Phyllostomus hastatusgreater spear-nosed bat

Geographic Range

Greater spear-nosed bats are found from eastern Central America to southern South America. They are also found in Trinidad, Tobago Islands and Margarita Islands. There are two subspecies of Phyllostomus hastatus; P. hastatus hastatus is found in Trinidad, Bolivia and southeast Brazil, and P. hastatus panamensis is found in Honduras and the Andes. (Eisenberg, 1989; Jones and Carter, 1976)

Habitat

Greater spear-nosed bats occupy several habitats, including deciduous forests, man-made clearings and tropical evergreen forests. They preferentially roost in caves. Greater spear-nosed bats are usually found below 500 m but have also been found at elevations as high as 1,394 m. (Eisenberg, 1989)

  • Other Habitat Features
  • caves
  • Range elevation
    1394 (high) m
    4573.49 (high) ft
  • Average elevation
    500 m
    1640.42 ft

Physical Description

Greater spear-nosed bats are the second largest American bat species. Vampyrum spectrum is larger. The ventral and dorsal surface fur is short and ranges from dark brown, black brown, reddish brown or greyish brown. The membranes, ears and face are black. The tips of the ears have a triangular shape and the tail is short. They have a simple and well developed nose leaf and the lower lip has a V-shaped groove. The spear-nosed bat shows sexual dimorphism. Male and female spear nosed bat skulls are most distinguishable by the greatest width of the skull (mastoid breadth), and secondarily most distinguishable by the breadth across upper canines, with males being greater in both characteristics. Males have a chest gland at the base of their throat, while the chest gland in females is amorphous. Males have greater wing loading than females, but females have a greater wingspan than males. The average wingspan of females is approximately 546 mm, while males have a slightly shorter average wingspan of 537 mm. The average length of the forearm is 84 mm in males and 82 mm in females. Total length of the body from head to tail is approximately 131 mm in males and 126 mm in females. The average mass of adult males is 104 g while adult females are 87 g. The glandular throat sac is more developed in males. The dental formula is I 2/2, C 1/1, P 2/2 and M 3/3. Phyllostomus discolor and Phyllostomus elongatus are closely related species that occur in the same range as greater spear-nosed bats. But both species are smaller than greater spear-nosed bats. The pelage of Phyllostomus discolor has white tips and the wings of Phyllostomus elongatus have white tips. The basal metabolic rate of greater spear-nosed bats is 1.19 ccO2/g-hr. (Eisenberg, 1989; McNab, 1969; Müller-Schwarze, 1983; Stern, et al., 1997a; Willig and Hollander, 1995)

  • Range mass
    80.5 to 120.41 g
    2.84 to 4.24 oz
  • Range length
    117.87 to 137.95 mm
    4.64 to 5.43 in
  • Range wingspan
    515 to 562 mm
    20.28 to 22.13 in
  • Average basal metabolic rate
    0.559 W
    AnAge

Reproduction

Greater spear-nosed bats have a polygynous mating system, where males will compete for and defend potential mates. Harems range from 7 to 25 females with a single resident male. Pre-reproductive females will remain in a non-harem group until they mature and join a harem. Males will defend their harems by wing beating, vocalization, and even attacking approaching males. In contrast, males will not respond to females moving among harems. (McCracken and Bradbury, 1981; Santos, et al., 2003; Wilson, 1979)

Copulation begins between October and December. Females give birth to a single offspring between April and May, during the dry season, and wean the young during the wet season. The timing of birth can vary depending on seasonal rainfall levels, but the occurrence of births is highly synchronous within harems. The mass of a 1 day old spear-nosed bat is quite variable, ranging from 10.8 to 22.5 g. Other than the first few days when the mother carries its offspring on its back during foraging flights, the babies are left in their roost for about 4 weeks, remaining attached to the mother’s breast whenever she is not away from the roost. During this time, offspring triple in size. After 4 weeks, the offspring will cling to its mother’s back whenever the mother is in the roost, until it reaches 6 weeks old, at which point it begins to fly on its own within the cave or roost. Weaning occurs at about 49 days of age. At 2 months old, offspring will start to go out on evening flights. Mothers continue to lactate for approximately 3 months post-partum. Reproduction in females begins at two years of age. Greater spear-nosed bat reproduction is monoestrous in Middle America and Trinidad and polyestrous in South America. Reproduction and growth rates are highest in polyestrous populations with large harems, and are lowest in monoestrous populations with either large or small harems. The greatest restriction on population growth in both monoestrous and polyestrous opoulations of greater spear-nosed bats is pup mortality. (Boughman, 2006; McCracken and Bradbury, 1981; Mendes, et al., 2013; Porter and Wilkinson, 2001; Stern and Kunz, 1998; Stern, et al., 1997b)

