Sixty threatened long-tailed bats in Fiordland will be tracked every 30 seconds this summer as researchers use tiny GPS transmitters to uncover their secret movements.
Bats Beyond Borders is the Department of Conservation-led research programme that aims to collect highly detailed information about where long-tailed bats travel, forage and roost.
The bats, weighing up to 12g each, will carry transmitters weighing just 1g – the weight of a raisin.
These connect to a network of 20 base stations set up across the Eglinton Valley in Fiordland.
Researchers will receive each bat’s location every 30 seconds for about 12 days, depending on the tiny rechargeable battery life.
Established in 2025, the three-year programme, supported by Air New Zealand, successfully piloted the new tracking system on seven bats last summer.
Department of Conservation project lead Dr Emma Williams said the breakthrough technology was an exciting step for conservation.
Long-tailed bats have the highest threat ranking, Nationally Critical.
They live throughout mainland Aotearoa and its smaller islands, can travel up to 40km every night and can even lift up to 80 to 100% of their body weight.
Both long-tailed and short-tailed bat numbers are increasing in the Eglinton Valley thanks to long-term predator control to suppress rats and stoats.
Williams said it was the first time GPS trackers had been made small enough to attach to bats and reveal their fine-scale movements.
“Up until now we’ve only been able to attach VHF trackers, which require us to physically follow and locate bats to understand where they go and what resources they need.”
She said this method was problematic, with bats commonly outpacing researchers because they fly faster than a vehicle.
“This technology gives us a window into the secret lives of bats,” Williams said.
“These remarkable nocturnal mammals spend most of their lives out of sight, but we’re now able to see in very high detail where they go, how they behave and what they need to thrive – all while the rest of us are sleeping.”
Williams said Bats Beyond Borders was a “true team effort”, involving Air New Zealand funding, specialist installation expertise from Global Messenger and local landowners hosting base stations.
“This research reflects the true spirit of naturing: giving back to the environment through meaningful action.
“We can use this information to better target predator control and habitat protection for bats.”