Leptonycteris yerbabuenaelesser long-nosed bat

Geographic Range

Arid and semi-arid regions of Mexico and southwestern United States, including the Sonoran Desert. (Ceballos, et al., November 1997)

Habitat

Leptonycteris yerbabuenae is found near cacti, usually living in caves in huge groups. The habitat ranges from desert scrub in the southwestern United States and northern Mexico to high elevations on wooded mountains further south in Mexico.

  • Other Habitat Features
  • caves

Physical Description

Leptonycteris yerbabuenaee is a yellow-brown or cinnamon gray bat, with a total head and body measurement of approximately 3 inches (7.62 cm). The tongue measures approximately the same length as the body. This species also has a small noseleaf. The wingspan of Leptonycteris yerbabuenae is approximately 10 inches (25 cm) and the mass is roughly 23 g. (Snyder and Tyler, 1997; Southwest Center Species Database, October 15, 1997)

  • Sexual Dimorphism
  • sexes alike
  • Average mass
    23 g
    0.81 oz
  • Average length
    8 cm
    3.15 in
  • Average wingspan
    25 cm
    9.84 in

Reproduction

Little is known about the mating system and behavior of lesser long-nosed bats. It is known, however, that females converge on maternity colonies to birth and care for their young (Ceballos et al. 1997). (Ceballos, et al., November 1997)

Little is known about the reproductive behavior of lesser long-nosed bats. It is hypothesized that the gestation period is approximately five months. It is not known whether gestation involves delayed implantation or delayed development. There are different mating/birthing schedules for different populations. In southern Mexico, females give birth in December or January; in Baja California, babies are born in March (Ceballos et al. 1997).

There is only one pup per litter. This bat is not bimodally polyestrous (it does not give birth twice a year). Sperm production is maximal during the late wet season (Ceballos et al. 1997). (Ceballos, et al., November 1997)

  • Breeding interval
    Breeding occurs once yearly.
  • Breeding season
    Breeding season varies regionally.
  • Average number of offspring
    1
  • Average gestation period
    5 months

Females converge on maternity colonies, which consist of anywhere from several thousand to over one hundred thousand pregnant animals. The females do not come to the colony at the same time or during the same stage of pregnancy. The births are generally spread out over a one-month period. In the northern Sonoran Desert and in Arizona, females converge on the maternity colonies in mid- to late-April. This timing varies by population (Ceballos et al. 1997).

Each female cares for her single pup alone. In the maternity colonies, no attempts are made by mothers to nurse or feed others' babies. They do, however, exhibit other behaviors, such as visiting, touching and nosing others' pups several times per night (Ceballos et al. 1997).

The young begin to fly at approximately four weeks of age (Ceballos et al. 1997). (Ceballos, et al., November 1997)

  • Parental Investment
  • altricial
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female

Behavior

Lesser long-nosed bats exhibit many characteristic behaviors, including gregarious roosting, no cooperative/social bonding, unexpected sleeping patterns, and local and long distance migration along nectar trails/corridors (Fleming et al. 1998).

Lesser long-nosed bats spend over half of their lives in a dayroost, leaving only to forage at night. They spend most of their time in the dayroost resting, digesting food, interacting with other individuals, mating and caring for young. Individuals of this species form extremely large colonies, including tens of thousands to over one hundred thousand animals, in caves which trap metabolic heat. This metabolic heat reduces the energetic cost to females and increases growth rates in the young. In these colonies, the adults are fairly passive; there is a low frequency of interactions among females, and between females and their young. The most frequent behavior is nosing other individuals. This species is non-cooperative; they do not exhibit socially cooperative behavior like allogrooming, and females have only been seen to nurse their own young (Fleming et al. 1998).

Although lesser long-nosed bats rest during the day and do not actively move or fly, this chiropteran is usually fully awake and alert. For reasons yet unknown, this species sleeps much less than is predicted by its body size and metabolic rate (Fleming et al. 1998).

Members of this species also tend to migrate along a nectar trail or corridor, following the availability of food resources. This behavior is exhibited especially in the northern region of the bat's range, where resources are not available year-round. The females also migrate when they converge on maternity colonies near the end of their pregnancies (Rojas-Martinez et al. 1999). (Fleming, et al., February 1998; Rojas-Martinez, et al., 1999)

Communication and Perception

Food Habits

The diet of lesser long-nosed bats consists of nectar and pollen from the night-blooming flowers of the Agavaceae, Bombaceae, Cactaceae, Convolvulaceae and Leguminosae. They also feed on the pulp of cactus fruit. They are not obligate cactus visitors. The diet is influenced by availability of possible food resources (Ceballos et al. 1997).

Lesser long-nosed bats forage at night, between 24:00 and 02:00, when flowers have accumulated substantial amounts of nectar. These bats begin by taking generally long commuting flights to a foraging area. Once they arrive at the foraging area (which usually consists of about one square kilometer), they survey many plants. Later, they may make return visits to several of those plants to feed (Horner et al. 1998).

