Malayan Slit-Faced Bat (Nycteris tragata)
This species is named after the deep slit running down the face, from a central point between the eyes down to the nostrils. This is, in fact, part of the nose leaf, which the hollow-faced bat needs for echolocation. Folds of skin extend from either side of the slit to direct echolocation calls with great accuracy, leaving little space for the minute eyes. The ears are brown and particularly long, with a short, rounded tragus (inner ear). The tail is commonly equal in length to the head and body, and is enclosed in a membrane that stretches between the hind legs (the interfemoral membrane). A tiny triangular cut in the membrane where the tail reaches the edge helps to identify the species. The hollow-faced bat is very furry, with a greyish-brown back, paler underside, and even brown fur on the forearms. The wings are very broad and short, with a large area of membrane above the forearm (known as the propatagium). This gives the bat great agility, but reduces its flight speed.
This species' distribution includes Myanmar,
Peninsular Malaysia, Sumatra (Indonesia) and throughout Borneo (Simmons
2005).The type locality for this species is Bidi caves, Sarawak, Borneo
Brunei Darussalam; Indonesia; Malaysia; Myanmar; Singapore; Thailand
This species is uncommon.
Population Trend: Decreasing
Biology and Ecology
Although this insect-eating species is capable of complex echolocation calls involving a rapid, low intensity sweep of the frequency range, it is also thought to hunt simply by listening for sounds made by the insects themselves. Its large wing area and comparatively low body weight allows it to take off nearly vertically from the forest floor when hunting, possibly with heavy prey . It tends to hover over its prey before snatching it up into the air . There are thought to be two breeding seasons per year, with females giving birth to a single pup. At first the pup is carried in foraging flights, which may well limit the diet of the hollow-faced bat, as it can only take lighter prey. The pup learns quickly to fly and forage alone, and at one year old will be sexually mature .It has been collected from primary Dipterocarp forest and peat swamp forest (I. Maryanto pers. comm.). It roosts in small groups in fallen tree hollows and similar man-made hollows such as culverts as well as crevices of large boulders and in limestone caves.
The major threat for this species is habitat loss due to
deforestation for logging, plantations, agriculture, as well forest fire.
The species range includes several protected areas