Some look like gargoyles, some have elaborate leaf-like noses and some are vampires, but all bats seem to fly into our world during the Halloween season. Northern Arizona University wildlife biologists are thinking about bats in October, too. But for the researchers the focus is on netting these creatures of the night to study their interaction with animals like skunks that may be susceptible to rabies and may come into contact with people and pets.
One particular pale-faced bat with white-tipped wings fluttered into the spotlight before we started buying Halloween candy and dusting off witch hats. The Phylloderma stenops now is making its way into research books as a bat species that exists in Nicaragua’s mature Mesoamerican tropical dry forest, one of the most endangered forest ecosystems in the world. This bat had never been documented in Nicaragua until Northern Arizona University’s batwoman arrived this year.
After two months of cutting through the vines and shrubs of this Central American country’s low mountains, side-stepping jungle-sized wasp nests and watching out for poisonous snakes, Dr. Carol Chambers’ heavily chewed, bat-handling gloves had been shredded, but not her hopes. This wildlife ecologist from NAU’s School of Forestry had expected to document a wide variety of bats, perhaps all 99 different species that existed in Nicaragua, despite the fact that their forest habitat was disappearing.
Chambers and other international bat conservationists became interested in the health of bat populations in the 12-mile wide isthmus between Lake Nicaragua and the Pacific Ocean after NAU research there revealed spider monkeys were being negatively affected by the increasingly fragmented forest. With pockets of mature forest shrinking and gaps between forest patches widening, spider monkey populations were becoming isolated and, as a result, inbred. The researchers wondered if bat populations were struggling as well.
“We were especially interested in a group of carnivorous bats in the leaf-nosed family because they prefer mature forest habitat. These forest-dwellers are not usually found in highly disturbed areas, so their presence can indicate whether forest restoration efforts could benefit the bat community.”
For centuries people have inhabited the hilly terrain, but the forest is rapidly being replaced by croplands of beans or rice that local farmers harvest or non-native forest plantations such as teak. The remaining forest, an important passageway for wildlife migrating between North and South America, is becoming more and more fragmented.
But bats are not a favorite animal in Nicaragua. Farmers consider them to be bloodsuckers that kill or sicken their livestock. So the ecological benefits that bats provide – eating harmful insects and pollenating forest plants – often go unappreciated.Chambers and a team of researchers from the United States and Canada teamed up with Bat Conservation International and Paso Pacífico to change attitudes about bats while catching, documenting and releasing the nocturnal creatures last winter. They stretched nets above streams and rivers. They also placed Anabats, echolocation-recording devises, throughout the forest to record sounds from different bat species.
In 35 nights of netting they caught nearly 1,500 bats representing 44 species. Weary from night hikes through thick vegetation and sore from untangling angry biting fruit bats whose teeth could eat through coconut shells, a bleary-eyed Chambers wondered if the white on the bat’s wings she was handling indicated scars. As she spread the wings for a closer look, Nicaragua’s foremost bat expert, Arnulfo Ramón Medina Fitoria, got goose bumps.
“Although he spoke only Spanish and I only English, I was beginning to understand that the large bat in my hands, with her short brown fur and long gray wings, was in fact our most incredible capture! In our second-to-last night in the forest, we caught a pale-faced bat, Phylloderma stenops, a new record for the country and a species that Arnulfo had wanted to capture for 11 years!”
Elated by the rare bat find, Chambers hopes to learn from the Anabat acoustic data whether this female is a nomadic loner or part of a larger community roosting in the tropical forest. “Our work already has paid off. We have added to our knowledge of bats in Nicaragua and documented a larger range for four species. We’ve also helped local people understand the value of bats and importance of conserving dry tropical forests.”
While more bats were captured in areas that had been logged and farmed, more species were caught close to large patches of mature forest. “The existing patches are helping forest bats maintain a foothold in this region but they need to be larger and more connected on the Paso del Istmo,” said Chambers.
Paso Pacífico, an organization dedicated to restoring and conserving natural ecosystems of Central America’s Pacific slope,will continue to monitor Nicaragua’s bat populations and threats to their survival. Meantime, Chambers is counting on a return visit and perhaps identifying 101 reasons to conserve mature forests and celebrate bats beyond Halloween!