  • Plant Foods
  • fruit
  • nectar

Ecosystem Roles

This species has a very close relationship with the cacti on which it feeds. Since lesser long-nosed bats are nectarivores with a relatively large foraging area, feeding results in both short and long distance pollen movements. By doing so, these bats help to create gene flow within and between populations of columnar cacti (Horner et al. 1998).

Through fecal analysis, it has been shown that this species also disperses the seeds of fruit on which it feeds (Rojas-Martinez et al. 1999).

  • Ecosystem Impact
  • disperses seeds
  • pollinates

Economic Importance for Humans: Positive

Lesser long-nosed bats help to pollinate agave, from which tequila is made (Arita and Wilson, 1987). (Arita and Wilson, December 1987)

  • Positive Impacts
  • pollinates crops

Conservation Status

Leptonycteris yerbabuenae is considered an endangered species in North America. Destruction of its primary food resources and general habitat by the tequila industry and agriculture is threatening its population numbers. This species is also especially vulnerable to extinction because it is a specialist, feeding on the nectar, pollen and fruit of several plant families present in southern North America and Central America. It is also especially susceptible because of its migratory habits. Conservation efforts should include food resources, roosting sites and protection of habitats along the migratory route (Arita and Santos-Del-Prado, 1999). (Arita and Santos-Del-Prado, February 1999)

Temperate North American bats are now threatened by a fungal disease called “white-nose syndrome.” This disease has devastated eastern North American bat populations at hibernation sites since 2007. The fungus, Geomyces destructans, grows best in cold, humid conditions that are typical of many bat hibernacula. The fungus grows on, and in some cases invades, the bodies of hibernating bats and seems to result in disturbance from hibernation, causing a debilitating loss of important metabolic resources and mass deaths. Mortality rates at some hibernation sites have been as high as 90%. While there are currently no reports of Leptonycteris yerbabuenae mortalities as a result of white-nose syndrome, the disease continues to expand its range in North America. (Cryan, 2010; National Park Service, Wildlife Health Center, 2010)

Other Comments

Leptonycteris yerbabuenae was previously known as a subspecies: L. curasoae yerbabuenae. In older literature, this species has sometimes been referred to as L. sanborni.

Contributors

Jasmine Bhatia (author), University of Michigan-Ann Arbor, Ondrej Podlaha (editor), University of Michigan-Ann Arbor.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

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.

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

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.

frugivore

an animal that mainly eats fruit

herbivore

An animal that eats mainly plants or parts of plants.

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).

migratory

makes seasonal movements between breeding and wintering grounds

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.

nectarivore

an animal that mainly eats nectar from flowers

nocturnal

active during the night

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

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

social

associates with others of its species; forms social groups.

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

tropical

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

viviparous

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

References

Arita, H., D. Wilson. December 1987. Long-nosed Bats and Agaves: The Tequila Connection. Bats, 5: 3-5.

Arita, H., K. Santos-Del-Prado. February 1999. Conservation biology of nectar-feeding bats in Mexico. Journal of Mammalogy, 80: 31-41.

Bat Conservation International, 2001. "BCI-Bat Species: US Species: *Leptonycteris curasoae*" (On-line). Accessed October 7, 2001 at http://www.batcon.org/discover/species/lcuraso.html.

Ceballos, G., T. Fleming, C. Chavez, J. Nassar. November 1997. Population dynamics of *Leptonycteris curasoae* (Chiroptera: Phyllostomidae) in Jalisco, Mexico. Journal of Mammalogy, 78: 1220-1230.

Cryan, P. 2010. "White-nose syndrome threatens the survival of hibernating bats in North America" (On-line). U.S. Geological Survey, Fort Collins Science Center. Accessed September 16, 2010 at http://www.fort.usgs.gov/WNS/.

Fleming, T., A. Nelson, V. Dalton. February 1998. Roosting behavior of the lesser long-nosed bat, *Leptonycteris curasoae*. Journal of Mammalogy, 79: 147-155.

Horner, M., T. Fleming, C. Sahley. 1998. Foraging behaviour and energetics of a nectar-feeding bat, *Leptonycteris curasoae* (Chiroptera: Phyllostomidae). Journal of Zoology, London, 244: 575-586.

National Park Service, Wildlife Health Center, 2010. "White-nose syndrome" (On-line). National Park Service, Wildlife Health. Accessed September 16, 2010 at http://www.nature.nps.gov/biology/wildlifehealth/White_Nose_Syndrome.cfm.

Rojas-Martinez, A., A. Valiente-Banuet, M. del Coro Arizmendi, A. Alcantara-Eguren, H. Arita. 1999. Seasonal distribution of the long-nosed bat (*Leptonycteris curasoae*) in North America: does a generalized migration pattern really exist?. Journal of Biogeography, 26: 1065-1077.

Snyder, H., M. Tyler. 1997. "Lesser Long-Nosed Bat" (On-line). Accessed October 7, 2001 at http://www.animalfirm.com/bat.html.

Southwest Center Species Database, October 15, 1997. "Lesser Long-Nosed Bat" (On-line). Accessed October 7, 2001 at http://www.sw-center.org/swcbd/dbase/llnbat.html.