Kitti's Hog-Nosed Bat: Craseonycteridae

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KITTI'S HOG-NOSED BAT: Craseonycteridae

PHYSICAL CHARACTERISTICS

The only species in the Craseonycteridae family is Kitti's hog-nosed bat or simply, hog-nosed bat. They are also called bumblebee bats, because they are about the size of a bumblebee. This species was unidentified until 1974.

Kitti's hog-nosed bat is considered the word's smallest mammal. The head and body combined measure only 1.1 to 1.3 inches (29 to 34 millimeters), and they weigh about 0.7 to 0.9 ounces (2.0 to 2.6 grams), which is about the weight of a dime. These bats have a wingspan of about 6 inches (15 centimeters), which is smaller than some butterflies.

The name hog-nosed refers to the bat's facial appearance. Their muzzle is pig-like, with two wide, crescent-shaped nostrils. Their ears are relatively large with rounded tips. They extend beyond the snout when the bat is lying forward. Their eyes are relatively small and partially hidden by fur. Hog-nosed bats have long and broad wings with pointed tips. Fur on the back may be a brown to reddish brown and its belly is typically paler. These bats have twenty-eight teeth.

Kitti's hog-nosed bats have long, slender feet and a short thumb with a well-developed claw. They do not have an external tail. Males have a glandular swelling at the base of the throat. The bumblebee bat also has a web of skin between its hind legs, which is thought to help with flying and catching insects.

GEOGRAPHIC RANGE

Kitti's hog-nosed bats were once found only in Thailand. Most of these bat populations were located in Sai Yok National Park. In 2001 a second population of bumblebee bats was found in a cave in Myanmar.

HABITAT

Bumblebee bats have been found deep inside small, remote limestone caves, caves formed by water dissolving calcium carbonate rock. Hog-nosed bats appear to prefer caves with multiple chambers and domed roofs located near rivers or areas with water.

DIET

Kitti's hog-nosed bats feed on insects, including spiders, beetles, small flies, wasps, and bark lice. They hunt their prey (animals they eat) through echolocation (eck-oh-loh-KAY-shun), a technique in which the bats emit high-pitched sounds that bounce off objects. The bats then detect the objects around them by listening to the sounds' echoes. These sounds are too high pitched for humans to hear.

BEHAVIOR AND REPRODUCTION

Hog-nosed bats are crepuscular (kri-PUS-kyuh-lur), meaning that they are active at dawn and dusk. These bats are most active in the evening. A few minutes after the sun sets they leave the cave and fly in a circular pattern above the cave entrance for about one minute before flying away. They then separate into small groups and head off to a foraging area, a place to search for food, which is usually relatively close, within 820 feet (250 meters) of the cave.

Hog-nosed bats eat for about thirty minutes then return to the cave for the night. They are active again during the hours before sunrise. In the early morning they feed and then return to the cave.

The bats roost (settle or rest) together in caves in small numbers of up to fifteen individuals. While they roost together, the bats appear to be independent. They roost alone instead of clustered together with others.

From the shape of their wings and stomach content it appears that they can hover to catch their prey. It is unclear exactly how the hog-nosed bat captures its food. It could snatch small insects off surrounding leaves, twigs, or other surfaces. It could hunt near the ground. Other observations conclude that these bats may catch insects on their wings while flying.

Little is known about the hog-nosed bat's mating habits. The species is thought to be polygamous (puh-LIH-guh-mus), meaning that they have more than one mate during the mating season. There is evidence to show that the bats have their young during the beginning of the summer's rainy season.

KITTI'S HOG-NOSED BATS AND PEOPLE

People have caused the population of hog nosed bats to decline by disturbing their habitats and food supplies. Much of the areas around the bats' caves have been cleared for agriculture. Recreation and tourism are also reasons for the disruption of the bat's habitat and the resulting decline in population.

CONSERVATION STATUS

Kitti's hog-nosed bats are listed as Endangered, facing a very high risk of extinction, dying out, by the IUCN; they are one of the rarest bats in the world.

HOLY BAT DISCOVERY!

The discovery of the tiny bumblebee bats set a new record for the smallest bat in the world. The Kitti of Kitti's hog-nosed bats refers to Kitti Thonglongya, who collected the bat in Thailand in 1968. Thonglongya went on to collect and discover other new bat species, such as the extremely rare Salim Ali's fruit bat.