The Endangered Species Act turned 42 on Monday, marking over four decades of plant and animal conservation in the United States.
The act was signed into law on Dec. 28, 1973 by President Richard Nixon, who had urged Congress to expand the protection of imperiled species. Under the ESA, species deemed in danger of extinction qualify for strict protections, including bans or limitations on imports and hunting, as well as severe penalties for violation.
"Nothing is more priceless and more worthy of preservation than the rich array of animal life with which our country has been blessed," Nixon said after the law's passage. "It is a many-faceted treasure, of value to scholars, scientists, and nature lovers alike, and it forms a vital part of the heritage we all share as Americans."
There are now around 2,215 species listed as endangered or threatened under the act, including 650 found outside of the United States.
The most recent additions to the ESA, made earlier this month, were the two primary subspecies of the African lion, one of which is listed as "endangered" and the other as "threatened." The big cats' population numbers have plummeted to just half of what they were in 1993, with fewer than 20,000 remaining. The protections came after years of lobbying by conservation organizations and scientists, who warn that the animals could see a further 50 percent decline by 2050 without intervention.
Other species have fared well under the ESA's increased protections, such as the whitebark pine. The tree, which grows slowly and can live for more than a thousand years, has been devastated by climate change and an increase in mountain pine beetles. But Fish and Wildlife lowered the tree's protection priority earlier this month as the threat from insects has declined.
The ESA has been controversial in recent years, and the listing of some species has stalled due to partisan politics. For years, advocates called for the protection of the greater sage grouse, a bird resembling a turkey that lives in 11 Western states. Its habitat has been severely disrupted by oil and gas drilling, but some Republicans fought against a protection plan that they argued would have put those activities in jeopardy.
Eventually, the Obama administration decided to protect the sage grouse without ESA listing.
Republicans also called for a revamp of the law earlier this year, arguing that few listed species actually recover despite the massive government spending on them. But advocates have responded by pointing to examples such as the gray whale and the bald eagle, both of which have made notable recoveries.
Despite the objections, the Obama administration still seems interested in using the act to protect species that are most in need. There are 60 other species currently listed as candidates for ESA protection.
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