Media & Education
Volume 35, Issue 2, 2016
Rodrigues Fruit Bat
Local and International Partners Work Together to Save the ‘Golden Bat’
Often called the “golden bat” by locals for the thick, burnished fur encircling its neck, the Rodrigues Island fruit bat is found only on a 41-square-mile volcanic ridge in the middle of the Indian Ocean, nearly 1,000 miles from Madagascar. With its short pointed snout, bright round eyes and small triangular ears, this medium-sized bat looks like a schipperke dog (with wings!). Though they are not strong flyers, their powerful jaws are more than capable of pulverizing a wide variety of fruits and leaves, including introduced tamarind, mango, fig, as well as native palm fruits.
The bats require tall, mature trees in large, contiguous tracts of forest for roosting and breeding. These forests also provide protection from frequent cyclones, which can easily blow down smaller stands of trees and sweep bats out to sea. A highly social species, Rodrigues fruit bats congregate together in large roosting groups, though when they depart in the evening to feed, their behavior is more solitary. At the roost, breeding males monitor harems of eight to 10 females, while non-breeding males roost elsewhere. Like most bats, Rodrigues fruit bats reproduce slowly, with females bearing only one pup per year.
This species is also known for their remarkably strong musky odor, which they rub on tree branches and foliage, as well as on other bats, a tactic thought to aid in social identification among the colony.
As one of the last remaining endemic vertebrates on Rodrigues, fruit bats, like other flying foxes, are thought to be important dispersers of seed and pollinating agents on the island. As “strong interactors” with their ecosystems, should the Rodrigues fruit bat be eliminated from the island, the few remaining native plant species left on Rodrigues, which rely on the bat for pollination or seed dispersal, may also slide into extinction.
After the close of World War II, Rodrigues Island was heavily deforested for farming, eliminating much of the bats’ natural habitat. From an estimated population of 1,000 in 1955, only 70 to 100 bats remained by 1979. Though they number around 20,000 today, Rodrigues fruit bats are still critically endangered due to their extremely limited geographic range. In the Cascade Pigeon River Valley and other spots around better-forested areas of the island, individual fruit bat roosts can number in the thousands, and bat groups follow seasonally fruiting and flowering trees as they come into season.
Habitat loss remains a strong threat to the continued success of the Rodrigues fruit bat’s future. However, aggressive reforestation and a long-term environmental education program by the Rodrigues Environmental Education Program (REEP) have helped rebuild bat numbers. Supported by the Philadelphia Zoo and the Mauritius Wildlife Foundation, REEP not only educates residents, landholders and students on the importance of forest restoration and biodiversity, but also runs a plant nursery to raise native species to donate for planting. Talks, volunteer days, bat counts and classes involve the community in the revitalization of the island’s habitats.
This species also holds distinction as the only bat managed under an American Association of Zoos and Aquariums Species Survival Plan (SSP) to be successfully bred in captivity. In 1976, the Jersey Preservation Trust, now the Durrell Wildlife Conservation Trust, took 25 wild Rodrigues fruit bats into captivity to begin a captive breeding program on the Channel Island of Jersey, England, as a safeguard against possible extinction. After initial success, the Trust established a second breeding program on Mauritius, which remained as the only other captive breeding program in the world until the 1990s, when zoos, including the Philadelphia Zoo, were able to bring breeding pairs to the United States to expand captive breeding efforts and safeguard the future of Rodrigues fruit bats.
Today, 16 zoos host 180 Rodrigues fruit bats in captivity across the United States, including Philadelphia Zoo’s 35 individuals.
Currently, there are no plans to reintroduce any of the Rodrigues fruit bats now in zoo-based captivity, in large part because the island’s fragmented forest habitat seems to be supporting as many bats as it can at the moment. By working with groups like REEP, the residents of the island of Rodrigues have demonstrated that saving their charismatic fruit bat is a goal worth pursuing