ST. GEORGE- In a cave system shaped by tectonic forces cracking ancient limestone, conditions are ideal for hosting one of southern Utah’s largest known bat colonies.
But just because biologists know there are plenty of bats in Bloomington Cave from year to year doesn’t mean it’s easy to catch and catalog them during annual surveys.
One such examination was recently conducted on April 25 by a team from the Utah Division of Wildlife Resources. This year, as in previous years, the primary focus was tracking down one of the deadliest threats to bats in the United States: White Nose Syndrome.
“We have quite a few bat species here where it’s not at all understood how they’re going to react to white nose (syndrome), if they do,” said Keith Day, native species biologist with state wildlife. agency. “We don’t know exactly what’s going to happen – I would really say ‘if’ – but probably when it will come out here.”
Caused by an invasive species of fungus (Pseudogymnoascus destructans) that thrives in the cold, damp conditions typical of caves, white nose syndrome is estimated to have killed millions bats since it was first detected in North America in 2006.
The disease has spread across the continent from east to west, carried by migrating bats and unwitting cavers carrying the fungus on boots, clothing and climbing gear. Utah is among the last western states without a confirmed case, along with Arizona, Nevada, Idaho and Oregon.
Catch crafty cave dwellers
While surveying Bloomington Cave, biologists sought to determine if local bat colonies remain uncontaminated, deploying several fine-mesh nets over the main cave entrances to catch bats. as they emerged in the hours just after sunset.
“Success is not positive samples,” Day said. “We may be getting bats from other areas, so if we get positive bats, it may mean bats are coming in and bringing them from somewhere else.”
After carefully disentangling the winged mammals from the nets and placing them in a soft cotton bag to weigh them, the biologists removed the bats’ wings and noses, recorded key body measurements and identified the sex and species. of each bat.
None of the seven bats captured during the evening survey showed signs of white nose syndrome, although Day said they planned to return for further testing to obtain a larger sample.
Earlier surveys carried out over the winter at Mammoth Cave and Bower’s Cave in Garfield County also showed no signs of the deadly fungus, meaning it’s likely the disease didn’t reach the bats. from Utah.
Surveys are conducted annually at Bloomington Cave, Mammoth, and Bower’s Cave due to the relatively large bat colonies they house. However, colonies like these are probably the exception and not the rule in southern Utah.
Even large western caves don’t support massive colonies like those often found in the eastern United States, Day said.
“A lot of our bats probably roost in ones, twos and fives in the cracks and crevices of the cliffs,” he said. “I know of a few colonies that may have a few hundred bats, but nothing like the numbers you see in the rest of the country.”
What Utah lacks in population, it makes up for in variety: Beehive State is home to at least 18 of the nation’s 47 bat species.
Several species of the genus myotis (meaning mouse ears) are commonly found in southern Utah, including thysanodes myotis, or fringed myotis. Day and his team caught fringed forget-me-nots and Townsend’s big-eared bats which apparently share use of Bloomington Cave’s mile and a half of caverns and corridors.
Why bother with those furry flyers?
Researchers are still struggling to piece together the big picture of bat health and their relationship to their local environment. The behavior, preferred habitat and size of bats make them difficult research topics, but some clear patterns emerged that Day and his colleagues would like more people to be aware of.
First, individual bats pose little danger to humans. Since all bats in Utah are insectivores, if ever a bat approaches a person traveling at night, it’s definitely not looking for blood.
“Bats aren’t afraid of humans at all,” Day said. “As far as I know, being around humans doesn’t bother them. They are curious animals, so they can fly up and watch you, then walk away.
Although much has been said about the risk of infection from interacting with a live or dead bat, the truth is that most bats do not carry rabies – although you should contact the Utah Division of Wildlife Resources to remove nuisance bats rather than dealing with them yourself.
Kyle Voyles, outdoor recreation manager and cave coordinator for the Bureau of Land Management, has certainly seen his fair share of animals while exploring caves around the world. Voyles joined the Bloomington Cave team for their evening survey and shared his insight into the role bats play in the animal community.
“Bats definitely play a very important role in the cave micro-ecosystem,” he said. “Many of the invertebrates that live in cave systems are detritivores, which means that they eat anything that falls on the ground. ) – this is what feeds many insects.
The nutrients bats bring into the cave environment support a microcosm unique to Bloomington Cave: Researchers identified six new species of invertebrates there in 2011. These newly described creatures were connected to bats. -mice via the larger cave food web.
Finally, when it comes to helping people, the most direct benefit of local bats is their voracious appetites. A single bat can eat hundreds of insects in one night, keeping mosquito, moth and beetle populations under control.
These benefits also translate to agriculture, where bats serve as a free and natural form of pest control. A economic analysis of the value brought by bats to North American Agriculture have estimated that bats could contribute between approximately $4 billion and $53 billion in pesticide savings.
Thus, protecting the health of bats ensures that their contributions in the form of pest control and their role in the food web are preserved. Ongoing investigations provide more data to better understand how bats and humans interact and to eventually find a solution to threats like white nose syndrome.
“I just want the public to know that bats are friends, not foes,” Voyles said. “They’re not the flying rats people say they are. We share the same territory: people go to caves where bats live, but they will respect us if we respect them.
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