News & Events

An Introduction to the Endangered Species Act

(by Nisa Marks)

There are many good reasons to protect biodiversity. Species have intrinsic value, provide ecosystem services, and inspire medical breakthroughs. The US has a long history of laws to protect wildlife. The Endangered Species Act (ESA) is widely regarded as one of the most powerful. It was transformational in that it envisioned protecting any plant or wildlife species and not just species that were commonly hunted. Its protections have led to the recovery of iconic species like bald eagles and peregrine falcons, and protected hundreds of others from extinction.

So what does the Endangered Species Act (ESA) do? The ESA protects species through several mechanisms. It proscribes a process known as “listing” for a species to become formally recognized as endangered or threatened, and thereby given protections under the ESA. It is illegal to “take” a listed species, meaning a person or company cannot “harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect” any individual of a listed species without a permit. (It is also illegal to attempt to do any of those things.) The definitions of harass and harm are fairly broad, meaning that species are protected from both direct and indirect adverse effects. The ESA also has provisions that give limited protections to listed species’ habitats. Importantly, the ESA allows the U.S. Fish and Wildlife Service to grant money to the states for work to protect listed species. New Hampshire Audubon has received some of these funds through the New Hampshire Fish and Game Department to do surveys and help manage endangered birds in New Hampshire.

What does it mean to be an endangered species? By the time a species is listed, few enough individuals are left that the species is in danger of going extinct. Indeed, at least a dozen species are presumed to have gone extinct by the time they were added to the endangered species list. Because a species has to go through a lengthy review process before being added to the endangered species list, not all species that are in danger of going extinct are protected under the ESA. The monarch butterfly is a good example of such a species. It is considered an endangered species by the IUCN (whose reviews reflect the best available science on a species), but has not yet been listed under the ESA.

Piping Plover fledgling, by Walter Keane.

How successful is the ESA? The ESA is exceptionally successful at preventing extinction. Without the ESA, scientists estimate that at least 227 species would have gone extinct since its enactment (Scott et al. 2006; Schwartz 1999). Of species listed in the northeastern US, 93% are stable or moving towards recovery (Adkins 2016). That said, because of lack of funding and other issues only a few dozen species have been delisted with recovered populations, and many species face threats that require ongoing management in order to prevent negative impacts to their populations.

What kinds of activities does the ESA regulate? The ESA prohibits any action that “takes” (adversely affects) a listed species, unless that action is done with a permit. The ESA has permit processes that allow various actors, including federal and state agencies or private companies or individuals, to adversely affect individuals of a listed species, provided that actions are taken to avoid and minimize adverse effects. In practice, this means that few actions are prohibited. Instead, actors must figure out how to avoid and minimize impacts so that it is unlikely that a species will go extinct because of any one action.

How many species are listed? Nationally, there are more than 1,600 species on the endangered species list. Many more are in decline but not yet listed. Check out the table below to see which federally-listed species occur in New Hampshire.

What about species whose populations are declining? The ESA only protects species that are likely to go extinct in the foreseeable future. This means that many species whose numbers are declining do not qualify for the protections of the ESA. Some people liken being on the ESA to a species being in the emergency room. By the time a species is listed, it is usually in pretty bad shape. Emergency care is critical, but ideally we keep people out of the hospital through routine care and early interventions. The same is true in conservation. That is part of why New Hampshire Audubon does research on declining species, works to protect habitat, and educates people about how to protect birds, pollinators, and other species in our own backyards. The ESA creates an emergency room; other policies are still needed to protect species that are declining but still common enough to have a good chance at recovering.

What can I do? If you are a homeowner, following general biodiversity-friendly practices helps support healthy populations of birds, insects, and other biodiversity. Avoid use of herbicides and pesticides, plant native species, and consider devoting more of your property to wildlife habitat instead of lawn.  You can also donate to NH Audubon to support our scientific research and advocacy in support of endangered species.

Where can I learn more? The U.S. Fish and Wildlife Service (USFWS) and National Oceanic and Atmospheric Administration (NOAA) Fisheries administer the ESA. Broadly speaking, USFWS has jurisdiction over listed terrestrial and freshwater species and NOAA has jurisdiction over marine species. More information is available on their websites. New Hampshire Fish and Game also maintains information about federal and state-listed endangered species on their website.



Adkins, C. 2016. The US Endangered Species Act: a powerful tool to protect biodiversity (if we use it). Biodiversity 17(3): 101-103. DOI: 10.1080/14888386.2016.1206836

Schwartz M.W. 1999. Choosing the appropriate scale of reserves for conservation. Annual Revue of Ecology and Systematics 30:83–108.

Scott J.M., D.D. Goble, L.K. Scvancara, and A. Pidgorna. 2006. By the numbers. Pp.16-35 in D.D. Goble, J.M. Scott, and F.W. Davis, eds. The Endangered Species Act at Thirty: Renewing the Conservation Promise. Island Press, Washington, DC.

Federally Listed Threatened and Endangered Species in New Hampshire

U.S. Fish and Wildlife Jurisdiction

Common name Scientific name Status
Jesup’s milk vetch Astragalus robbinsii var. jesupii Endangered
Northeastern bulrush Scirpus ancistrochaetus Endangered
Small whorled pogonia Isotria medeoloides Threatened
Dwarf wedgemussel Alasmidonta heterodon Endangered
Rusty patched bumblebee Bombus affinis Endangered
Puritan tiger beetle Cicindela puritana Threatened
Karner blue Lycaeides melissa samuelis Endangered
Piping Plover Charadrius melodus Threatened
Red Knot Calidris canutus rufa Threatened
Roseate Tern Sterna dougallii dougallii Endangered
Northern long-eared bat Myotis septentrionalis Threatened
Canada lynx Lynx canadensis Threatened

National Oceanic and Atmospheric Administration Jurisdiction

Common name Scientific name Status
Shortnose Sturgeon Acipenser brevirostrum Endangered
Atlantic Sturgeon Acipenser oxyrinchus Endangered
Oceanic Whitetip Shark Carcharhinus longimanus Threatened
Giant Manta Ray Manta birostris Threatened
Loggerhead Turtle Caretta caretta Threatened
Green Turtle Chelonia mydas Threatened
Leatherback Turtle Dermochelys coriacea Endangered
Hawksbill Turtle Eretmochelys imbricata Endangered
Kemp’s Ridley Turtle Lepidochelys kempii Endangered
Sei Whale Balaenoptera borealis Endangered
Blue Whale Balaenoptera musculus Endangered
Fin Whale Balaenoptera physalus Endangered
North Atlantic Right Whale Eubalaena glacialis Endangered
Sperm Whale Physeter macrocephlus Endangered