MANHATTAN — As dusk arrives and temperatures start to fall, out come Central Park's hordes of insects. Right behind them are the winged predators that keep them in check — bats.
The Urban Park Rangers will shine a spotlight on these flying mammals — less a threat to New Yorkers than the city's pesky bugs — when they lead an hour and half bat tour on Aug. 20, starting at 7:30 p.m. at Belvedere Castle, a favorite spot for the little creatures.
Because they are so fast and tiny, many park-goers don't even notice bats, said Richard Simon, deputy director of the Urban Park Rangers.
"There are probably hundreds of them in the park. We've never done a count," Simon said. "They're very hard to see because they're so quick. And they're so small. The little brown bats are two inches. They have a four-inch wing span."
New York State has nine bat species — none of which live up to the blood-sucking stereotype.
The six cave dwelling varieties are not common in the city, but the others crawl up the bark of trees and on the eaves of buildings, Simon said.
Because the little critters are so "beneficial" in keeping bug populations down, the Parks Department often sets up wooden bat houses — that scores of the teeny fliers huddle into — throughout the city's green spaces, Simon said. He didn't know how many such houses were in Central Park.
"Most large parks in the city have a few of them," Simon said.
"You don't really see [bats], but you definitely feel their impact. They keep insect and mosquito populations down," he said. "They're one of the most beneficial creatures we have in the city.
"The hawks are great in terms of eating rodents. But they probably eat one or two rodents a day, while bats are eating hundreds of mosquitoes a day."
Certain bat species can eat 1,000 mosquitoes in just one hour, according to scientists.
The tour will likely move from Belvedere Castle to Turtle Pond, another feasting ground for the bats.
The Urban Park Rangers will try to clear up myths about the little animals, which have wings that are very different to birds' wings. They have digits similar to human fingers with a thin membrane over them to create their wings, Simon explained.
"I think people who don't know much about bats tend to be afraid of them," Simon said. "Some people worry they might fly into their hair or they're vampires. But in New York City they're very important to the ecosytem."
Bat populations across the country have seen an alarming decline because of something called White-Nose Syndrome. The epidemic is causing alarm on Capitol Hill where it was the subject of an oversight hearing in June.
Since it was first discovered in 2006 in Albany, White-Nose has killed more than 1 million bats in 18 states, according to testimony given by U.S. Rep John Fleming, of Louisiana, who chairs the House of Representatives subcommittee on fisheries, wildlife, oceans and insular affairs.
"Bats consume vast amounts of insects," said Fleming, citing a "Science" magazine article that estimated their value to U.S. agriculture at $3.7 billion to $53 billion a year.
Six federal agencies and various states have spent more than $16 million on the problem, however they were "apparently no closer to stopping this disease which has devastated more than half of the 47 species of bats native to North America," he said.
New York City hasn't seen a decline in the bat population, Simon claimed.
"If anything, there may be a small increase," he said. "The habitat has gotten better and become friendlier to many animals. There's more biodiversity, more things in the food chain for everyone."
Bats are a "vector" species, so they are capable of carrying rabies and spreading rabies to other animals, Simon said. But there's been no known bat to human rabies transmission, he added.
Simon hopes the Urban Park Rangers event will give New Yorkers a new appreciation for the bats that flutter around in the shadows of the night.
"We're trying to open New Yorkers' eyes to what's around them every day," he said.