A new population of a critically endangered beetle has been discovered after 20 years in “magnificent news” for the species’ long-term survival, the Department of Conservation says.
Naturalist John Evans was out clearing traps in the Ashburton-Lakes area late last year when he came across three distinctive-looking weevils.
“My curiosity got the better of me and I stopped and managed to get them before they disappeared and took a photo and thought ‘this is big’… I’ve been farming for 50 years so I know what a weevil looks like,” Evans told 1News.
And so began his hunt for more information.
“Got home and put it on the Facebook page and messages says don’t tell anyone where that is and put it on iNaturalist and all hell broke loose,” he said with a laugh.
Soon, the possible discovery of Canterbury Knobbled weevils was on the Department of Conservation’s radar.
DOC technical advisor Warren Chinn said staff raced out to the Ashburton-Lakes area to see it for themselves.
“Sure enough, there they were and within two-and-a-half hours, we found 41 weevils,” he said.
“That’s a catch rate that’s just unprecedented for any rare and threatened invertebrate, so I was just absolutely stunned. It’s magnificent news.”
The team took specimens away with them to confirm the identification was indeed the Canterbury Knobbled weevil.
“[Evans] found a long-lost population of the weevil which is akin to the takahē in the Murchison Mountains,” Chinn said.
Evans said his unlikely find came as quite the shock.
“The entomologists of the world are really excited so it’s sort of rubbing off – a bit like a stunned mullet, really, about what the hell’s going on.”
The discovery is a huge boost for the species, which until now had only been known to live in one other area at Burkes Pass near Tekapo, about 80 kilometres away.
Before they were first discovered in Burkes Pass in 2004, the Canterbury Knobbled weevils were believed to have long been extinct.
Chinn said DOC had “focused all our attention for several years” on monitoring the population and how best to “get an insurance population established elsewhere”.
“Lo and behold, an insurance population presented itself,” he said.
Chinn said their focus has now turned to how best to protect them.
“Find out how far and widely spread they are and then work out a regime of fencing to prevent herbivores from getting in – hares and rabbits and so forth – and then, of course, we will need some kind of a tracking network for number one predator which is hedgehogs.”
