Rare bats remain elusive but owls find new homes

A student who spent the summer searching Banks Peninsula for a rare bat has instead uncovered more native owls.

A morepork owl shelters in a roost box.

Lincoln University summer scholar Karina Hadden was tasked for 10 weeks with searching for the long-tailed bat, Chalinobus tuberculatus, which is about the size of a mouse, but found no sign of the elusive creatures.

“Not finding bats doesn’t necessarily mean they’re not there, but if present, they would most likely be in small numbers. There’s probably not a sustainable population or chances are, we would have found some,” Karina says.

The long-tailed bat was last recorded on Banks Peninsula in 1963 and a 1990s survey failed to locate any of the tiny animals.

However, the isolated geography of the area makes the species a good candidate for a remnant population and some recent unconfirmed sightings by members of the public prompted this new search.

Karina’s project, funded by the Christchurch City Council and supported by the Department of Conservation and the Banks Peninsula Conservation Trust (BPCT), involved Karina placing 50 acoustic recorders in various bat-friendly areas and later analysing the results.

The recorders were programmed to detect “bat-like” calls, which would be verified by bat specialists.

Karina also helped Banks Peninsula Conservation Trust with a separate project to determine the distribution of native morepork in the area. She placed different monitors out during the bat survey to try and detect the small owl.

“Bats were the main focus of the project, but we did find morepork in at least one new location,” she says.

Although the native owls are widespread in many parts of New Zealand, they are not as common on Banks Peninsula.

The BPCT is also working to boost morepork habitat in the area and recently about 75 roost boxes have been installed with help from volunteers, including the Akaroa Men’s Shed. A morepork named Wol has already set up camp in an Okuti Valley Reserve roost box.

An introduced species, little owl, also use the roosts.

Karina says nature could be given a helping hand on Banks Peninsula by protecting cabbage trees, willows, and other large trees, which form holes suitable for bat roosting, as well as for morepork.

In spite of a fruitless search for the long-tailed bats this time around, Karina says that since the recovery of old forest growth takes decades, another bat survey should be carried out in 10 to 20 years’ time.

If you think you may have sighted a long-tailed bat on Banks Peninsula, contact Department of Conservation Technical Advisor Moira Pryde at mpryde@doc.govt.nz. Include the date of the sighting, time of day and GPS location.

If you would like to build and install a morepork roost, email Alison Evans at okuti@ihug.co.nz.