THREATS TO BATS
Imagine yourself at home, snuggled in bed, fast asleepwhen a group of tourists enters your house and shines a light in your face. If your house is popular enough to be visited nightly by the tour guide, you'd probably decide to move to a new home afterall, you need your sleep to function on your daytime job. But what if there was no place else to live?
HUMAN DISTURBANCE: Millions of bats worldwide are killed by people who explore caves. Although some people intentionally kill bats, most are unaware of the harm they can cause. In temperate regions, where bats hibernate during winter, human entry causes bats to arouse and waste 10 to 30 days of stored fat reserves. Consequently, they may not have enough energy in reserve to survive until spring, when food becomes available. When not hibernating, bats stay on the "edge of starvation" to maintain their flight efficiency. Flight is energetically expensive and repeated or prolonged flights caused by disturbance can lead to exhaustion and death. During -the breeding season, which in the tropics may be year-round, flightless young may be dropped or abandoned when nursery roosts are disturbed.
HABITAT LOSS: The roosting cave is only one, albeit critical, component of the environment used by bats. Deforestation results in a direct reduction of food for frugivores and nectarivores. Insectivores may experience a collapse of their prey base. Some bat species prefer to feed under a closed-canopy, avoiding open spaces where they, themselves, are vulnerable to nocturnal predators. Forest regeneration may be hindered as bats choose not to fly across open, patchy habitats. As a point of concern, Jamaica, which is only 11,000 km2, has the world's highest rate of deforestation according to the World Resources Institute 1998-99.
PROTECTION OF JAMAICA'S BATS
Windsor Great Cave is managed by the Jamaica Conservation & Development Trust (JCDT). Visitors must by accompanied by a warden into the cave. We kindly request that all guests sign the visitor registry so we may better monitor numbers and trends. JCDT is working with biologists at the Windsor Research Centre to study the natural history and demography of the bats to ensure optimal management for the long-term conservation of the bats and their cave environment.
All bats on Jamaica are protected by the Wildlife Protection Act, administered by the Natural Resources Conservation Authority (NRCA). If you see someone harming or killing wildlife, please report to:
(In Windsor) - Windsor Research
For more information about bats, visit
the website of Bat Conservation International, Inc.
This pamphlet was prepared by the Windsor Research Centre with the support of Bat Conservation International
WINDSOR RESEARCH CENTRE
Bats emerging at dusk from Windsor Great Cave
Ratbat, 'im always leave deh ripe
Jamaica is home to a rich diversity of bats. Although known locally as 'Ratbats,' bats actually are more closely related to primates than they are to rodents. Their scientific classification, Chiroptera, comes from the Greek roots cheir (hand) and pteron (wing). As the name implies, the wing of a bat is a highly modified hand, with elongated fingers and forearm over which a thin, elastic skin is stretched.
Twenty one species occur across Jamaica and four of these are endemic, found here and nowhere else in the world. Of the 21 species, 15 depend on caves for daytime roosting and breeding nurseries. The qualities that make a cave "good" for bats are not well-known on Jamaica. Indeed, of more than 1200 caves and small chambers mapped throughout the island, less than 20% are occupied by bats.
WINDSOR GREAT CAVE
Located on the northern edge of the rugged karst limestone Cockpit Country, Windsor Great Cave has long been recognized for its extraordinary bat diversity. At least 8 species, representing 3 foraging guilds are resident:
Parnell's Moustached Bat Pteronotus parnellii, Leaf-chinned Bat Mormoops blainvillii, Big-ear Bat Macrotus waterhousii, & Free-tailed Bat Tadarida brasiliensis feed mostly on insects
Jamaican Fruit Bat Artibeus jamaicensis feeds on fruits & seeds
Long-tongued bats Glossophaga soricina & Monophyllus redmani, & Brown Flower Bat Erophylla sezekorni feed on pollen, nectar, fruits & insects
Two additional species of Moustached Bats, Pteronotus f. fuliginosus and Pteronotus macleayi griseus, were considered 'common' up to the early 1970s but neither has been seen in over 25 years. The causes of their decline and disappearance remain a mystery.
The number of bats in Windsor Great Cave is estimated 50,000-100,000. The bats roost in two large chambers, with segregation maintained by species.
WHY ARE BATS IMPORTANT?
In addition to their intrinsic value as unique animals, bats serve key functions in maintaining healthy ecosystems:
POLLINATORS: Bats pollinate numerous plants, including economically important crops such as banana, mango, and avocado ('pear')
SEED DISPERSERS: In the tropics, bats are responsible for 70-95% of all seeds dispersed, thus ensuring forest regeneration
INSECT CONSUMPTION: Insectivorous bats eat enormous quantities of insects, including those that are harmful to crops and pests to humans. For example, a 13-gram Parnell's Moustached Bat could easily consume > 1000 insects, including mosquitoes, per night. If 50,000 individuals are present in Windsor Great Cave, that's at least 18,250,000,000 insects per year!
A WORLD OF DARKNESS?
Contrary to common myth, bats are not blind. Many species, notably frugivores and nectarivores, rely on vision (and olfaction) for locating food. Have you noticed that many flowers which open at night are white?
Bats, however, are most well-known for their ability to echolocate. This involves sonar --emitting brief, usually ultrasonic sounds through the mouth or nose and receiving the echo to "see" with sound. Some tropical bats have overcome the problem of distinguishing insects from raindrops by using Doppler Shift (changes in frequency as the bat moves relative to its target; for humans, the sound of a train whistle changing pitch as it speeds past) to measure flight speed and wing motion of insects.