The US Endangered Species Act (ESA) turns 50 in 2023. While it has been highly effective at saving endangered species across that time, unfortunately, it has not been enough to save all of them. The Fish and Wildlife Service has announced that 21 species have been removed from the act and not for a good reason. These 21 species have been lost to extinction. 

Among the species lost from the list, including plants and animals, is the only mammal of the 21 species – the Little Mariana fruit bat (Pteropus tokudae) from Guam. Alongside it, ten bird species have been lost, eight of them from the state of Hawaii. Two fish species, including the San Marcos gambusia (Gambusia georgei), which only lived in the San Marcos River, have also been declared extinct, as well as several species of mussels. 

“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,” said Service Director Martha Williams in a statement.

The conservation organization The Centre for Biological Diversity suggested in a statement that the cause of the loss of so many Hawaiian bird species was related to habitat destruction due to agricultural development. Climate change has also allowed mosquitoes to spread into new regions, threatening more already vulnerable species.

The delisting proposal contained 23 species; however, the Phyllostegia glabra var. lanaiensis, a herb in the mint family, was found to have new potentially suitable habitats and so was not classified as extinct.

The proposal also included the somewhat infamous ivory-billed woodpecker (Campephilus principalis), which had its last most widely accepted sighting in 1944, although it has since been claimed to still exist in the forests of Louisiana. The Fish and Wildlife Service announced that “although the delisting proposal included the ivory-billed woodpecker, the Service will continue to analyze and review the information before deciding whether to delist the ivory-billed woodpecker.” 

The 21 species in the act that have been declared extinct were largely added in the 1970s and 80s; the Fish and Wildlife Service suggested that it is highly likely the species were in extremely low numbers at that time, or already extinct at the time of the listing. 

The ESA has been credited with saving 99 percent of the listed species from extinction. More than 100 species of flora and fauna have been delisted for the positive reason of being reclassified based on improved conservation status. Many more species are being recovered and populations are increasing thanks to those who work to protect these habitats and species. 

“As we commemorate 50 years of the Endangered Species Act this year, we are reminded of the Act’s purpose to be a safety net that stops the journey toward extinction. The ultimate goal is to recover these species, so they no longer need the Act’s protection,” finished Williams.