Solar bat monitors uncover secrets of Auckland's night sky

NZ Herald

06-07-2025

They don't screech or suck blood. But they do sing. Tiny and elusive, New Zealand's long-tailed bat is the country's only native land mammal, and it's critically endangered.
'Bats get a bad rap,' said Neil Henderson, a conservationist with Kaipātiki Project. 'People lump them in with pests like rats, but they're actually one of our most extraordinary native species.'
He should know. Henderson used to frequently drive more than 100km just to check a battery in a bat recorder. That's changed thanks to solar power and support from Meridian's Community Decarbonisation Fund, an initiative helping local organisations cut emissions.
'We'd go all that way just to check a card or swap out batteries,' he said. 'Now with solar, I've had monitors out for four months straight. I just pop by, switch the card and leave them running.'
The fund has helped Kaipātiki Project set up 10 solar-powered audio bat recorders across northwest Auckland, including sites in Riverhead, Paremoremo and the Upper Harbour area. The result is less travel, no single use batteries, and richer, longer-term data with a much smaller carbon footprint.
'We're a lean, resourceful NGO fueled by passion and purpose,' Henderson said. 'Saving time, petrol and batteries is huge for us.'
Since 2022, Meridian's fund has invested nearly $3 million in community projects like this – from solar panels to EVs to creative, low-emission tech that supports biodiversity. But the Kaipātiki Project was an unusual one, Henderson said. 'They're used to putting solar on sheds. But I think they liked the novelty of it.'
Despite rapid urban development, long-tailed bats or pekapeka are still gliding through pine forests, farm gullies and stream corridors. Some fly at speeds of 60km/h, covering several kilometres each night. Most people never notice them.
'They're incredible,' he said. 'Tiny things, not much bigger than a monarch butterfly. They live 28 years, eat everything from mosquitoes to mayflies, and they even sing.'
He's recorded them gathering under a single tree, mid-hunt, 'like it's a bar,' all chattering away.
They're also turning up in unexpected places.
'A 92-year-old farmer laughed when I asked to put a recorder on his land. He said, 'I've lived here my whole life. Never seen a bat.' Turned out he had plenty.'
The project's long-term goal is to locate maternity roosts – old trees where pregnant female bats cluster together in summer to raise their young.
'These bats might only have one pup a year,' Henderson said. 'If we can find and protect those trees from rats, possums and feral cats, we're giving them a real chance.'
And because the solar monitors require almost no maintenance, they make long-term tracking possible – not just for scientists, but for citizen volunteers too. Many start with no experience, just curiosity and a willingness to learn. But it's that steady commitment over time that helps build a clearer picture of where bats live, feed and breed.
'We've got so many older volunteers with time and energy. If I can say, 'Hang this up, check it now and then, no batteries needed,' it becomes something they can do. That's the buzz.'
Kaipātiki Project is more than a bush group. Based at the edge of Eskdale Reserve in Auckland North, it's a thriving EcoHub where ecology meets mātauranga Māori. The group runs programmes in native plant propagation, food resilience, glowworm monitoring and zero-waste education.
'We want people to really see what's around them,' he said. 'COVID forced people into their local parks. For some, it was the first time they noticed the trees.'
That reconnection is what Kaipātiki Project hopes to nurture. 'Our job is bringing nature back to people, and people back to nature.' For Henderson, the true win is when curiosity turns into care. 'When someone takes a recorder home and starts asking the right questions? That's when I know something's clicked.'
To him, climate action isn't just about cutting emissions. It's about paying attention to what we're protecting. 'Don't just go out and kill a bunch of rats and call it conservation,' he said. 'Ask: are the birds coming back? Are the bats staying? If we measure it, we can protect it.'
Solar-powered bat monitors might not sound revolutionary. But for Kaipātiki Project, and for the bats flying quietly through Auckland's twilight, they're helping light the way.
To explore Kaipātiki Project's community work and environmental programmes, visit kaipatiki.org.nz.