Serotine

A large bat. Forearm length 48-50mm. Tail length 30-55mm. Weight 21-31g. The whole body is covered with short hair, the back hair is brown, the tip is slightly luminous short white hair, the body is white yellow brown, the wing membrane is light yellow brown. The lower part of the body, the chest, and the abdomen are covered with gray brown hairs. The ears are short, thicker at the base, folded forward beyond the rostral end. The tragus is larger, with a wider base and a tapered end. The alar membrane is developed, ending at the base of the toe. The caudal membrane is triangular in shape and has white hairs on it. It is triangular from the edge of the membrane, the tail is developed, and it runs through the tail membrane, only the end is slightly prominent, about 2/3 of the body length.

In China, it is widely distributed in Heilongjiang, Jilin, Liaoning, Hebei, Inner Mongolia, Beijing, Shanghai, Tianjin, Henan, Shandong, Shanxi, Anhui, Jiangsu, Zhejiang, Jiangxi, Fujian, Taiwan, Hunan, Hubei, Guizhou, Sichuan, Yunnan, Shaanxi, Gansu, Ningxia, Xizang, Qinghai and Chongqing. Foreign countries spread throughout Eurasia.

In the summer, big brown bats roost in a variety of different shelters, including shed roofs, broad buildings, wall walls, wooden water towers, etc., but not only choose buildings, but also roost in rock gaps. In addition to the requirements of darkness, suitable temperature, quiet and other conditions are also more strict. Winter habitat is unknown.

Large brown bats live in a variety of habitats, including caves, rock crevices, eaves of houses, and gaps in doors, Windows, and walls. It mainly emits short, wide-band echolocation sound waves, which feed on coleoptera insects and also prey on diptera insects. There are four subspecies in China, namely Eptesicus serotinus pallens, E. s. andersoni, E. s. horikawai, and E. s. turcomanus. Although large brown bats are widely distributed in China, the population is small and relatively rare.

      Large brown bats live in groups, and different species can also live in the same place, generally composed of dozens to hundreds of groups, crawling on the roof of the wood or beam cracks or upside down hanging on the beam. Big brown bats have memory ability, when flying out into the hole, do not make a sound, when flying out immediately with the net to plug the hole door, when flying back, he does not make a sound, they only remember the hole is open, high speed fly back into the net.

      The big brown bat is extremely sensitive to light, second only to the water myoetis bat, in the dark period according to the sun or the season and different control of its body physiological and biochemical functions, the big brown bat this according to the sun or the season to control the physiological habits and functions of animals, obviously with the number of daylight exposure and reproduction, so called short-day animals.

The big brown bat flies to feed at sunset, dusk or dawn, when the night is wide, mainly to feed on large coleoptera insects, but also to eat diptera insects. Whenever the color of the screen falls, the big brown bat flies out of the habitat and up and down, dramatically changing the direction of flight to form a gamo-like flying shape, seemingly flying in a disorderly manner, but actually chasing insects for food. Perform full-body tricks in the air, sometimes turning 360 degrees. When flying, it constantly emits sound waves from its throat and nose, so its nose is a sonar "transmitter". The big brown bat can emit 50 sets of ultrasonic pulses per second, and can accurately receive and distinguish the same number of echoes, can quickly determine the distance and size of objects, and can detect the appearance and position of several targets. Any insect that is pronounced below the key of C can avoid being caught by it. Mosquitoes sound D to F, which is equivalent to G, and are easy to catch. The big brown bat can hunt a dozen insects a minute.

      The wintering site of the big brown bat is unknown, and it probably does not migrate long distances.

       After mating in short daylight in autumn, the eggs are not fertilized immediately, and the sperm cells are kept in the female's fallopian tube until the next spring, when food (insects) appear, fertilization begins to break, and the embryo develops. Giant brown bat cubs, which crawl without opening their eyes after giving birth, cannot fly and live on Suckling.

     Listed on the International Union for Conservation of Nature (IUCN) 2008 Red List of Threatened Species ver 3.1 - Not Threatened (LC).