Nearly two dozen species are being taken off the endangered species list because they are extinct, the U.S. Fish and Wildlife Service said Monday. 

Most of the species were listed under the Endangered Species Act in the 1970s or 1980s and were very low in numbers or likely already extinct at the time of listing. In the years since, "rigorous reviews of the best available science" have been conducted to determine whether the animals are extinct. 

"Federal protection came too late to reverse these species' decline, and it's a wake-up call on the importance of conserving imperiled species before it's too late," Service Director Martha Williams said.

Scientists in 2019 warned that worldwide, 1 million species of plants and animals were at risk of extinction. There are more than 1,300 species listed as either endangered or threatened in the United States under the Endangered Species Act. The 21 species being removed include one mammal, 10 types of birds, two species of fish and eight types of mussels. Eight of the 21 species were found in Hawaii. 

"The 21 species extinctions highlight the importance of the ESA and efforts to conserve species before declines become irreversible," the government agency wrote in its announcement. "The circumstances of each also underscore how human activity can drive species decline and extinction by contributing to habitat loss, overuse, and the introduction of invasive species and diseases."

The Fish and Wildlife Service had first proposed delisting the species in September of 2021. At the time, the agency proposed removing 23 species from the Endangered Species Act. In the years since, the Fish and Wildlife Service withdrew the delisting proposal for one species, a type of Hawaiian herb. It's also continuing to review information for another, the ivory-billed woodpecker.

While some species are removed from the Endangered Species Act because they're considered extinct, others are delisted because their populations have rebounded. According to the agency, more than 100 species of plants and animals have been delisted based on recovery or reclassified from endangered to threatened based on improved conservation status.

"The ultimate goal is to recover these species, so they no longer need the act's protection," Williams said.

Aliza Chasan

Aliza Chasan is a digital producer at 60 Minutes and CBS News.

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