Pale Spear-nosed Bat, Phyllostomus discolor
The pale spear-nosed bat (Phyllostomus discolor) is native to Central and South America. Its range extends from southern Mexico to Peru, and throughout southeastern Brazil. It can also be found in Bolivia and Paraguay. There is a controversial thought that it occurs in Argentina, but this is based off only one individual that has actually disappeared. It prefers a habitat within agricultural areas and lowland forests at an altitude of up to 2,000 feet. The pale-spear nosed bat holds two subspecies, but it is not yet known if they are truly subspecies or distinct species.
The pale-spear nosed bat can reach an average body weight between 3.1 and 4.3 inches, with an average wingspan of up to seventeen inches. These bats vary in weight depending on sex, with males weighing an average of 1.6 ounces and females weighing an average of 1.4 ounces. It can vary in color from lighter brown to nearly black, but the underbelly is typically paler gray or white in color. The nose leaf on this bat is prominent, as are the ears, which are able to reach the tip of the nose when extended forward. Males bear a glandular sac on the throat, and although females bear the same gland, it is nearly undetectable.
As is typical with bat species, the pale spear-nosed bat is nocturnal and will roost in caves or trees during the day. Colonies of up to 400 individuals have been recorded. Within these colonies, smaller groups are formed either by all males or by one male with up to fifteen females. These are known as harem groups, and females will move between groups depending on the actions of the males. The females within one small group are close and will groom each other but are aggressive towards foreign females.
Mating season for the pale spear-nosed bat varies depending on location. In Brazil, it is thought that these bats can mate year round, while in Guatemala mating season is restricted to summer. Typically, females will mate with the male that leads her harem group, but foreign males have been known to chase and mate with females not in his group.
Pups of this species are born mostly hairless, although it does bear whiskers and some hair on the membrane that stretches between the legs. Mothers will carry the pups while they forage for the first few days of its life. After this, the pups are left at the roost, where their roost mates tolerate them. Occasionally, pups may cling to harem males. Pups are capable of flying at five to six weeks and are weaned at three months of age.
The pale spear-nosed bat is omnivorous, feeding primarily on pollen, flowers, and nectar. These bats are known pollinators, specifically of sorai trees. In some areas of its range, the pale spear-nosed bat has been known to eat a large amount of insects, although plant materials do make up the majority of their diet. It is thought that in some cases, pollen is consumed in the dry season, while insects are consumed in the rainy season. These bats have been known to forage in groups of up to twelve individuals, flying in a line and taking turns at flowers until all of the pollen has been eaten.
The pale spear-nosed bat is able to distinguish objects by using echolocation in a way that is separate from the actual size of the object. It is thought that this ability may not be restricted to this species, but their behaviors are well documented. They are able to make twenty distinct vocalizations, but males will also communicate by using scent markings. The pale spear-nosed bat appears on the IUCN Red List with a conservation status of “Least Concern.”
Image Caption: Pale spared-nose bat, Phyllostomus discolor, picture taken in La Selva, Costa Rica. Credit: Felineora/Wikipedia(CC BY 3.0)