Animals Endangered Species 10 U.S. Ecosystems Saved by Endangered Species By Melissa Breyer Melissa Breyer Twitter Editorial Director Hunter College F.I.T., State University of New York Cornell University Melissa Breyer is Treehugger’s editorial director. She is a sustainability expert and author whose work has been published by the New York Times and National Geographic, among others. Learn about our editorial process Updated October 10, 2021 Many acres of Lake Erie and its surrounding shoreline gained federal protection to conserve the declining Lake Erie water snake, and the whole lake ecosystem benefited as a result. Steven_Kriemadis / Getty Images Share Twitter Pinterest Email Animals Wildlife Pets Animal Rights Endangered Species The Endangered Species Act was signed in 1973, providing agency for the conservation of vulnerable species. As a bonus, their habitats—whether an underwater kelp forest, an aboveground pine forest, or a tropical island—receive protection from the law as well. A 2016 report from the Center for Biological Diversity revealed just how much the Endangered Species Act has benefited and decidedly saved some magical places. According to co-authors Jamie Pang and Brett Hartl, the Endangered Species Act has not only prevented 99% of protected plant and animal species from going extinct, but it has also helped revitalize some of the U.S.'s most remarkable forests, plains, deserts, and oceans, from the kelp forests off the West Coast to the Southeast's longleaf pine ecosystem. Here are 10 places the report says have been saved by the Endangered Species Act. 1 of 10 Pacific Kelp Forests (West Coast) Cameron D Smith / Getty Images Sea otters are a keystone species, one whose decline can quickly unravel an entire ecosystem. This was proven by their plummeting population, much attributed to the fur trade, along the coast of California and Oregon prior to being listed as threatened under the Endangered Species Act in 1977. As sea otters became more sparse, sea urchins (a common food source) became more plentiful, pillaging the kelp forests on which sea lions, whales, and sea snails relied. The shoreline also took a hit from this as it became more susceptible to erosion and greenhouse gases without the protective seagrasses. But in the 40 years following their adoption into the Endangered Species Act, the southern sea otter population almost tripled. As a result, kelp forests began to recover (if only briefly—they're in a major crisis). One 2020 study said sea otter recovery could be worth as much as $53 million per year. 2 of 10 Hakalau Forest National Wildlife Refuge (Hawaii) Timothy Hearsum / Getty Images The Hawaiian islands are some of the U.S.'s most biodiverse regions, but also a hotbed of endangered species, thanks much to scores of invasive species. The introduction of rats, cats, cane toads, mongooses, goats, pigs, and a melange of other non-native plants and animals have helped diminish Hawaiian species. The Hakalau Forest National Wildlife Refuge on Hawaii’s Big Island was established in 1997 and is completely fenced off to control the feral pig population, therefore serving the extinct-in-the-wild `alalā, or Hawaiian crow, notes the Center for Biological Diversity report. Now, the thriving refuge plays home to many endangered species, like the Hawaii `akepa, Hawaii creeper, `akiapōlā`au, the `io (Hawaiian hawk), and the ōpe`ape`a (Hawaiian hoary bat). 3 of 10 San Bernardino National Wildlife Refuge (Arizona) Ron and Patty Thomas / Getty Images This 2,300-acre refuge was established in the early 1980s for the protection of four endangered fish species endemic to the Río Yaqui: the Yaqui topminnow, Yaqui chub, Yaqui beautiful shiner, and Yaqui catfish. The refuge also protects the remaining parts of the San Bernardino ciénega, an integral marsh that serves as a corridor for migrating species. Without the marsh, many struggling species of fish, birds, mammals, bees, butterflies, and amphibians would not be able to survive the desert. In the meantime, other species, like the threatened Chiricahua leopard frog, threatened Mexican garter snake, and endangered lesser long-nosed bat, have also been given a second chance thanks to the fish conservation efforts. 