Volunteers for the Catlins Bat Project, run by Catriona Gower, will be conducting transects of known long-tailed bat locations in the district to provide information about populations of the critically endangered endemic species.
The transects run in parallel with a series of free bat and moth nights for the general public, the second of which will take place on Saturday night at Tawanui.
Ms Gower said additional volunteers for the project were always welcome.
"We’ve got five routes we walk each summer with bat detectors, once in January and a second time in February.
"This gives us a way to assess population numbers and compare with past years at the same sites, and allows us to get a measure on any significant trends."
The population in the Catlins appeared to be "quite good" at present.
"A recent survey at Tahakopa Valley recorded the highest number of passes in the 10 years we’ve been doing the study, so that’s very heartening."
Members of the public observing bats at other Catlins locations should get in touch.
"We’ve had reports of bats at Waikawa to the west, but no confirmed sightings yet."
Catlins Bat & Moth Night guide Annette Patterson said the events were a great way to learn more about the "special" mammal, and become enthused about conservation in the Catlins.
"I’ve been doing this for several years now, and you never get tired of people gasping and jumping up and down when they first see or hear a bat.
"We saw and heard several at our first event on December 29, and we’re expecting to see more this Saturday, and again on February 3 for our last walk of the summer."
All were welcome to take part, walking was minimal and the less mobile could bring a camp chair if they wished, she said.
Participants should meet outside the Lumberjack Bar & Cafe in Owaka about 8.50pm, and expect to be finished by 10pm.
Bookings were preferred, by calling her on 027415-8168.
