Aye-Aye: Daubentoniidae

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AYE-AYE: Daubentoniidae

PHYSICAL CHARACTERISTICS

An aye-aye (EYE-eye) has long, woolly, black or dark brown hair tipped with white. Its head is rounded with a short face. Large, hairless black ears are 4 inches (10 centimeters) long and 2.8 inches (7 centimeters) wide. Large eyes are golden brown. The aye-aye has white around its nose and above its eyes. Front teeth, or incisors, are quite large. The incisors grow continuously, and keep growing back as they are worn down by the aye-aye gnawing on trees.

The aye-aye is about 16 inches (40 centimeters) long, including head and body. It has a bushy tail, which, at 22 inches (55 centimeters), is longer than its body. An aye-eye weighs about 6 pounds (2.7 kilograms). Males and females are about the same size.

An aye-aye's arms and legs are about the same size, enabling it to move easily on all fours. Especially unique, or different, are the aye-aye's forefeet or hands. Its hands have five long thin fingers, with an extremely long thin bony middle finger. There is a pointed, clawlike nail on every finger and toe, except for the big toes, which have flat nails. The aye-aye uses its hands for feeding or cleaning itself.

Another unusual feature is the aye-aye's two nipples, for nursing or breastfeeding, which are placed on the lower abdomen rather than on the chest. Aye-ayes are the only primates with this body arrangement.

GEOGRAPHIC RANGE

Aye-ayes are found in Madagascar.

HABITAT

Aye-ayes live in several habitats, including rainforests where the weather is damp or wet throughout the year, dry forests that get little rain, mangroves or riverbank tree areas, and bamboo thickets or groups.

DIET

An aye-aye's diet consists of fruits, fungi, seeds including coconuts, nectar (sweet liquid) from palm tree flowers, and wood-boring beetle larvae (LAR-vee) or young. To get at the soft larvae feeding within trees, the aye-aye walks along tree branches, its nose pressed against the bark. The aye-aye has excellent hearing. It may tap on a branch, listening for hollow spaces created by larval feeding. When a larva is located, the aye-aye gnaws quickly through the wood with its long incisors, or front teeth. Larvae are squashed with the aye-aye's unique long, thin middle finger. Squashed remains are scooped out, bit-by-bit, and licked off the tip of this middle finger. Larvae add protein and fat to the aye-aye's diet.

The aye-aye also uses its strong incisors to tear through the outer surface of hard-shelled nuts. Unripe coconuts are a favorite. The aye-aye chews on them until it makes a hole. Then, it uses its long middle finger to scrape out the thick coconut milk and the softer interior, eating both.

NOSY MANGABE SPECIAL RESERVE

Aye-ayes were once thought to be extinct in Madagascar. But in 1957, a small group was discovered living on Madagascar's east coast. There were many attempts to protect its habitat there, but the aye-aye population kept growing smaller. Finally, to prevent the aye-ayes total disappearance from the world, two French scientists spent weeks collecting nine protesting aye-ayes. They were released on a nearby uninhabited island called Nosy Mangabe. This island is just 2 square miles (5.2 square kilometers) in size. However it is covered in dense rainforest with many very tall trees. Scientists hoped the aye-ayes would survive there. For many years, scientists weren't sure. Aye-ayes move about only at night, and vegetation is thick, so they are hard to find. However, eventually some nests and aye-ayes were seen. It is hoped that aye-ayes will multiply on this protected island.

BEHAVIOR AND REPRODUCTION

Aye-ayes are nocturnal, or active at night. Each spends most of the day in an individual nest hidden among thick vines that are within a high fork of a tall tree. Each round nest, about 20 inches (50 centimeters) wide, is constructed of leaves and twigs woven together. Each nest takes about twenty-four hours to build. It has a closed top, a side entrance, and a bottom layer of shredded leaves. An aye-aye may build up to twenty nests in its home range. Aye-ayes often change their daytime sleeping nest. Many different aye-ayes may individually occupy a nest over a period of time.

Each aye-aye usually lives alone, however young may stay with the mother for quite a while. Little is known about their social behavior. Female home ranges, or feeding areas, are not usually shared. Male home ranges are larger, and may overlap female home ranges. Range boundaries are marked with urine and with a special scent gland. Some scientists believe that aye-ayes may search for food in male-female or male-male pairs.

When moving upward, the aye-aye climbs with a series of rapid leaps, one after another. It also walks on four limbs on the ground, but more slowly.

A female aye-aye is ready to mate at three to four years old. Mating can occur during several months of the year. Several males fight over who will be the one to mate with a female. However, after this mating, the female may mate again with a different male. Pregnancy is about five months. Females only give birth every two to three years. Births can occur at any time of the year. There is only one infant each time. Babies are weaned, or stop nursing, at about seven months old.

When moving about in the trees, aye-ayes are usually quiet. But they can make many different vocalizations, or sounds. These include an "eep" call when meeting another aye-aye, a "hai-hai" alarm call when fighting over food, and a begging "bird call" given by young aye-ayes that want to feed with older animals.

AYE-AYES AND PEOPLE

In many unprotected areas, aye-ayes are destroyed by the local people, either due to superstition, or because of aye-aye crop raiding on coconut plantations—large coconut growing areas. This problem began when their normal feeding areas were destroyed.

CONSERVATION STATUS

Aye-ayes are considered Endangered, facing a very high risk of extinction, or dying out, due to superstition-related killing, loss of habitat due to logging, and use of former tree land for crop growing. At one time they were considered to be extinct, however some were later found and moved to safer sites. Currently there are aye-ayes in about sixteen reserves, or semi-protected areas, and some other places.