4 of 10 Balcones Canyonlands National Wildlife Refuge (Texas) Mark Bonica / Flickr / CC BY 2.0 Created in 1992 to protect two endangered songbirds, the golden-cheeked warbler and black-capped vireo, the Balcones Canyonlands National Wildlife Refuge near Austin also serves to protect some of the last remaining Ashe juniper and oak woodlands in the state. Prescribed fire has helped control invasive plant species, and the elimination of cattle grazing has allowed the surviving trees to thrive. With the creation of the refuge, the warbler’s population grew from 3,526 to 11,920 in less than two decades, and vireo’s population on the refuge increased from 153 males in 1987 to 11,392 in 2013. 5 of 10 Sauta Cave National Wildlife Refuge (Alabama) This 264-acre refuge in the forest of northeastern Alabama was created to protect the endangered Indiana bat and gray bat. Gray bat populations plummeted due to mining, cave disturbance, vandalism, persecution, flooding, deforestation, and possible pesticides in the century leading up to their 1977 endangered listing. Thanks to the Sauta Cave National Wildlife Refuge, though, they have rebounded from a population of 2.2 million to 3.4 million in 2006. Meanwhile, the refuge has also provided a home for 250 federally endangered Price’s potato-bean plants, the imperiled Tennessee cave salamander, and the Rafinesque’s big-eared bat, among other species. 6 of 10 Penobscot River (Maine) Justin Lewis / Getty Images Dams built on the Penobscot, Maine's longest river, during the 19th century created a barrier for fish migrating to the ocean. Since, three of the 11 fish species that inhabit the river—the Atlantic salmon, the shortnose sturgeon, and the Atlantic sturgeon—have gained protection under the Endangered Species Act, which has led to two of the major dams being removed. Now, the fish can swim freely again in the only U.S. river that has a sizeable Atlantic salmon run. Healthy and thriving fish populations have enriched the river ecosystem by providing an abundance of food for birds and mammals. 7 of 10 Longleaf Pine Ecosystem (Southeast) Ryan McGurl / Getty Images Longleaf pine forests once covered around 90 million acres in the southeastern U.S. It was one of the most extensive forest ecosystems in North America before being targeted for logging and converted for agricultural and residential use. Longleaf pine is one of the country's most ecologically important trees, providing shelter for some 100 bird, 36 mammal, and 170 reptile and amphibian species, yet only 3.4 million acres remain of it today. The red cockaded woodpecker and gopher tortoise are two of the 29 longleaf pine-dependent species that have received protection under the Endangered Species Act, therefore saving these majestic beauties throughout the American Southeast. 8 of 10 National Key Deer Refuge (Florida) Wilsilver77 / Getty Images Established in 1957 to protect its namesake species, the National Key Deer Refuge covers 9,200 acres of the Florida Keys. The hoofed mammal that roams here is only 24 to 32 inches tall—a "toy" deer—and has fallen victim to hunting, poaching, and habitat destruction over the years. At the time of their Endangered Species Act listing in 1973, there were only a few dozen left, the Center for Biological Diversity report says, but the establishment of the refuge boosted the population to 800 by 2011. The refuge is composed of several diverse ecosystems, from freshwater wetlands to mangrove forests, all of which house more than a dozen endangered or threatened species. Birds and reptiles thrive in the deer haven as well. 9 of 10 Green Cay National Wildlife Refuge (Virgin Islands) Bill Ross / Getty Images Occupying a tiny 14-acre plot of land in the Caribbean, Green Cay National Wildlife Refuge was designated as a wildlife refuge in 1977, when its resident lizard, the St. Croix ground lizard, received endangered status. The island now plays home to the largest of the world's only two remaining natural populations of the lizard. Its numbers tripled—from 275 to 818—from the island's designation as a wildlife refuge to 2008. And as a bonus, the Caribbean brown pelican has also benefited. 10 of 10 Lake Erie (Great Lakes Region) Yuri Kriventsoff / Getty Images Even though the Lake Erie water snake that once populated the Great Lake's small islands isn't venomous—and actually helps bottom-dwelling fish and game species by gobbling up the predatory goby fish—it suffered mass killing and habitat loss prior to its 1999 endangered listing. After the snake received protection, more than 300 acres of inland habitat and 11 miles of shoreline from Lake Erie’s 34 islands were protected and restored to help save them. As a result, the Lake Erie water snake population increased from 5,130 (2001) to 9,800 (2010).