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Bats: Bats are the only mammals that fly. Their wings consist of skin membranes which are braced internally by very elongated hands and fingers. Nocturnal, most bats use sight and echolocation to navigate and find prey. Typically, bats are social and roost in groups. Different species feed on a great variety of foods: in Iwokrama, some species eat fruits, others pollen and nectar, insects, or small vertebrates (including the fishing bat), and there are even two species of vampires that feed on blood.
River Bat
Rhynchonycteris naso River Bat image
Size: body=4 cm; weight=5 g
Description: Tiny; fur grizzled greyish, with two inconspicuous, wavy whitish stripes down back, and distinctive tufts of pale fur along forearm; nose long, projects beyond lower jaw.
Activity: Nocturnal (crepuscular), aerial. Becomes active earlier than most bats and can sometimes be seen foraging for insects in the dimming light of late afternoon or early morning.
Habits: This well camouflaged bat roosts in small groups lined up close together on the underside of logs or tree trunks leaning over the water. It usually flutters away like a swift butterfly when approached too closely.
Habitat: Forest edge, along rivers and lagoons. They can be easily seen by traveling down-river in boat or canoe, wherein groups occur every kilometre or so.
Status: Often common.
Distribution in Iwokrama
Greater White-lined Sac-winged Bat
Saccopteryx bilineata Greater White-lined Sac-winged Bat image
Size: body=5 cm; weight=7 g
Description: Medium-sized blackish bat with two wavy white lines on the back. Wing sacs, prominent in males, in front of forearms near elbow.
Activity: Nocturnal. Begins to fly at dusk.
Habits: Forages near the roost at dusk then further away as the evening progresses. Roosts together in groups of up to 50 in tree hollows or cavities of large buttress trees. Several harems of one male defending up to 9 females can be found roosting together.
Habitat: Primary and secondary lowland rainforest.
Status: Common. The bat most likely to be encountered when walking trails and searching for roosts.
Distribution in Iwokrama
Chestnut Sac-winged Bat
Cormura brevirostris Chestnut Sac-winged Bat image
Size: body=5 cm; weight=9 g
Description: Medium-sized chestnut brown with glandular sacs extending to the edge of wing in front of elbows. Wing membrane attaches near base of toe.
Activity: Nocturnal. Begins to forage in the early evening.
Habits: Feeds on small insects. Roosts in large rotting logs and in tree hollows in small groups. Roosting individuals may stack up on top of each other.
Habitat: Lowland rainforest. Open spaces near the edge of forest or over water. Often seen fluttering over the road through Iwokrama Forest.
Status: Locally common. In Iwokrama this is the most commonly encountered bat roosting in large fallen logs.
Distribution in Iwokrama
Northern Ghost Bat
Diclidurus albus Northern Ghost Bat image
Size: body=7.5 cm; weight=20 g
Description: Large, white bat with translucent pinkish wings. Glandular sac near tip of tail in centre of large tail membrane. This is the largest of four species of ghost bats in Iwokrama.
Activity: Nocturnal.
Habits: Flies high in open areas over rivers, foraging for moths and other insects. Roosts in small groups (up to 4) under palm fronds.
Habitat: Forested areas usually over open bodies of water, but also found in towns and clearings.
Status: Rare.
Distribution in Iwokrama

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