A 12-year-old’s after-school habit of poking around the creek behind his house has put one of New Zealand’s rarest native frogs on the map several hundred kilometres south of where conservationists thought it lived.
Rumi Lourie was exploring a small Lower Hutt waterway when he spotted a distinctive little frog tucked under a rock. He picked it up gently, took a closer look at the eyes, the ridge across the head and the patterning on its back, and quickly realised this was no ordinary garden visitor. He named the frog Tank.
What he had found, the Department of Conservation has now confirmed, was a Hochstetter’s frog, one of four surviving species of pepeketua endemic to Aotearoa, and a small living relic of a lineage so old it was hopping through the forests of Gondwana long before mammals reached this part of the world.
According to reporting by 1News, three frogs in total were discovered at the Lower Hutt creek, both juveniles and adults, which means a small population has been quietly breeding in the city for the better part of fifty years. It is the first confirmed sighting of the species south of the King Country.
DOC biodiversity ranger Pattern Reid said the find was a genuine surprise.
“They’re well outside of their natural range, which is Waikato and northwards,” she said.
She described the discovery as a “very, very cool” one for the department, which is now arranging genetic testing to work out which of the wild populations the Lower Hutt frogs are most closely related to.
Hochstetter’s frogs, known to scientists as Leiopelma hochstetteri, are normally found in cool, shaded, damp gullies in pockets of the upper North Island, on the Coromandel, and on Aotea Great Barrier Island. They live alongside and sometimes inside slow-flowing streams, reach only a few centimetres in length, and have an unusual life history. Unlike most frogs in the world, the Leiopelma genus has no eardrum, does not croak in the conventional sense, and largely bypasses the free-swimming tadpole stage, with froglets developing inside the egg and hatching with limbs already formed.
So how did three of them turn up in a Wellington suburb? The trail leads back to biologist Dr Ben Bell, a long-time researcher of New Zealand’s native frogs, who lived near the creek in the 1970s and was breeding Hochstetter’s at the time as part of a research programme.
“I found three had escaped during a flood,” Dr Bell told 1News.
Two of those escapees came from a Coromandel collection and one from East Cape. Half a century later it appears their descendants have not only survived in the Lower Hutt bush but have built up a small, self-sustaining colony, exactly the kind of accidental rewilding that conservation managers usually only get to fantasise about.
For Rumi, who has been catching skinks, weta and the odd eel in the same creek for years, finding Tank felt like a serious stroke of luck.
“It’s quite special, and like, quite lucky to have found them,” he said.
He also gave a careful, almost zoological description of his find, noting “the little eyes, saw the bridge on his head, and the colours on his back”, details that any DOC officer would have recognised straight away as the giveaway features of a native Leiopelma rather than an introduced Australian whistling frog or a southern bell frog.
The discovery has more than feel-good value. Hochstetter’s frog is the most widespread of the four remaining native species, but it is still classified as At Risk and Declining under DOC’s threat classification system. Predation by rats, stoats and possums, habitat loss, sediment in streams from forestry and farming, and the chytrid fungus disease that has hammered amphibians worldwide have all chipped away at populations across its known range.
A small, isolated, decades-old colony in an urban catchment hundreds of kilometres south of the species’ main strongholds is therefore genuinely unusual. If the planned genetic testing confirms the Lower Hutt frogs descend from the escaped breeding stock, conservation managers will need to decide what to do with them. The options range from leaving them in place as an inadvertent insurance population, to translocating them back into their original ranges, to treating them as a hybrid Coromandel and East Cape lineage that no longer exists in the wild in that form anywhere else.
Local conservation volunteers have already been encouraged to keep an eye on similar small streams in the Wellington area, although DOC has been deliberately vague about the exact location of the discovery to give the new colony breathing space and to keep curious visitors at a distance.
Pattern Reid said the takeaway for Wellingtonians was a simple one. The country’s native wildlife is sometimes hiding in surprising places, and people who spend time outside paying close attention, like Rumi, are still the ones most likely to find it.
Have you spotted unusual native wildlife in your part of the country, or do you know of small streams that might be worth a closer look? Share your stories in the comments below.
This article was written by AI, briefed to report the facts, hopefully without some of the bias people bring to the job π
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