U.S. Fish and Wildlife Service declares 23 species extinct

MISSOULA — We learned Wednesday that the U.S. Fish and Wildlife Service has declared 23 species of birds, fish, and other species extinct.

Probably the most famous species on the list is the Ivory-Billed Woodpecker, which some thought had been seen in the swamps of the southern U.S. in recent decades.

The U.S. government is declaring the splendid ivory-billed woodpecker -- and 22 more birds, fish and other species-- extinct.

It's a rare move for wildlife officials to give up hope on a plant or animal, but government scientists say they've exhausted efforts to find these 23.

And they warn climate change, on top of other pressures, could make such disappearances more common as a warming planet adds to the dangers facing imperiled plants and wildlife.

The factors behind the disappearances vary - too much development, water pollution, logging, competition from invasive species, birds killed for feathers and animals captured by private collectors. In each case, humans were the ultimate cause.

Another thing they share: All 23 were thought to have at least a slim chance of survival when added to the endangered species list beginning in the 1960s.

Only 11 species previously have been removed due to extinction in the almost half-century since the Endangered Species Act was signed into law.

Wednesday's announcement kicks off a three-month comment period before the species status changes become final.

Around the globe, some 902 species have been documented as extinct. The actual number is thought to be much higher because some are never formally identified, and many scientists warn the earth is in an "extinction crisis" with flora and fauna now disappearing at 1,000 times the historical rate.

It's possible one or more of the 23 species included in Wednesday's announcement could reappear, several scientists said.

A leading figure in the hunt for the ivory-billed woodpecker said it was premature to call off the effort, after millions of dollars spent on searches and habitat preservation efforts.

What's lost when those efforts fail are creatures often uniquely adapted to their environments. Freshwater mussel species like the ones the government says have gone extinct reproduce by attracting fish with a lure-like appendage, then sending out a cloud of larvae that attach to gills of fish until they've grown enough to drop off and live on their own.

The agency provided details of the following species:

• Ivory-billed woodpecker – Once America’s largest woodpecker, it was listed in 1967 as endangered under the precursor to the ESA, the Endangered Species Preservation Act (ESPA). The last commonly agreed upon sighting of the ivory-billed woodpecker was in April 1944 on the Singer Tract in the Tensas River region of northeast Louisiana. Despite decades of extensive survey efforts throughout the southeastern U.S. and Cuba, it has not been relocated. Primary threats leading to its extinction were the loss of mature forest habitat and collection.
• Bachman’s warbler – As early as 1953, Bachman’s warbler was one of the rarest songbirds in North America. When first listed in 1967 as an endangered species under the Endangered Species Preservation Act, the bird had not been seen in the U.S. since 1962. Last documented in Cuba in 1981, there have been no verifiable sightings in that country since then. The loss of mature forest habitat and widespread collection are the primary reasons for its extinction.
• Eight species of freshwater mussels – Reliant on healthy streams and rivers with clean, reliable water, freshwater mussels are some of the most imperiled species in the U.S., home to more than half of the world’s species of freshwater mussels. Mussels proposed for delisting due to extinction are all located in the Southeast, America’s biodiversity hot spot for freshwater mussels. They are the: flat pigtoe (Mississippi), southern acornshell (Alabama, Georgia, Tennessee), stirrupshell (Alabama), upland combshell, (Georgia, Alabama, Tennessee), green-blossom pearly (Tennessee, Virginia), turgid-blossom pearly mussel (Tennessee, Alabama, Arkansas), yellow-blossom pearly mussel (Tennessee, Alabama) and the tubercled-blossom pearly mussel(Alabama, Illinois, Indiana, Kentucky, Tennessee, West Virginia, southern Ontario, Canada).
• Hawaiʻi and the Pacific Islands – Eleven species from Hawaiʻi and Guam are being proposed for delisting due to extinction, many of which had striking characteristics, such as the long curved beaks of the Kauai akialoa and nukupuʻu, the haunting call of the Kauai `o`o, and the brilliant colors of the Maui akepa and Molokai creeper. Species endemic to islands face a heightened risk of extinction due to their isolation and small geographic ranges. Hawaiʻi and the Pacific Islands are home to more than 650 species of plants and animals listed under the ESA. This is more than any other state, and most of these species are found nowhere else in the world.
• San Marcos gambusia – Listed in 1980, this freshwater fish was found in the slow-flowing section of the San Marcos River in Texas. The San Marcos gambusia had a limited historic range of occurrence and has not been found in the wild since 1983. Primary reasons for its extinction include habitat alteration due to groundwater depletion, reduced spring flows, bottom plowing and reduced aquatic vegetation, as well as hybridization with other species of gambusia.
• Scioto madtom – Listed as endangered in 1975, the Scioto madtom was a fish species found in a small section of the Big Darby Creek, a tributary of the Scioto River, in Ohio. The Scioto madtom was known to hide during the daylight hours under rocks or in vegetation and emerge after dark to forage along the bottom of the stream. Only 18 individuals of the madtom were ever collected with the last confirmed sighting in 1957. The exact cause of the Scioto madtom’s decline is unknown, but was likely due to modification of its habitat from siltation, industrial discharge into waterways and agricultural runoff.

“The Endangered Species Act has been incredibly effective at preventing species from going extinct and has also inspired action to conserve at-risk species and their habitat before they need to be listed as endangered or threatened,” said Deb Haaland, the Secretary of the Interior. "We will continue to ensure that states, Tribes, private landowners, and federal agencies have the tools they need to conserve America’s biodiversity and natural heritage.”