There are three species of bats in New Zealand: the long-tailed bat, the lesser short-tailed bat, and greater short-tailed bat. The greater short-tailed bat is thought to be extinct.
The long-tailed bat found in our project area (Chalinolobus tuberculatus) belongs to a more widespread family and is closely related to five other species of wattled or lobe-lipped bats in Australia and elsewhere. Long-tailed bats are smaller than the short-tailed bat, chestnut brown in colour, have small ears and weigh 8-11 grams.
The bat’s rely on echo-location to navigate and find food. They bounce high frequency sounds off their surroundings to identify food and other objects while flying. They can fly at 60 kilometres per hour, can fly long distances and they have a very large home range (100 km2).
They rest by day and feed by night and are less active in winter; they can even enter a torpid (semi-hibernation) state during colder months. They are social animals, with sometimes 10 to 50 bats roosting and feeding together. They hang upside down and hold onto the roost with claws of one or both feet
Maori folklore refer to bats as pekapeka and associate them with the mythical, night-flying bird, hokioi, which foretells death or disaster.
In the past, bats used large, old canopy trees (rimu, kahikatea, totara, pukatea) to roost in, either beneath the bark or in cavities. With the clearing of native forest and subsequent loss of natural habitat, bats have had to find other roosts in old exotic trees. They also roost in dead trees and frequently move between different roosts.
An aerial insectivore, it feeds on small moths, midges, mosquitoes and beetles.
Long tailed bats may separate into male and female colonies during breeding season. The breeding females give birth to one pup per year. They carry juveniles during feeding flights until adolescence at around 4-6 weeks.
The long-tailed bat is listed as ‘critical/vulnerable’. They are in danger of extinction in the medium term if nothing is done to reverse their population declines. These species are a high priority for conservation.
Causes of decline are combinations of:
- Clearance and logging of lowland forests
- Cutting of old-age trees for fire wood
- Predation by introduced animals such as cats, possums, rats, and stoats
- Exclusion of bats from roosts by introduced mammals, birds, wasps, and human interference.
New Zealand’s bats are rapidly heading towards extinction caused by rat plagues.