Davy’s Naked-backed Bat (click image to enlarge)
Copyright © Jafet M. Nassar
 
Ghost-faced Bat (click image to enlarge)
Copyright © Jafet M. Nassar
 
Curaçaoan Long-tongued Bat (click image to enlarge)
Copyright © Jafet M. Nassar
 
Miller’s Long-nosed Bat (click image to enlarge)
Copyright © Jafet M. Nassar
 
Greater Bulldog Bat (click image to enlarge)
Copyright © Ariany García-Rawlins
 
Curaçao Myotis (click image to enlarge)
Copyright © Jafet M. Nassar
 
Funnel-eared Bat (click image to enlarge)
Copyright © Jafet M. Nassar
 
Pallas' Mastiff Bat (click image to enlarge)
Copyright © Burton Lim

Five of the species living in the ABC Islands are insect-eating bats. Their entire diet consists of insects, including beetles, moths, and the annoying mosquitoes. That’s why when you sit down in the porch of your house at sunset you see fast shadows performing gracious dances around you, even entering into your house to get a snack--probably a mosquito that was going to have fun with you the entire night.

From the smallest to the largest, we have here the Curaçao Myotis (Myotis nesopolus), a dark brown bat that only weighs 3 to 5 grams. Of similar size and weight, but with yellow fur, is the Funnel-eared Bat, Natalus tumidirostris. Both of these bats fly so graciously that resemble nocturnal butterflies, quite good at avoiding obstacles. Only one individual of the Davy's Naked-backed Bat, Pteronotus davyii, has been recorded for Bonaire, but they are common in Aruba and Curacao. This little bat weighs 5 to 10 grams and its wings are attached along the mid-back, covering the dorsal fur, which gives the naked-backed appearance. They are adapted to hunt insects inside the vegetation. The next one on the list is the Pallas's Mastiff Bat, Molossus molossus, a very fast and heavier bat (10 to 14 grams), with a free tail that makes it look like a mouse with wings. It is because of bats like this one that people find a resemblance between mice and bats. Finally, we have the Ghost-faced Bat, Mormoops megalophylla, the largest insect-feeding bat on the ABC islands (15-16 grams), with a very distinctive and bizarre rostrum, mainly characterized by rounded ears like satellite antennas covering most part of its face. With the exception of the Pallas's Mastiff Bat, which lives in relatively tall buildings, roofs, mountain walls, and tall trees, the other species rely on caves to rest during the day.

The second group of bats that inhabit the ABC islands are the nectar- and fruit-feeding bats. Yes, these are bats that eat large amounts of floral nectar, pollen, and fruit pulp. They are quite different to the insect bats, because they are not as well adapted to hunt insects in the air. Instead, they have quite long tongues and small incisive teeth, or lack of them, to facilitate the protrusion of the tongue while feeding on flowers. In one sense, they behave and feed very much like hummingbirds, flying from flower to flower, and hovering in front of them when eating. The more common of the two species is the Miller’s Long-tongued Bat, Glossophaga longirostris, with brown coloration and an average weight of 15 grams. This bat is capable of living in many types of roosts, including caves, rock crevices, abandoned houses, tree holes, the roofs and attics of inhabited houses, and beneath any type of construction dark enough to allow them to rest during the day. It is a very important pollinator of the flowers of columnar cacti (kadushi, kadushi di pushi, and yatu), agaves and calabash trees. Thus, they help to produce the fruits that many animals on the island eat. Besides, this bat also feeds, to a certain extent, on insects. The other important ecological role they have is as seed dispersal agents. It's as if they are farmers, dispersing the seeds of the fruits they ingest while defecating during flight. They do not have a problem flying on open areas, where they release their precious seed loads, like bombing planes, contributing to the natural restoration of disturbed habitats on the island.

The other nectar-feeding bat is the Curaçaoan Long-nosed Bat, Leptonycteris curasoae. This is one of the largest bats on islands (approximately 26 grams) and it is more specialized on flowers and fruits than the Miller’s Long-tongued Bat. It is also a very important pollinator agent of agaves and columnar cacti, besides dispersing the seeds of the latter. But this species differs from the smaller one in several ecological and behavioral attributes. The two most important attributes are its gregarious habits and its migratory behavior. Curaçaoan Long-nosed Bats need to live in large colonies composed of hundreds, thousands, and even tens of thousands individuals. For them it is very important to have the close contact with their conspecifics, probably because that helps to keep them warm, besides facilitating social interactions they might perform. So, in order to be in large colonies, these bats need to live in caves. Concerning their migratory capabilities, it has been demonstrated that this species can fly over long distances in one night (> 100 km), including flights over the sea. Besides this, they can temporarily disappear from certain locations in Colombia and Venezuela, suggesting that at least some populations migrate. Mark and recapture of these bats on the three islands and Venezuela has demonstrated that they move between the islands, but we still do not know if the metapopulation is truly migratory or not, because we have noticed the presence of these bats on the island year round; however, their numbers tend to fluctuate throughout the year.

Finally, there are historical records indicating  other species of bats might also be living on the ABC Islands: the Greater Bulldog Bat, Noctilio leporinus, and the Little White-shouldered Bat, Ametrida centurio. The Greater Bulldog Bat would be the largest species on the island, weighing between 50 and 90 grams. Besides its peculiar bulldog-like face and yellowish fur, this species is outstanding for its feeding habit, which consists mainly of fish that they get from calm waters in lagoons and mangroves. They capture the fish with the help of their feet and long and sharp curved nails. As roosts, they use caves close to the sea and tree hollows, sometimes abandoned by the loras. The Little White-shouldered Bat was only captured once on Bonaire. This relatively rare animal of 8 to 10 grams belongs to the group of the fruit-feeding bats within the family of leaf-nosed bats, and its biology is poorly understood at present. The Jamaican Frugivorous bat, Artibeus jamaicensis, has been recorded only in Aruba and Curacao and it has a grey-brownish color, paler on its ventral side and a size of approximately 9 cm. Due to the very short distance of only 22 Km. that separate Aruba from the South American continent and the fact that this island is part of the continental shelf, 3 more species of bats have been found on this island only: the insectivore Mexican Free-tailed bat, Tadarida brasilensis, varying in color between from brown to grey, size of 9 cm and weighting approximately 15 grams; the frugivore Small Yellow'shouldered bat, Sturnina lilium and the Trinidad Dog-like bat, Peropteryx trinitaris, an aerial insectivore considered rare in all its geographic distribution. Very little is know about the ecology of these 3 species on the island of Aruba.