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Threatened & Endangered Marine Animal Species

Regulatory Agencies, Information, & Terminology

United States Species of Concern:

An informal term referring to a species that might be in need of conservation action. This may range from a need for periodic monitoring of populations and threats to the species and its habitat, to the necessity for listing as threatened or endangered. Such species receive no legal protection and use of the term does not necessarily imply that a species will eventually be proposed for listing.

United States Threatened species:

An animal or plant species likely to become endangered within the foreseeable future throughout all or a significant portion of its range.

United States Endangered species:

Any animal or plant species which is in danger of extinction throughout a significant portion of its range.

Endangered Species Preservation Act (1966): Established in the United States to protect species facing possible extinction.  Addresses only native species and protection is limited.

Endangered Species Conservation Act (1969): Composed by the Departments of the Interior, Agriculture, & Defense to prevent mass extinctions of certain species.  The use of endangered species by humans for food, fur, and other commercial uses was outlawed by this act and by the Marine Mammal Protection Act of 1972.

Marine Mammal Protection Act (1972): USA law that outlawed the use of endangered marine mammal species by humans for food, fur, and other commercial uses.  Also stipulated that a species can be defined as “depleted”, meaning that its population numbers have dropped lower than the optimum sustainable population (OSP). The OSP is determined by whether the animals are reproducing in a healthy number that corresponds to the carrying capacity of the environment.  Marine animals considered depleted are the North Atlantic Coastal bottlenose dolphin, the Eastern spinner dolphin, North Pacific fur seal, Northeastern spotted dolphins, and the Cook Inlet beluga whale.

Convention on International Trade in Endangered Species (CITES) of Wild Fauna and Flora (1973):
Developed to regulate or prohibit international commerce of plant and animal species believed to be harmed by or that may be harmed by international trade. The authority to implement this is under section 8 of the Endangered Species Act.

The Endangered Species Act (1973): USA law that is intended to provide a means to conserve the ecosystems upon which endangered and threatened species depend and provide programs for the conservation of those species, thus preventing extinction of plants and animals. The law is administered by Interior Department's Fish and Wildlife Service ( and Commerce Department''s National Oceanic and Atmospheric Administration Fisheries Service (, depending on the species.

International Union for Conservation of Nature and Natural Resources (IUCN): Headquartered in Gland, Switzerland, the IUCN provides general conservation categories of extinct, extinct in the wild, critical or critically endangered, endangered, vulnerable and secure, or low risk for different species throughout the world.  The IUCN Red List ( provides a general conservation status for different species and indicates how many exist, an increase or decrease in numbers, how well they are reproducing, and if the population faces potential threats.

IUCN Conservation Categories

Endangered and threatened species chart

The regulatory agencies, information and terminology provided are based primarily upon United States laws, however this page is still in development.  Suggestions for regulatory information from other countries are requested and should be sent to


Threatened or Endangered Marine Mammals in the United States

Common Name Genus Species Status
Blue Whale Balaenoptera musculus Endangered
Bowhead Whale  Balaena  mysticetus Endangered
Caribbean Monk Seal  Monachus  tropicalis Endangered/Extinct
Guadalupe Fur Seal  Arctocephalus  townsendi Threatened
Hawaiian Monk Seal  Monachus  schauinslandi Endangered
Finback Whale  Balaenoptera  physalus Endangered
Humpback Whale  Megaptera  novaeangliae Endangered
Killer Whale (Southern pop.)  Orcinus  orca Endangered
Northern Sea Otter  Enhydra  lutris kenyoni Threatened
Polar Bear  Ursus  maritimus Threatened
Right Whale  Balaena  glacialis/australis Endangered
Sei Whale  Balaenoptera  borealis Endangered
Southern Sea Otter  Enhydra  lutris nereis Threatened
Sperm Whale  Physeter  catodon (macrocephalus) Endangered
Steller Sea Lion  Eumetopias  jubatus Endangered (Western pop.);
Threatened (Eastern pop.)
West Indian Manatee  Trichechus  manatus Endangered


Threatened or Endangered Marine Reptiles in the United States

Common Name Genus Species Status
Green Sea Turtle Chelonia mydas Endangered (FL & Mexico);
Threatened (Elsewhere)
Hawksbill Sea Turtle Eretmochelys imbricata Endangered
Kemp''s Ridley Sea Turtle Lepidochelys  kempii- Endangered
Leatherback Sea Turtle Dermochelys coriacea Endangered
Loggerhead Sea Turtle Caretta caretta Threatened
Olive Ridley Sea Turtle Lepidochelys olivacea Endangered (Mexico)
Threatened (Elsewhere)