One of New Zealand’s rare bats is on its way to recovery, having its population in Fiordland's Eglinton valley grow from 300 to 3000 in over a decade.
Southern short-tailed bats have moved their status from "threatened" to "recovering" in an updated report on New Zealand Threat Classification System for New Zealand bats.
Minister of Conservation Eugenie Sage released the new report today, saying the status change for these bats was largely due to DOC’s sustained control of rats, possums and stoats in its last mainland habitat for more than a decade.
The Eglinton is the last known place in the South Island for this bat subspecies. According to DOC the population of long-tailed bats in the same area is also growing at a similar rate.
However the picture was not as good for bats in other areas, particularly the North Island, Ms Sage said.
“The status of our North Island long-tailed bats has worsened since 2012 and they are now grouped with their South Island counterparts in the highest threat category of ‘nationally critical’.”
DOC says the new threat assessment confirms that bats can recover where their forest habitat is safe and predators are suppressed.
“Yet in many areas populations of both bat species continue to decline due to the threat of rats, stoats, possums and cats, and clearance of lowland forest and large old trees where bats roost,” Ms Sage said.
The effects of wasps and potential effect of kauri dieback on roost trees was also of concern.
New Zealand has two species of bats—the long-tailed bat and short-tailed bat, of which there are three subspecies. A third species—the greater short-tailed bat—is thought to be extinct.
The threat status of the central and northern short-tailed bat subspecies, found in the central and northern North Island, remains the same as in 2012. That is, both are declining.
Bats can fly up to 30 kilometres from their roosting areas to forage and a colony range over more than 100 square kilometres. DOC says this can make them seem more numerous than they actually are.
DOC administers the New Zealand Threat Classification System, which draws on expertise from the wider science and conservation community.
Conservation status of New Zealand bats, 2017: http://www.doc.govt.nz/nature/native-animals/bats-pekapeka/