Aye-aye

Tolkien: Male, born on January 7, 2001 at the Duke Lemur Center in Durham, NC. Arrived Philadelphia Zoo, July 1, 2009.
 
Medusa: Female, born on October 14, 2003 at the Duke Lemur Center in Durham, NC. Arrived Philadelphia Zoo, July 1, 2009.
 
Smeagol: Male, born on July 14, 2010 to Medusa and Tolkien at the Philadelphia Zoo.

Loki: Male, born on July 5, 2012 to Medusa and Tolkien at the Philadelphia Zoo.

Where to find me in the Zoo

PECO Primate Reserve

Fun Facts

• Aye-ayes are nocturnal, so they are most active at night.
• Due to its specialized body type, behavior, and uniqueness among primates, the aye-aye is included in its own family, genus and species.
• They have ever-growing incisors and an elongated, flexible middle finger on each of its hands.

Ask an Expert

Aye-ayes are dark in color and have large, black, moveable ears. There is little to no sexual dimorphism (size difference between the sexes) in the aye-aye. They are nocturnal, solitary foragers with a large brain-to-body ratio. Aye-ayes have two layers of hair and a large, bushy tail. They have ever-growing incisors and an elongated, flexible middle finger on each of its hands, which moves independently from the other digits. There are only a handful of facilities that have captive aye-ayes in both Europe and the United States. The only U.S. facilities that house aye-ayes are; the Duke Lemur Center (Durham, NC), Denver Zoo, San Francisco Zoo, Omaha Zoo and the Philadelphia Zoo.

Longevity

A typical lifespan for aye-ayes in zoos is 20-25 years. Typical lifespan in the wild is not known, but is likely to be shorter than in zoos.

Reproduction

They reach sexual maturity at 2 years of age. Pairs will mate any time of the year and give birth every 2-3 years. The gestation period is 160-170 days and the young nurse up to one year. Aye-aye females typically "park" their infants in the nest for a majority of the first two months of life.

Behavior

Aye-ayes spend 70-80% of the night feeding and traveling. The aye-aye's elongated third digit is used to to assist them in percussive foraging. Percussive foraging is a specialized foraging technique that involves tapping on branches or rotting wood that may contain insect larvae (similar to a woodpecker), which they extract with their long fingers. Aye-ayes use their large, mobile ears to assist in locating larvae in wood, which they gnaw open using their ever-growing incisors.

Size

Adult aye-ayes measure 14-17 in (36-43 cm) head-to-tail. The long tail is approximately 22-24 in (56-61 cm).

Weight

Adult aye-ayes weigh 4-6 lbs (181-272 kg).

Diet

The aye-aye is omnivorous, feeding on a variety of foods in the wild including insects, nectar, seeds, fruits, nuts and fungi. At the Zoo, aye-ayes are offered a base diet of aye-aye gruel consisting of primate biscuit and water with a different ingredient added each day for flavor. The enrichment portion includes a variety of fruits, vegetables, insects, eggs, and nuts. The diet is offered over the course of the day to simulate normal feeding patterns of wild aye-aye. Insects are offered live and must hunted for and captured. This results in activity that provides exercise and nourishment.

Geographic Range

Madagascar (primarily east cost rainforests, also dry forests in northwest and west of the island).