The causes Area’s endangered species harmed by disease, development
The giant panda moved off the endangered species list in the past month, but seven bee species took its place. Both moves grabbed headlines around the globe, but not all animals facing extinction can make that claim.
Benton and Washington counties are home to six creatures most people have never heard of that are listed as endangered, including three bats, a clam, a beetle and a crayfish.
The Arkansas Game and Fish Commission lists 18 species statewide being closely monitored to make sure they remain viable in the state. The national list is 1,442 species, according to the U.S. Fish and Wildlife Service. The federal agency is responsible for listing animals protected by the 1973 Endangered Species Act.
Northwest Arkansas’ endangered species may be obscure creatures that primarily inhabit caves, but their needs are as precious as those of humans, researchers say.
“They need a nice place to live, they need clean water and they need a way to make a living,” said Tim Snell, associate state director for The Nature Conservancy of Arkansas. “What is good for the animals, whether they are endangered or not, are those same things that are important for people.”
Even the smallest and most fragile of endangered creatures locally, such as the Benton County cave crayfish, are essential to a healthy environment, Snell said.
“The classic example is the canary in a coal mine. The coal miners would carry a small canary in a cage into the coal mine, so that if the canary started to have difficulty breathing, they would know the air is running out or the air is bad,” he said. “The same thing is true of the environment. A small organism can oftentimes give an indication that the health of the environment is deteriorating, and the health of the environment is very important to humans.”
The area’s endangered species are threatened by human contamination, including industrial pollution and an incurable bat disease.
Agencies such as The Nature Conservancy and Fish and Wildlife work to protect endangered species, including purchasing caves where such species live and using metal bars and fencing to protect those caves.
Three threatened species also call the two-county area home. The U.S. Fish and Wildlife Service states threatened species are “likely to be at the brink in the near future.”
The animals
The six endangered animals in Northwest Arkansas are evenly split between invertebrates, or animals lacking a backbone, and vertebrates.
All three endangered vertebrates are bats — the Ozark big-eared bat, gray bat and Indiana bat. All three live in Washington County. Benton County has the gray bat and Indiana bat, but not the bigeared bat.
The three species of bats have been endangered since the 1970s, said Blake Sasse, bat biologist for the Game and Fish Commission.
“Those are mainly endangered due to human disturbance to the caves where they are hibernating or raising their young,” he said.
Endangered invertebrates in Benton and Washington counties include the cave crayfish, Neosho mucket and the American burying beetle.
Cave-dwelling invertebrates can be unique to that cave system, said Bill Holimon, chief of research at the Arkansas National Heritage Commission.
“If you have a population of something that is isolated from other members of its species, over time for various reasons it can become very adapted or have genetic drift related to isolation,” he said.
The Ozark cave fish is a threatened vertebrate that inhabits caves in Arkansas, Oklahoma and Missouri.
The highest number of those cave fish exist in Cave Springs’ cave, said Mike Slay, Ozark Karst Program director for The Nature Conservancy of Arkansas. Slay is regarded by peers as one of the foremost experts on cave fish.
Cave fish evolved over time to live in dark conditions, losing both their pigment and eyes, Slay said.
“Pigment is useful for protecting yourself from getting a sunburn, (but) it’s dark under there, so they don’t need that,” Slay said. “And they lose their eyes because they don’t need them; you’re not going to be able to use eyesight in 100 percent darkness.”
Endangered and threatened fresh water mussels the Neosho mucket and rabbitsfoot inhabit rivers, not caves. Bill Posey, assistant chief of fisheries for Game and Fish, has found both types of mussels in the Illinois River.
The mucket population is scattered across Arkansas, Oklahoma, Missouri and Kansas. The population separation is to the mucket’s detriment, Posey said.
“Those populations have been separated because of dams,” he said. “There’s no more genetic flow between the populations. You end up with a kind of bottleneck because you’re not getting new genes in. The more genetic material, the more genetic diversity you have, the more resiliency you have for diseases and catastrophic events.”
A disease called whitenose syndrome is a fungus threatening some bat species. The fungus causes irritation to the bat’s skin and nose, causing him to wake up during hibernation in winter and fly, said Allison Fowler, a biologist for the Arkansas Game and Fish Commission. The disease showed up in the state a few years back and has spread through several counties.
White-nose syndrome has made the northern long-eared bat nearly endangered, Fowler said.
“It’s a disease that we can’t really do anything about,” she said.
Sasse said the disease originated in Europe or Asia and was discovered in the United States in 2006.
“Millions of bats have died because of this,” he said. “In some caves, you might lose 99 percent of the bats.”
Matt Covington started caving when he was a child. He teaches geology at the University of Arkansas and said it’s possible white-nose spores were brought to the United States by bats that latched onto shipping containers. He acknowledged it’s also possible cavers unknowingly brought the white-nose spores into the United States.
