Abandoned Israeli army bunkers along the Jordan River are providing a lifeline for bats on the endangered species list, researchers say.
Soldiers left Israel's underground forts along the frontier with Jordan after a 1994 peace treaty between the two countries. With much of the former front line, some of it dotted by mine fields, still designated by the military as off-limits to civilians, bats swooped into the secluded and dark steel caverns.
Several years ago, researchers from Tel Aviv University were granted access to the ghost bunkers. Now, they say, they have identified 12 indigenous bat species in the 60-mile-long tract between the Sea of Galilee in Israel and the Dead Sea's northern edge in the occupied West Bank.
Two of the species commonly known as the Mediterranean horseshoe bat and Geoffroy's bat are on the critical list and three others are designated as endangered.
"There is no doubt that by being in a closed military zone that has prevented human interference, the bat habitat will allow these delicate creatures to thrive," said one of the researchers, Eran Levin.
But he said it was too early to quantify the growth of the local bat population, estimated to be in the thousands, because the research project was not yet complete.
One former bunker -- overlooking the spot along the Jordan River where some Christian faithful believe Jesus was baptized by John -- has been turned into a more accommodating home for the webbed-wing mammals.
To give the bats more grip, the research team roughed up its smooth steel and concrete walls, suspended mesh sheets and wooden palates, sprayed insulating foam and stuck stones to surfaces.
Different bat species each preferred different grip surfaces, Levin said.
A thick layer of bat guano now covers the floor and metal bunk-bed frames the military left behind.
A night-vision camera follows the bats' movements during the period they inhabit the bunkers from March to October when daytime temperatures in the area soar above 40 degrees Celsius (104 Fahrenheit).
Enjoying their own peace dividend, the bat population could also give something back to Israelis, Jordanians and Palestinians in the area.
Aviam Atar of Israel's Nature and Parks Authority said the bats help to reduce crop damage by eating insects at night, coming out to feed in the dark when the fields are empty.
"Because each bat can eat a few grams of insects each night, they reduce the need for the use of pesticides and this certainly has potential for facilitating green farming. The crop growers don't even know this is happening," he said.