This year marks the 50th anniversary of the Endangered Species Act (ESA), providing the opportunity to reflect on the progress made and the work ahead for protecting our nation’s endangered species and their habitats.
The ESA was signed into law by President Richard Nixon on December 28, 1973, and it was designed to protect and conserve imperiled species of plants and animals in the United States.
In its first 50 years, the ESA has been credited with saving 99% of listed species from extinction thanks to the collaborative actions of federal agencies, state, local and Tribal governments, conservation organizations and private citizens.
Some of the most notable successes include:
- The bald eagle was once on the brink of extinction but has since recovered thanks to the ESA.
- The California condor, which was down to just 22 individuals in the 1980s, has since been brought back to over 500 birds.
- The Florida panther rebounded from just 20 individuals in the 1970s to over 200 today.
- The American alligator population reached an all-time low in the 1950s but made a significant recovery and was removed from the list of endangered species in 1987.

The ESA has also been successful in protecting many other species, including the humpback whale, the grizzly bear, the whooping crane, and the desert tortoise.
The ESA currently protects 1,662 U.S. species and 638 foreign species but there are 142,500 animal and plant species on the Red List of the International Union for Conservation of Nature (IUCN) — 40,000 of which are “threatened with extinction.”
However, the ESA has also had its shortcomings. Some species, such as the ivory-billed woodpecker, have been declared extinct despite the best efforts of conservationists.
Other species, such as the northern spotted owl, have been caught in the crossfire of development and conservation, leading to conflict between landowners and environmental groups.
Despite its challenges, the ESA remains one of the most effective wildlife conservation laws in the world. It has helped to save hundreds of species from extinction and has raised awareness of the importance of protecting biodiversity.
“The Endangered Species Act is a vital law that has saved countless species from extinction,” said Lisa McCormick, an environmentalist from New Jersey. “It is essential that we continue to support and strengthen the ESA so that we can protect the plants and animals that make our planet so special.”
The ESA is facing new challenges in the 21st century, such as climate change and habitat loss.
However, with the continued support of conservationists and the public, McCormick said the Endangered Species Act can continue to be a powerful tool for protecting the variety and variability of life on Earth for generations to come.
Most conservationists believe that human activity has either produced or is on the cusp of producing a period called the Holocene extinction, also referred to as the sixth mass extinction after the “Big Five” mass extinction events that killed off a majority of existing species in Earth’s history.
The Sixth Extinction authors paleoanthropologist Richard Leakey and biochemist Roger Lewin estimated an annual extinction rate between 17,000 and 100,000 species.
More plants and animals than ever before are on a global list of threatened species, with the World Wildlife Fund Germany warning that more than 1 million species could go extinct within the next decades.
Among the animals most acutely threatened are the African forest elephant, whose population has declined by 86% within just 31 years. Polar bears made the list as well, as the rapid melting of pack ice in the Arctic Ocean is making it impossible for the animals to adapt. Experts estimate the Arctic Ocean could be completely ice-free in the summer of 2035.