  • Breeding interval
    Greater spear-nosed bats breed once a year in portions of their range and several times a year in other portions of their range
  • Breeding season
    Greater spear-nosed bats breed from October to December
  • Average number of offspring
    1
  • Average number of offspring
    1
    AnAge
  • Average gestation period
    120 days
    AnAge
  • Average weaning age
    49 days
  • Average time to independence
    2 months
  • Average age at sexual or reproductive maturity (female)
    2 years

Females within social groups exhibit alloparental care by means of “pup guarding”. When pups fall from their roost, they are retrieved by their mother. Females from the same social group as the pup and its mother will visit the fallen pup, their presence providing protection from females of a different social group that may attack fallen pups. Pups use unique isolation calls to communicate that they have fallen from their roost site. Mothers are able to discern isolation calls of their own offspring from the isolation calls of other pups. Once the young become independent, they are not recruited into their parental harems. (Bohn, et al., 2009; Bohn, et al., 2007; McCracken and Bradbury, 1981)

  • Parental Investment
  • precocial
  • female parental care
  • pre-weaning/fledging
    • protecting
      • female
  • pre-independence
    • protecting
      • female
  • extended period of juvenile learning

Lifespan/Longevity

The lifespan for Phyllostomus hastatus is 18 years. Males have higher mortality than females. (McCracken and Bradbury, 1981; Wilkinson and South, 2002)

  • Average lifespan
    Status: wild
    18 years
  • Average lifespan
    Status: captivity
    18 years
    AnAge

Behavior

Greater spear-nosed bats live either in harems, with a dominant male and many females, or in bachelor groups of many unrelated males. Tooth wear indicates that harem males are older than bachelor males. Foraging occurs most frequently at 2 to 3 hours before sunset. Harem males forage more frequently but for an overall shorter time in comparison to females. Harem males do not defend foraging areas and do not forage in the same area as their harem females. Greater spear-nosed bats typically do not forage in groups, but they do forage in near proximity to each other. Greater spear-nosed bats have a wide variety of roost types, including caves, hollow trees or logs, buildings, in or under leaves, or in hollow termite nests. The roost size can range between 3 to 585 bats when cohabiting with other bat species such as Molossus molossus and Molossus rufus. In human capture-and-release experiments, greater spear-nosed bat homing ability shows a gradual decline as the release distance from its roost increases. Most bats are able to return to their roost when released 20 km away. When individuals are released 30 km away from their roost, the percentage of greater spear-nosed bats that are able to successfully return home drops below 50%. (Costa, et al., 2010; Kunz, et al., 1998; McCracken and Bradbury, 1981; Tuttle, 1976)

Home Range

Greater spear-nosed bats typically forage as much as 10 km away from their roost. (Williams and Williams, 1970)

Communication and Perception

In addition to echolocation, where frequencies are 32 to 55 kHz, greater spear-nosed bats also use vocal, lower frequency communication in the vicinity of 6 to 12 kHz. Screech calls allow group-specific recognition to allow for coordination when foraging outside caves. These screech calls can be used to recruit conspecifics to foraging areas. Greater spear-nosed bats vision for orientation once objects are detected using sound localization. (Koay, et al., 2002; Wilkinson and Boughman, 1998)

