The Greater Spear-nosed Bat, Phyllostomus hastatus, is a bat

Bat

Bats are mammals of the order Chiroptera "hand" and pteron "wing") whose forelimbs form webbed wings, making them the only mammals naturally capable of true and sustained flight. By contrast, other mammals said to fly, such as flying squirrels, gliding possums, and colugos, glide rather than fly,...

 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of the family Phyllostomidae from South

South America

South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 and Central America

Central America

Central America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...

. It is one of the larger bats of this region, and is omnivorous.

Habitat

Phyllostomus hastatus lives in tropical regions of the Americas

Americas

The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

. The species ranges from Guatemala

Guatemala

Guatemala is a country in Central America bordered by Mexico to the north and west, the Pacific Ocean to the southwest, Belize to the northeast, the Caribbean to the east, and Honduras and El Salvador to the southeast...

 and Belize

Belize

Belize is a constitutional monarchy and the northernmost country in Central America. Belize has a diverse society, comprising many cultures and languages. Even though Kriol and Spanish are spoken among the population, Belize is the only country in Central America where English is the official...

 south to Peru

Peru

Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

, Bolivia

Bolivia

Bolivia officially known as Plurinational State of Bolivia , is a landlocked country in central South America. It is the poorest country in South America...

, Paraguay

Paraguay

Paraguay , officially the Republic of Paraguay , is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. Paraguay lies on both banks of the Paraguay River, which runs through the center of the...

, northern Argentina

Argentina

Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

 and Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

. It also occurs in Trinidad and Tobago

Trinidad and Tobago

Trinidad and Tobago officially the Republic of Trinidad and Tobago is an archipelagic state in the southern Caribbean, lying just off the coast of northeastern Venezuela and south of Grenada in the Lesser Antilles...

 and on Margarita Island (Venezuela)

Isla Margarita

Margarita Island is the largest island of the state of Nueva Esparta in Venezuela, situated in the Caribbean Sea, off the northeastern coast of the country. The state also contains two other smaller islands: Coche and Cubagua. The capital city of Nueva Esparta is La Asunción, located in a river...

. Although most commonly found around streams and other bodies of water, these bats are also present in drier areas. They inhabit both open and forested regions.

Appearance

The Greater Spear-nosed Bat has a body length of around 100–130 mm (3.9–5.1 in), with a wing span of 455 mm (17.9 in). Despite the large size, it is very light, weighing on average 81 g (2.9 oz). Its long, thick hair is dark brown, with a slight orange tinge on the ventral side. It has a well-developed nose shaped like a spear-head, which gives it its more common name. The ears are spread far apart and are smaller than in other phyllostomids. The lower lip has a distinctive V-shaped groove and many warts. Both sexes have a thoat sac just above breast bone. That of the male is enlarged, while the female's is much smaller and simpler.

Feeding

P. hastatus sometimes eats vertebrates, but much less so than other phyllostomids. It is omnivorous, most commonly feeding on fruit, pollen and insects. Vertebrates comprise a minor part of its diet. Norberg and Fenton (1988) speculate that this is due to its "higher aspect ratio and wing loading". P. hastatus has an extremely sensitive sense of smell. When foraging for food, it can locate hidden pieces of banana amongst the leaf litter on the forest floor.

Echolocation

P. hastatus has a broad bandwidth call that enables it to resolve distances almost as small as 4 mm. This implies that it can distinguish echoes as little as 20 microseconds apart.

Group structure

P. hastatus roosts in caves, hollows in trees, termite mounds and thatched roofs. It lives in groups of between ten and a hundred. Within this group there may be several subgroups, as one dominant male presides over a group of up to thirty females. The average harem size is eighteen. The dominant male may be in control of the harem for many years. The remaining 80% of males and young females form their own large bachelor group to complete the colony. Studies by McCracken and Bradbury (1977) have shown that unrelated females in the colony often form stable factions.

McCracken and Bradbury considered many possible reasons for group formation in P. hastatus. The most plausible are thought to be co-operation in foraging for food, and protection and defence while feeding. Once food is found, a successful bat forager alerts others in the feeding group to the location. This was also found by Wilkinson (1995), who noted that P. hastatus call on the other members of the group when finding food, in the absence of territorial calls. Feeding groups may be segregated by social status. Dominant males have feeding sites close to the roost, while single males may have to fly as far as 9 km in order to find a feeding site.

Reproduction

The pattern of reproduction in P. hastatus may vary over its range. Although this bat generally only reproduces once a year, lactating females have been found throughout the year, suggesting that some may reproduce more often. They give birth to only one young at a time. The reproduction rate is very low. Even with a change of the dominant male, constancy is almost always maintained. McCracken and Bradbury (1977, 1981) characterized the reproduction cycle of P. hastatus as follows:

February – April; pregnancy

Pregnancy

Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...

 

May – mid-July; lactation

Lactation

Lactation describes the secretion of milk from the mammary glands and the period of time that a mother lactates to feed her young. The process occurs in all female mammals, however it predates mammals. In humans the process of feeding milk is called breastfeeding or nursing...

 

Mid-July – late October; anoestrous 

Late October – February; oestrous


It has been hypothesized that it is females that eat vertebrates, to provide protein for lactation.

Economic importance

The activities of P. hastatus are both beneficial and costly to humans. They feed on insects and other pests that could harm crops, and they help pollinate many crops. However, they also consume some crops, such as bananas. Although they are not endangered, there is concern over destruction of their habitat.