Frequent visitors to this blog will know my longstanding fascination with the mammals of Australia. Because of its long geographic isolation, the island continent was mostly free of eutherian (placental) mammals until very recently–meaning that magnificent non-placental oddballs such as platypuses, wombats, echidnas, quolls, and numbats had plenty of time and space to survive and flourish. However there is one order of placental mammals which proved to be a big exception to this general narrative. Bats are eutherian mammals which can fly. They reached Australia in the Oligocene (the Oligocene era lagerstätten at Riversleigh have yielded 35 species of microchiropterans) and have been very successful ever since.
Australia has 65 known species of bats, most of which are still fast tiny insect eating microchiropterans. In recent times though a few species of large fruit-eating megabats have showed up and made inroads into the continent. One of these megabats is the subject of this post–the spectacled flying fox (Pteropus conspicillatus), a big handsome bat which is widespread along the coasts of New Guinea and seems to have established a beachhead in Northern Queensland.
Spectacled flying foxes are gregarious social animals which live in huge colonies high in the canopies of the rainforest. At night they feed on nectar and pollen from tropical blossoms or they squeeze the juice from fruits like mangoes and figs. Although large for bats, the animals weigh less than a kilogram (2.2 pounds) and their wingspan is about 1.2 meters (4 feet). They are called spectacled bats because of the strips of yellow-tan fur around their eyes.
It is unclear when the bats came to Australia but the fact that they are indigenous to many of the islands around New Guinea indicates that they are powerful fliers. Additionally, like certain other fruit bats, the spectacled flying fox can occasionally sip sea water without any ill effects.
Even though they are hunted as bush meat in parts of New Guinea, Spectacled flying foxes are doing fairly well in that part of their range. Unfortunately in Australia they are having trouble with deforestation and with the paralysis tick (one of the many horrifying toxic pests which abound in Australia). Kindly and good-natured Australians frequently rescue orphaned bats, and, when not reintroduced into the wild the captive bats can live over 17 years in captivity. The bats are social animals, so the lonely orphans often bond deeply with their human rescuers.