Bats Essay Research Paper BatsINTRODUCTIONThere are an — страница 2

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usually move from the south to far north during the summer and they return during the fall. Bats that hibernate prepare for the winter by getting fat in autumn. Then they fall into a sleep more extreme than their normal daily sleep. As in most animals, when hibernating their major bodily functions, such as heart-rate and breathing, are suppressed greatly. Bats are known to interrupt their hibernation because they have been seen in the winter. Disturbing bats during hibernation can be very destructive (Pistorius 94). This is because the bats have a limited supply of energy. The energy used when the bat is awake is huge compared to that when it is hibernating. Bats arise on occasion anyway to groom, or sometimes take a flight outside, and even to move to colder places, where they

can survive with lower metabolism and save energy. Repeated awakenings can result in starvation in the late winter from lack of energy stores. In an extreme case in Kentucky, during the 1960?s where a cave was a tourist attraction ,the population of 100,000 bats starved to death after being awakened so many times. REPRODUCTION Bats have internal fertilization and give birth to highly matured young like humans (Lauber, Honders 75, Ezzel 92). Most bats only have one baby a year. The bats mate in the roost and have little or no courtship. The pregnant mothers form separate nursing colonies from the others. Some species like the Mexican free-tailed bat, who migrate immediately after mating, produce a secretion that preserves the male?s sperm until they reach their new roost. When

their baby is being born the mother hangs by her thumbs to a tree branch. Its tail membrane acts as a cradle and the baby is born into it tail first. Then the mother hangs by one wing and cleans the baby with the other. IT is then attached to the mother?s teat where it will hold on during flight. In some species the baby is left at the roost when the mother is hunting, in others the baby is taken along. In the species that carry their young eventually the baby grows to big for the mother and is left in the roost. The bat then learns to fly and hunt its prey by itself (Lauber). SPECIALIZED BATS Some bats have developed special ways of adapting to their surroundings. Though most bats eat insects some feed on fruit, nectar, small vertebrates, fish, and blood (Bourliere 95). The bats

that eat fruit help disperse seeds by eating fruit and then dropping the seeds in their droppings during flight. Those that drink nectar act like hummingbirds pollinating flowers (Warning from Bat Conservation International 91). Bats that eat small vertebrates along with insects and fruit are often called false vampires. These bats eat lizards, tree frogs, birds, rodents, and smaller bats. They kill their prey by using thier strong jaws and teeth to break their neck. These bats have only about a two foot wingspan so thier prey tends to be small. Bats that catch fish fly just above the water and catch the fish with its hind feet and use its sharp claws to hold it. It then maneuvers the fish to kill it by biting it (Novick 73). The most famous of bats is probably the vampire. The

vampire bat drinks the blood of large vertebrates, to do this they have developed large incisors, a specialized tongue, and specialized saliva to prevent blood from clotting, and they are able to move quickly on the ground in the case of its prey waking up and it is too full to fly away (Honders 75).