Food Habits

Greater spear-nosed bats are omnivorous. Their diets consist mostly of insects, but also include fruits, nectar and pollen. Greater spear-nosed bats may be one of the only bat species with the ability to remove the shell of the jackfruit (Artorcarpus heterophyllus) and eat the fleshy inside while it remains attached to the tree. Because jackfruit is available year-round, greater spear-nosed bats may feed on this fruit when other food resources are low. Other fruiting plants that are consumed by greater spear-nosed bats are Cecropia species, Piper species, Solanum species, and Vismia species. Greater spear-nosed bats have been documented eating mice (Mus musculus), birds (Cyanerpes cyaneus), and even other bats, such as Hemiderma perspicillatum. (Brosset, et al., 1996; Dunn, 1933; Raíces, et al., 2008; Willig, et al., 1993)

  • Animal Foods
  • birds
  • mammals
  • insects
  • Plant Foods
  • seeds, grains, and nuts
  • fruit
  • nectar
  • pollen

Predation

Predators of juvenile greater spear-nosed bats include screech owls (Otus choliba), bullfrogs (Lithobates catesbeianus), tegu lizards (Tupinambis teguixin) and opossums (Didelphis virginiana). Pup survival drops dramatically following first flight and 40% of juvenile spear-nosed bats do not survive to independence, possibly as a result of predation, parasites, or from not being retrieved after falling from cave ceilings. (Boughman, 2006; Stern and Kunz, 1998)

Ecosystem Roles

Greater spear-nosed bats have a variable diet that includes fruit and nectar. They are important pollinators in many plants, one of which is Ceiba pentandra, a large flowering tree. Because both greater spear-nosed bats and Phyllostomus discolor may forage in the same tree, resource exploitation results in their frequent movement between Ceiba pentandra, promoting cross pollination. Greater spear-nosed bats also promote pollination when they forage across large distances. Greater spear-nosed bats act as a reservoir for multiple parasites. Trichobius longipes is an ectoparasite that is found more frequently in female spear-nosed bats than males. This sex bias in parasite infection may be explained by the more stable host environment that females provide, as they typically stay in the same roost all year, while males tend to travel between roosts more often. (Azevedo, et al., 2002; Esbérard, et al., 2014; Gribel, et al., 1999; McCracken and Bradbury, 1981; Santos, et al., 2009; Williams and Williams, 1970)

  • Ecosystem Impact
  • disperses seeds
  • pollinates
Commensal/Parasitic Species

Economic Importance for Humans: Positive

Greater spear-nosed bats may be involved in the recovery of ecosystems affected by deforestation in French Guiana. Greater spear-nosed bats contribute to recolonization of Cecropia species, Piper species, Solanum species, and Vismia species, which are pioneer plants that thrive in the large forests gaps left by habitat disturbance, and are critical for successful regeneration of later successional species that constitute complex forests. Seed dispersal of these tree specices by greater spear-nosed bats leads to habitat expansion and recolonization. (Brosset, et al., 1996)

Economic Importance for Humans: Negative

Greater spear-nosed bats are vectors for transmission of Trypanosoma cruzi, the causative agent of Chagas’ Disease that uses mammalian hosts, including humans. Chagas’ disease is prevalent in North, Central, and South America, and is life-long in its impacts. (Lisboa, et al., 2008; Moncayo and Silveira, 2009)

  • Negative Impacts
  • injures humans
    • carries human disease

Conservation Status

Greater spear-nosed bats are listed as Least Concern (LC) under the IUCN. However, monoestrous populations have low reproductive rates and also live within Central America, a biological hotspot that globally has the second highest number of endemic vertebrates next to the Tropical Andes and has experienced severe habitat loss due to humans. Therefore, greater spear-nosed bats should be carefully monitored in areas undergoing disturbances to ensure that populations remain stable. (Mendes, et al., 2013; Myers, et al., 2000)

Contributors

Sandhya Boyd (author), University of Manitoba, Jane Waterman (editor), University of Manitoba, Tanya Dewey (editor), University of Michigan-Ann Arbor.

Glossary

Neotropical

living in the southern part of the New World. In other words, Central and South America.

World Map

acoustic

uses sound to communicate

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

crepuscular

active at dawn and dusk

echolocation

The process by which an animal locates itself with respect to other animals and objects by emitting sound waves and sensing the pattern of the reflected sound waves.

ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

omnivore

an animal that mainly eats all kinds of things, including plants and animals

polygynous

having more than one female as a mate at one time

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

sexual ornamentation

one of the sexes (usually males) has special physical structures used in courting the other sex or fighting the same sex. For example: antlers, elongated tails, special spurs.

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

ultrasound

uses sound above the range of human hearing for either navigation or communication or both

visual

uses sight to communicate

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

young precocial

young are relatively well-developed when born

References

Azevedo, A., P. Linardi, M. Coutinho. 2002. Acari Ectoparasites of Bats from Minas Gerais, Brazil. Journal of Medical Entomology, 39/3: 553-555.

Bohn, K., C. Moss, G. Wilkinson. 2009. Pup guarding by greater spear-nosed bats. Behavioural Ecology and Sociobiology, 63: 1693-1703.

Bohn, K., G. Wilkinson, C. Moss. 2007. Discrimination of infant isolation calls by female greater spear-nosed bats, Phyllostomus hastatus. Animal Behaviour, 73: 423-432.

Boughman, J. 2006. Selection on social traits in greater spear-nosed bats, Phyllostomus hastatus. Behavioural Ecology and Sociobiology, 60: 766-777.

Brosset, A., P. Charles-Dominique, A. Cockle, J. Cosson, D. Masson. 1996. Bat communities and deforestation in French Guinana. Canadian Journal of Zoology, 74: 1974-1982.

Costa, L., E. Lourenço, C. Esbérard, R. Silva. 2010. Colony size, sex ratio and cohabitation in roosts of Phyllostomus hastatus (Pallas) (Chiroptera: Phyllostomidae). Brazilian Journal of Biology, 70/4: 1047-1053.

Dunn, L. 1933. Observations on the Carnivorous Habits of the Spear-Nosed Bat, Phyllostomus Hastatus. Journal of Mammology, 14/3: 188-199.

Eisenberg, J. 1989. Mammals of the Neotropics. Chicago: The University of Chicago Press.

Esbérard, E., T. Biavatti, W. Carvalho, L. Costa, M. Godoy, L. Gomes, J. Luz, A. Pol, E. Silva, G. Tato, G. Graciolli. 2014. Trichobius longipes (Diptera, Streblidae) as a parasite of Phyllostomus hastatus (Chiroptera, Phyllostomidae). Brazilian Journal of Veterinary Parasitology, 23/3: 315-319.

Gribel, R., P. Gibbs, A. Queiroz. 1999. Flowering Phenology and Pollination Biology of Ceiba pentandra (Bombacaceae) in Central Amazonia. Journal of Tropical Ecology, 15/3: 247-263.

Heffner, R., G. Koay, H. Heffner.. 2007. Sound-localization acuity and its relation to vision in large and small fruit-eating bats: I. Ecolocating Species, Phyllostomus hastatus and Carollia perspicillata. Hearing Research, 234: 1-9.

Jones, J., D. Carter. 1976. ANNOTATED CHECKLIST, WITH KEYS TO TO SUBFAMILIES AND GENERA. Pp. 13 in R Baker, J Jones, D Carter, eds. Biology of Bats of the New World Family Phyllostomatidae. Part I. Texas: Texas Tech University Press.

Koay, G., K. Bitter, H. Heffner, R. Heffner. 2002. Hearing in American leaf-nosed bats. I: Phyllostomus hastatus. Hearing Research, 171: 96-102.

Kunz, T., S. Robson, K. Nagy. 1998. Economy of Harem Maintenance in the Greater Spear-Nosed Bat, Phyllostomus hastatus. Journal of Mammology, 79/2: 631-642.

Lisboa, C., A. Pinho, H. Herrera, M. Gerhardt, E. Cupolillo, A. Jansen. 2008. Trypanosoma cruzi (kinteoplastida, Trypanosomatidae) genotypes in neotropical bats in Brazil. Veterinary Parasitology, 156: 314-318.

McCracken, G., J. Bradbury. 1981. Social Organization and Kinship in the Polygynous Bat Phyllostomus hastatus. Behavioural Ecology and Sociobiology, 8: 11-34.

McNab, B. 1969. THE ECONOMICS OF TEMPERATURE REGULATION IN NEOTROPICAL BATS. Comparative Biochemistry and Physiology, 31: 227-268.

