In Australia, a bat call widens the known map
· BehindLines newsroom
In northern Australia, a sound recording has widened the known map of an elusive bat. A communication from Australian Wildlife Conservancy, picked up on 30 October by EcoVoice, describes the identification of the Arnhem sheath-tailed bat at Pungalina-Seven Emu. The site lies about 650 kilometres east of the species' previous most easterly detection, near Jabiru.
Ecologist Oli Aylen was setting up nets near mangroves when a device recorded an unusual signal. He then passed it to Damian Milne, a bat specialist with the Northern Territory government, who confirmed the identification, according to this account. The information concerns a call that was detected; it does not describe the capture of this animal.
Taphozous kapalgensis remains little known. The Australian Museum's fact sheet notes that the species was only discovered in 1979. It eats insects in flight and hunts notably over the treetops of swamps and open forests. The museum keeps a conditional tone about its resting places: tree hollows or the base of pandanus leaves are possibilities, not roosts now located by this detection.
Listening complements trapping. In a review published in September, AWC explains that surveys at Pungalina-Seven Emu combined live trapping with ultrasonic recorders. They recorded eighteen species of small bats, six of them new to the sanctuary's list. A new entry in this inventory is not a species newly discovered by science.
It is also necessary to distinguish an extension of knowledge from an observed movement. The distance between two detections does not prove a journey of 650 kilometres. It shows that a presence had until now been poorly documented. Further research will need to clarify the distribution and the roosts, without turning this single signal into an estimate of the population.