR) Level

The potential biological removal (PBR) level is defined by the MMPA as the maximum number of animals, not including natural mortalities, that may be removed from a marine mammal stock while allowing that stock to reach or maintain its optimum sustainable population. The PBR level is the product of the following factors—

• The minimum population estimate of the stock;

• One-half the maximum theoretical or estimated net productivity rate of the stock at a small population size; and

• A recovery factor of between 0.1 and 1.0.

NOAA publishes annual Stock Assessment Reports that include the potential biological removal level for marine mammal stocks.

Federal Register

The Federal Register (FR) is the official daily journal of the United States Government and contains rules, proposed rules, and notices published by the various federal agencies. When we publish a final rule, proposed rule, or notice in the Federal Register, we refer to the document citation (for example: 81 FR  62259) which identifies the volume number (e.g, 81) and page number (e.g., 62259) on which the document begins.

Code of Federal Regulations

The Code of Federal Regulations (CFR) contains regulations created by various federal agencies to support and explain Federal statutes. Both the U.S. Fish and Wildlife Service and NOAA Fisheries have created wildlife and fisheries regulations to support and clarify sections of the Marine Mammal Protection Act and the Endangered Species Act. The wildlife and fisheries regulations pertaining to marine mammals and endangered species can be found in 50 CFR 1 – 599.