Greater Spear-nosed Bat, Phyllostomus hastatus
The greater spear-nosed bat (Phyllostomus hastatus) is a member of the Phyllostomidae family that can be found in central and South America. Its range stretches from Guatemala and Belize to Peru, Paraguay, Bolivia, Brazil, and northern Argentina in the south. It can also be found on Margarita Island in Venezuela and in Trinidad and Tobago. These bats prefer to reside in areas with abundant water, but they have been found in regions that are more arid and in open or forested areas.
The greater spear-nosed bat can reach an average body length between 3.9 and 5.1 inches, with a wingspan of 1.4 feet. Although it is considered a large bat in its range, it weighs an average of only 2.9 ounces. Its thick fur is typically dark brown in color with an orange shade on the underbelly. The species gets its common name from the protruding spear shaped nose, which is dark in color. Both females and males bear a throat sac, but this is more pronounced in males.
The greater spear-nosed bat typically forms groups between ten to one hundred individuals, and there are subgroups within these colonies. One alpha male can lead a harem group of up to thirty females, although the typical number of female individuals is eighteen. Any females or males that do not belong to a harem group, up to eighty percent of the colony, will form their own separate bachelor groups. These bats prefer to roost in caves, termite mounds, hollow trees, and thatched roofs.
McCracken and Bradbury, who have studied the greater spear-nosed bat and its social structures, have concluded that the most likely reason behind these social structures is for increased organization and safety while foraging. When one bat locates food, it will call to its roost mates alerting them to the find. This is supported by Wilkinson who noted similar behaviors in 1995.
The foraging areas of this bat depend on their social structure as well, with alpha males foraging closer to the roost and bachelor males flying as far as 5.5 miles for food. The greater-spear bat eats more fruit, insects, and pollen than vertebrates, which is not typical to members of its family.
There is no distinct mating season for the greater spear-nosed bat, as lactating females have been recorded year round. Although it is thought that this bat only mates once a year, the frequent occurrence of lactating females may mean that it is able to mate at least twice a year. Each birth only consists of one pup, and their reproduction rate is low.
The greater spear-nosed bat is known for being both beneficial and slightly harmful to humans. It eats insects that humans consider pests and helps pollinate crops, but it does cause some destruction to fruit crops like bananas. There are currently no major threats to this species of bat, although there is growing concern about habitat destruction. The greater spear-nosed bat appears on the IUCN Red List with a conservation status of “Least Concern”.
Image Caption: Greater Spear-nosed Bat, picture taken in La Selva, Costa Rica. Credit: Felineora/Wikipedia(CC BY 3.0)