Mendes, P., M. Oprea, D. Brito. 2013. Family Planning: Does Variation in Reproductive Strategies Affect Vulnerability to Extinction in the Greater Spear-nosed Bat Phyllostomus Hastatus?. Acta Chiropterologica, 15/2: 365-369.

Moncayo, Á., A. Silveira. 2009. Current epidemiological trends for Chagas disease in Latin America and future challenges in epidemiology, surveillance and health policy. Memórias do Instituto Oswaldo Cruz, 104: 17-30.

Myers, N., R. Mittermeier, C. Mittermeier, G. da Fonseca, J. Kent. 2000. Biodiversity hotspots for conservation priorities. Nature, 403: 853-858.

Müller-Schwarze, D. 1983. Scent Glands in Mammals and Their Function. Pp. 156 in J Eisenberg, D Kleiman, eds. Advances in the Study of Mammalian Behaviour. Pennsylvania: American Society of Mammologists.

Porter, T., G. Wilkinson. 2001. Birth synchrony in greater spear-nosed bats (Phyllostomus hastatus). Journal of Zoology (London), 253/3: 383-390.

Raíces, D., F. Pessôa, J. Luz, T. Jordão-Nogueira, C. Esbérard, H. Bergallo. 2008. Feeding behaviour of the bat Phyllostomus hastatus (Pallas 1767) in jackfruit Artocarpus heterophyllus Lamarck (Moraceae), in Ilha Grande, Rio de Janeiro State, Brazil. Revista Brasileira de Zoociências, 10/3: 265-267.

Santos, C., P. Dias, F. Rodrigues, K. Lobato, L. Rosa, T. Oliveira, J. Rebêlo. 2009. Moscas Ectoparasitas (Diptera: Streblidae) de Morcegos (Mammalia: Chiroptera) do Município de São Luís, MA: Taxas de Infestação e Associações Parasito-Hospedeiro. Neotropical Entomology, 38/5: 595-601.

Santos, M., L. Aguirre, L. Vázquez, J. Ortega. 2003. Mammalian Species Phyllostomus hastatus. American Society of Mammalogists, 722: 1-6.

Stern, A., T. Kunz. 1998. Intraspecific Variation in Postnatal Growth in the Greater Spear-Nosed Bat. Journal of Mammology, 79/3: 755-763.

Stern, A., T. Kunz, S. Bhatt. 1997. SEASONAL WING LOADING AND THE ONTOGENY OF FLIGHT IN PHYLLOSTOMUS HASTATUS (CHIROPTERA: PHYLLOSTOMIDAE). Journal of Mammology, 78/4: 1199-1209.

Stern, A., T. Kunz, E. Studier, O. Oftedal. 1997. Milk Composition and lactational output in the greater spear-nosed bat, Phyllostomus hastatus. Journal of Comparative Physiology B, 167: 389-398.

Tuttle, M. 1976. Collecting Techniques. Pp. 77 in R Baker, J Jones, D Carter, eds. Biology of Bats of the New World Family Phyllostomatidae. Part I. Texas: Texas Tech University Press.

Wilkinson, G., J. Boughman. 1998. Social calls coordinate foraging in greater spear-nosed bats. Animal Behaviour, 55: 337-350.

Wilkinson, G., J. South. 2002. Life history, ecology and longevity in bats. Aging Cell, 1: 124-131.

Williams, T., J. Williams. 1970. Radio Tracking of Homing and Feeding Flights of Neotropical Bat, Phyllostomus hastatus. Animal Behaviour, 18: 302-309.

Willig, M., G. Camilo, S. Noble. 1993. Dietary Overlap in Frugivorous and Insectivorous Bats from Edaphic Cerrado Habitats of Brazil. Journal of Mammology, 74/1: 117-128.

Willig, M., R. Hollander. 1995. Secondary Sexual Dimorphism and Phylogenetic Constraints in Bats: A Multivariate Approach. Journal of Mammalogy, 76/4: 981-992.

Wilson, D. 1979. Biology of Bats of the New World Family Phyllostomatidae. Part III.. Texas: Texas Tech University Press.