Mexican Long-tongued Bat

The Mexican long-tongued bat is a nectar-feeding bat found from the southwestern United States through Mexico into Central America. It is remarkable for its elongated snout and extensible tongue, adaptations that allow it to feed on nectar from cacti and agave flowers, making it an important pollinator. This species undertakes seasonal movements tied to the blooming of its food plants, appearing in the U.S. only during warmer months.

Southwestern United States, Mexico, and Central America

Ranges from southern Arizona, New Mexico, and Texas in the United States, throughout most of Mexico, and south into Guatemala, Honduras, and El Salvador in Central America. Populations are seasonal migrants in the northern part of the range, with year-round residency more common further south.

Altitude and depth

Typically found from sea level up to about 3000 meters elevation, with most records between 500-2000m in association with agave and cactus habitats.

Seasonal movements

Exhibits seasonal migratory behavior, moving northward into the U.S. Southwest during spring and summer to coincide with agave and cactus blooming, then retreating south to Mexico for winter. This nectar corridor migration links it closely to the flowering phenology of its food plants.

Found in arid and semi-arid habitats including desert scrub, thorn forest, oak-pine woodland, and tropical deciduous forest, often near caves, mines, or rock crevices used as roosts. It shows a strong association with columnar cacti and agave plants that provide its primary food source.

Adaptations to its environment

Possesses an elongated rostrum and a long, brush-tipped tongue capable of extending beyond the body length to reach deep into flowers. Reduced dentition and a specialized digestive system efficiently process nectar and pollen, while hovering flight capability allows precise feeding at flowers.

Listed as Near Threatened by the IUCN due to habitat loss, roost disturbance, and dependency on declining agave populations, though it remains relatively widespread across its range. Population trends are considered to be declining in parts of its range due to these pressures.

Estimated population

No precise global population estimate exists, but the species is considered uncommon to locally common with an overall declining trend attributed to habitat degradation. Regional monitoring in the U.S. suggests fluctuating but generally low numbers at the northern edge of its range.

Major threats include destruction and disturbance of roosting caves and mines, loss of agave and cactus habitat from land conversion and agave harvesting for tequila/mezcal production, and pesticide use affecting food plants. Climate change may also disrupt the timing of flowering resources critical to migration.

Diseases and parasites

Like many bat species, it can host ectoparasites such as mites and bat flies, and may be susceptible to viral pathogens including rabies, though documented cases are rare. It is not known to be significantly affected by white-nose syndrome, unlike some hibernating bat species.

Protected under various national wildlife laws in the U.S. and Mexico, with some roost sites located within protected areas or national parks. Conservation groups have promoted agave restoration and bat-friendly agave harvesting practices to support this and related nectar-feeding bat species.

Recommended actions

Priority actions include protecting and gating important roost caves/mines from disturbance, promoting sustainable wild agave harvesting practices, and preserving desert and thorn-forest habitat corridors. Continued monitoring of migratory populations and cross-border conservation collaboration between the U.S. and Mexico are also recommended.

This bat has grayish-brown to olive-brown fur, a notably elongated muzzle, and a small, leaf-like nose ornament typical of phyllostomid bats. Its tail is very short or absent, and it has large eyes relative to other bat species.

Size

Body length (head and body) ranges from about 7 to 9 cm, with a forearm length of approximately 4-4.7 cm and wingspan around 30-36 cm.

Weight

Adults typically weigh between 15 and 25 grams, with little significant difference between males and females.

Distinctive features

Distinguished from related nectar-feeding bats by its particularly long rostrum, minimal tail, and specific dental formula with reduced, peg-like teeth adapted for a liquid/pollen diet. Its long, extensible tongue with a brush-like tip is a key identifying feature.

Differences between males and females

Sexual dimorphism is minimal in this species, with males and females being similar in size and coloration.

Generally roosts in small to moderate-sized colonies, sometimes solitary or in small groups of a few individuals to several dozen. It may also roost alongside other bat species in caves and abandoned mines.

When it is active

Strictly nocturnal, emerging after dusk to forage for nectar and returning to roosts before dawn. Activity peaks are often linked to peak nectar flow times of flowering plants.

Diet

Primarily feeds on nectar and pollen from night-blooming cacti (such as saguaro and organ pipe cactus) and agave species, supplementing its diet with some fruit and insects opportunistically. It plays a crucial role as a pollinator for these plants.

How it feeds and hunts

Forages by hovering in front of flowers and inserting its long tongue to lap up nectar, using echolocation and possibly olfactory cues to locate blooming plants. It may trapline between known flowering plants along established feeding routes.

Communication

Communicates primarily through echolocation calls for navigation and possibly flower-locating, along with social vocalizations within roosts. Scent may also play a role in mother-pup recognition and mate attraction.

Interactions with other species

Serves as a key pollinator for agave and columnar cacti, forming a mutualistic relationship with these plants; in turn, the bat depends on them as a primary food source. Predators include owls, snakes, and other nocturnal predators that may take bats at roost entrances or during flight.

Role in its ecosystem

This bat plays a vital ecological role as a pollinator, particularly for agave species and columnar cacti, contributing to genetic diversity and reproduction of these plants across arid ecosystems. Its migratory nectar-feeding behavior links plant populations across a broad geographic range.

Breeding season varies by region but often occurs in late winter to spring, with females giving birth to typically a single pup after a gestation period of about 4 months. Births are timed to coincide with peak flowering resources to support lactating females.

Raising the young

Female bats care for the single pup, nursing it in the roost while foraging at night. Pups are left in roosts or maternity clusters and develop flight capability within a few weeks to a couple of months.

Maturity and lifespan

Sexual maturity is typically reached within the first year of life. Lifespan in the wild is estimated at around 10 years, though specific longevity records for this species are limited.

Classification

Mammalia > Chiroptera > Phyllostomidae > Choeronycteris > Choeronycteris mexicana

Scientific synonyms

Choeronycteris mexicana Tschudi, 1844 (no widely recognized synonyms)

Recent studies

Recent studies have focused on tracking migratory patterns using stable isotope analysis and genetic markers to understand population connectivity between U.S. and Mexican populations. Research has also examined the bat's role in agave conservation and tequila industry sustainability practices.

Compared with similar species

Similar to other long-tongued nectar bats like Leptonycteris species, but Choeronycteris mexicana has a notably longer rostrum and shorter tail. It is generally smaller than Leptonycteris nivalis and has distinct dental characteristics separating it taxonomically.

This bat's tongue can extend to nearly the length of its own body to reach deep into tubular flowers. It is one of the primary natural pollinators of wild agave plants, which are the source of tequila and mezcal. Despite migrating hundreds of kilometers, individual bats often return to the same roosts year after year.

Where and how to see it

Best observed at dusk near flowering agave or cactus plants in desert habitats of southern Arizona or northern Mexico during late spring and summer months. Visiting known roost sites in caves or mines with proper permits, or observing agave blooms at night with red-filtered lights, can increase chances of sightings.

Risks to humans

No notable risk to humans; like other bats, it should not be handled due to potential rabies transmission, but bites or aggressive behavior toward humans are extremely rare. It poses no direct threat to crops or livestock.

Human uses

This species has indirect economic importance through its pollination services to wild agave populations, which support the tequila and mezcal industries. It is also valued in conservation and educational programs highlighting the ecological importance of bats.