“There’s a lesson to be learned about what we can do by accidentally moving caving gear from one place to another. It could have happened that way. Clearly it’s something we can learn from and be careful about,” Covington said.
Cave fish took a different route to make the threatened list, becoming a novelty to researchers in the 1950s.
“There were museums and researchers that were really interested in studying these particular species,” Slay said. “They would come to our caves where this species occurs and collect a whole bunch of them.”
Darkness in caves causes food to be scarce. Because there is little food available for cave fish, they do not reproduce often, and when they do, the number of babies is low, he said.
Cave fish being listed on the endangered species act protected them from being collected, Slay said. However, incompatible land use changes, including suburban and industrial development, also have threatened cave fish by making the groundwater entering the cave less pure, he said.
“When there’s development going on, you have all that earth work that’s going on, you have the risk of sediment being picked up by rain and flushed into the cave system,” he said.
The number of cave fish in the Cave Springs Cave rebounded from as low as 50 in the 1950s and 1960s to around 150, which is the largest cave fish population and nearly double the combined number of cave fish in the other sites the species is known to exist in, Slay said.
“It makes it really important to ensure the population at the Cave Springs cave is protected,” he said.
Limited habitat is a primary reason the cave crayfish is endangered, said Brian Wagner, nongame aquatics biologist for the Game and Fish Commission.
“It’s reliant on cave and groundwater habitat, and it’s just found in a few caves in Northwest Arkansas,” Wagner said.
Mucket and rabbitsfoot populations are harmed by contamination as well, according to the Fish and Wildlife Service website.
The American burying beetle has become endangered because of land development, Davidson said.
The solutions
Cavers need to follow procedures developed by the U.S. Fish and Wildlife Service for decontaminating caving equipment, which has evolved with growing knowledge, Covington said.
“The main method is cleaning the gear and then submerging the gear in 50 degree Celsius hot water for 20 minutes to decontaminate it,” he said. Gear that can not be submerged in water, such as cameras, should be wiped down with bleach or Lysol.
The best way to protect bats is to avoid visiting caves with heavy bat populations to avoid
spreading the fungus and disturbing the bats, especially during winter time when they hibernate, Covington said.
Robert Ginsburg has been exploring caves for 25 years. He said access to caves on public lands has been cut off since white-nose syndrome has become such an epidemic, but if permission can be gained, exploring privately owned caves is fair game.
“You still have to be conscious of the potential to do damage,” he said. “Your awareness needs to be heightened because your presence is going to impinge on the ecosystem of a cave, and it’s a very fragile ecosystem.”
Ginsburg said anyone who visits a cave should visit the National Speleological Society’s website caves.org and learn how to visit caves responsibly.
Scientists are working to counteract white-nose syndrome although there is no cure, Sasse said.
“There are treatments being tested to control the fungus, but it’s still in its early stages,” he said.
Land management agencies such as the National Park Service and U.S. Forest Service try to protect bats by covering cave entrances with fences or closing them with horizontal bars that still allow bats to fly though. Some caves in Northwest Arkansas have been protected with such methods, Sasse said.
There have also been efforts to ensure the best land conversion practices to maintain high-quality water and protect the cave fish, Slay said.
“We worked with a couple of different consulting firms and developed a manual of best management practices to be used to ensure that ground water is protected for the cave fish population at Cave Springs,” Slay said. “It resulted in the development of a document that has all these requirements
in it.”
The document, which is referred to as the Cave Springs Best Management Practices, requires developers to comply with practices that protect water resources that affect cave fish, Snell said.
“It’s a lot of practical stuff. It’s not anything that will stop development. It’s how to develop wisely,” he said.
Tom Hopper, who works for Crafton Tull, a firm made up of architects, engineers and surveyors, said Lowell and Rogers adopted the practices into their ordinances and that Cave Springs and Springdale are both considering adopting the practices.
Rainwater from Cave Springs, Rogers, Lowell and Springdale pours into a recharge area, which provides water to Cave Springs cave, thus recharging the cave’s stream, Hopper said.
A fence is kept around the Cave Springs cave to prevent people, who have been known to trample cave fish, from directly harming cave fish, Slay said.
Agencies protect crayfish by purchasing caves that are known habitats, such as Logan Cave National Wildlife Refuge in Siloam Springs, purchased by Fish and Wildlife, and Bear Hollow Cave in Bella Vista, purchased by the Nature Conservancy, Wagner said.
Logan Cave became the 455th National Wildlife Refuge on March 14, 1989, under the Endangered Species Act of 1973, according to the Fish and Wildlife website. The Nature Conservancy would like to do more, Snell said.
“Most of them are competitive grant programs, and it’s based on the recovery of endangered species,” he said. “If funding became available we would help to protect the caves, but we don’t have any funding (for that) right now.”