Proboscis BatRhynchonycteris nasoWhere and when to see them

The proboscis bat is a tiny insect-eating bat found in tropical lowland regions from southern Mexico through Central America into South America, including the Amazon Basin. It belongs to the sac-winged bat family, Emballonuridae. Its common name refers to its elongated, pointed snout. Unlike bats that hide deep inside caves, it often rests in plain sight on shaded surfaces beside water. Its mottled coat helps it blend into bark and weathered wood.

Size

Approximately 3.5–4.5 cm in head-and-body length.

Weight

Approximately 4–6 g.

Lifespan

Lifespan in the wild is not well documented.

Status

Least Concern (IUCN).

Proboscis bats are social and usually spend the day in small groups. They cling to tree trunks, branches, roots, or other surfaces over or close to water. Roosting individuals often arrange themselves in a line, with space between neighboring bats. When disturbed, members of a group may rock their bodies together, a movement thought to help them resemble vegetation moving in the breeze. They generally begin foraging around dusk and hunt close to the water's surface. Echolocation helps them locate flying insects and navigate in low light. Suitable daytime roosts may be used repeatedly, making quiet, undisturbed waterside sites particularly valuable.

• It is the only living species in the genus Rhynchonycteris.
• Its elongated snout gives it the name proboscis bat.
• Roosting groups may rock their bodies in unison.
• Its patterned fur camouflages it against bark.

Wildlife opportunities depend on the river reach, water levels and species. River-specific viewing months have not been confirmed; general species seasons are not a local sighting forecast.

This species is closely associated with rivers, streams, lakes, and other freshwater habitats in tropical lowlands. In the Amazon Basin, it occurs along forested waterways and sheltered waterside margins. Daytime roosts typically provide shade and an exposed surface from which the bats can drop into flight. They may also use bridges and other human-made structures near water. Nearby vegetation and productive aquatic habitats provide both shelter and feeding opportunities.

Proboscis bats feed on small flying insects. Small flies, including insects associated with freshwater habitats, are important prey. They capture prey in flight, often while patrolling low over water. They do not feed on fruit, nectar, or blood.

Common name

Proboscis Bat

Scientific name

Rhynchonycteris naso

Animal group

Mammals

Size

Approximately 3.5–4.5 cm in head-and-body length.

Weight

Approximately 4–6 g.

Lifespan

Lifespan in the wild is not well documented.

Status

Least Concern (IUCN).

Identification

Look for a very small bat with an elongated, projecting snout and grayish-brown, mottled fur. Two pale, often wavy stripes run lengthwise down the back. Small pale tufts along the forearms are another useful feature when visible. Its habit of roosting in spaced lines on waterside wood is a helpful clue, but identification should also rely on physical features.