The Endangered Species Act:

The ESA was passed in 1973 with the goal of protecting and recovering populations of species in danger of extinction, as well as the habitats in which they live. Five threat factors are listed in Section 4(a) of the act as qualifications for listing:

(A) the present or threatened destruction, modification, or curtailment of its habitat or range; (B) overutilization for commercial, recreational, scientific, or educational purposes; (C) disease or predation;
 (D) the inadequacy of existing regulatory mechanisms; or (E) other natural or manmade factors affecting its continued existence.

The responsibilities for marine species’ protection are divided between the US Fish and Wildlife Service, which protects manatees, walruses, sea lions, and polar bears, and the National Marine Fisheries Services, which protects whales, dolphins, marine and anadromous fish, and other marine mammals. In total, 1,436 species are currently listed as either Endangered, where the species is in danger of extinction throughout its range, or Threatened, where the species is likely to become endangered soon. Section 4 of the ESA lists factors considered when deciding a species’ status, which include habitat destruction, overutilization, disease and predation, inadequacy of existing protective measures, and other natural or manmade factors that affect the survival of the species. Specifically, the species is protected by outlawing “take” of the protected species under Section 9 of the ESA. In addition to harming or killing the species, the definition of take also includes actions such as capture, pursuit, or harassment. Recovery plans identify population or habitat goals, and are to be developed and amended regularly in order to detail actions needed for species’ ultimate removal from the list.

Section 7 of the ESA requires consultations between federal agencies and the appropriate ESA facilitating agency in any case where federal action may impact listed species. Once the consultation is completed within the required 90-day time period, “the Secretary shall provide to the Federal agency and the applicant, if any, a written statement setting forth the Secretary’s opinion, and a summary of the information on which the opinion is based, detailing how the agency action affects the species or its critical habitat”. If the consultation and resulting Biological Assessment find that the action puts the listed species in jeopardy, either NMFS or FWS offers alternative options, which may include cancelation of the federal action. The ESA is also required to list Critical Habitat areas for listed species, which requires greater scrutiny of federal actions in these areas. Critical Habitats can be excluded, though, under the outcome of the Biological Assessment, and frequently are. Only situations where lack of Critical Habitat designation would cause the extinction of a species are mandated to implement this protection. The ESA also works with states and private landowners to develop conservation plan and programs under Section 6 of the Act, and administers species protection under the Convention on International Trade in Endangered Species of Wild Flora and Fauna.

Though the data is sometimes sparse, since its inception in 1973 the ESA has had multiple successes protecting threatened species from extinction. Measuring success against the goal of preventing extinction of endangered species, Schwartz found that up to 227 listed species were kept from extinction due to ESA listing from 1973-2003, while only 7 listed species went extinct due to relatively desperate circumstances at the time of listing. Comparing all species that became extinct during a similar time period, Schwartz similarly found that ESA listing improves chances of survival for chronically low-population species. In terms of recovery for protected species, once species became de-listed due to population changes, recoveries outnumbered extinctions by two-to-one, suggesting that ESA protections lifted most species out of danger and into sustainable population categories over time. Significantly, the ESA has been able to attain these outcomes while grappling with a noted, chronic lack of funding. The fact that the ESA has been as successful as it has in its current funding environment speaks to its effectiveness.