Farmer ‘stunned’ to discover new population of ‘critically endangered’ species in NZ

John Evans stumbled upon something remarkable in the mountainous reaches of New Zealand’s South Island this November.

Evans, a farmer and naturalist, was clearing traps in Ashburton Lakes — about 80 miles west of Christchurch — when he noticed a trio of tiny beetles clinging to a speargrass plant. Brown and bumpy, the insects were not much larger than a fingernail.

After snapping several photos, he posted them to a Facebook page dedicated to identifying bugs, which sparked intense interest from entomologists.

Department of Conservation (DOC) staff were quickly alerted and dispatched to the area in December, where they observed 41 additional beetles.

It turns out, Evans had happened upon a new population of Canterbury knobbled weevils, a critically endangered species, according to a Dec. 20 news release from the DOC.

“As a farmer I’m used to looking at insects,” Evans said. “I was like a stunned mullet when I learned these were such a rare species.”

‘A huge boost’

Canterbury knobbled weevils are a rare species of weevil — small beetles with distinctive snouts — which are endemic to the South Island, according to iNaturalist, a citizen scientist platform.

Considered a Lazarus taxa, they were previously believed to have gone extinct about 100 years ago. But, they were rediscovered in Burkes Pass — about 50 miles from Ashburton Lakes — in 2004.

Prior to Evans’ finding, the weevils were only thought to have the one population in Burkes Pass.

“The discovery is a huge boost for the species,” conservation officials said, noting that the “Burkes Pass population has been in decline, and is thought to be down to critically low numbers.”

Habitat loss caused by the growth of agriculture is believed to have contributed to the weevils’ decline. The insects, which feed on speargrass, are likely also threatened by non-native mammals, such as hedgehogs, rabbits and mice.

While the second population is undoubtedly welcome news, the species could still be on shaky ground, Tara Murray, a DOC science adviser, said in the release.

“At this stage we don’t yet know how big or secure the new population is,” Murray said. “Both populations are small, so they could easily be wiped out by fire or a few years of bad growing conditions for the speargrass plants they rely on.”

The DOC has allocated funding to assist in conserving the species, which is protected by law.

This story was originally published December 27, 2024 at 4:41 PM with the headline "Farmer ‘stunned’ to discover new population of ‘critically endangered’ species in NZ."