Alabama has long celebrated the remarkable biodiversity within its borders, but having a huge number of species means the state also has a large number of species at risk of extinction.

According to the U.S. Fish and Wildlife Service, Alabama has 151 endangered or threatened species, the third most of any state. Only Hawaii (484 species) and California (286) have more.

Alabama’s species include slimy salamanders like the Black Warrior waterdog, massive mammals like the West Indian manatee, and majestic birds like the whooping crane and red-cockaded woodpecker.

Biologist and author Scot Duncan, who taught at Birmingham-Southern College for 20 years and is the author of the book “Southern Wonder: Alabama’s Surprising Biodiversity,” said the state’s large number of freshwater rivers and creeks contribute to its high number of unique species.

“Alabama has a very high concentration of freshwater species,” Duncan said. “We’re the number one state for freshwater fishes, freshwater mussels and snails, crayfish, freshwater turtles, some other taxa as well.

“And many of those species are only found in Alabama, or found mostly in Alabama, and a little bit in an adjacent state. And so being as how we have so many species here, that sort of sets the context for why we’ve got so many endangered species.”

Alabama’s 151 threatened or endangered species includes:

• 71 freshwater mussels, 13 snails, and two crustaceans, including the Alabama cave shrimp.
• 21 flowering plants and three ferns – in total Alabama has 28 species of plants that are found nowhere else in the world, though not all of them have made the endangered list.
• 16 fish species, including the elusive Alabama sturgeon, several species of darters, and the Alabama cave fish.
• 10 reptiles and three amphibians, including the eastern indigo snake, the Red Hills salamander, and the Alabama red-bellied turtle.
• Six mammals, including three species of bats and two species of beach mouse that play a vital role in the state’s coastal dune ecosystem.
• Five birds and one insect, the Mitchell’s satyr butterfly.

Duncan said Alabama also has the second highest number of extinctions in the modern era, primarily because of the number of large hydroelectric dams built along the state’s rivers that flooded out sensitive ecosystems.

“Dams change the ecology of these ecosystems in some fundamental ways that are seriously damaging to native species and native ecosystems,” Duncan said. “Dams change the depth of the water, the temperature, the water, the flow of nutrients, the flow of sediments, the availability of oxygen in the water for animals, interrupts the migration of fishes and other species that migrate up and down the rivers as part of the natural life cycle in order to reproduce.

“So the combination of having lots of freshwater species in Alabama, plus the fact that we’ve dammed so much of our rivers and creeks, that’s the reason why we’re in the number three position for threatened or endangered species.”

Duncan said that Alabama also has seen the second most extinctions of any state in modern times.

“We are in the number two position for extinct species across U.S. states and territories,” Duncan said. “The only state ahead of us is Hawaii.

“But if you look just at U.S. states that are on the continent, Alabama is the number one state for extinction. And again, it comes back to those two same factors: we’ve got so many freshwater species in the state and our history of how we have we’ve managed our rivers and creeks. And that has led to the extinction of many, many species in the state, primarily, freshwater snails and mussels, and a couple of fish species as well.”

Duncan, who left Birmingham-Southern last year to become executive director of Alabama Audubon, said he is working on another book called “Southern Rivers: Saving America’s Freshwater Biodiversity” to explore ways to protect Alabama’s numerous endangered species, and why saving those species will also be beneficial to the people living in those areas.

“The same things causing problems for freshwater species in the Southeast are causing water availability problems for us here as well, water availability and water quality problems,” Duncan said. “And as it turns so as it turns out, we humans are suffering the same difficult future in terms of freshwater in the Southeast, as are all these endangered species.

“The best solutions for protecting species and protecting our water supply, they’re the same solutions. And so the future that we need to have is all about doing the right thing for us and the right thing for biodiversity. And that’s the future that we need to be working towards.”

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