Seeing rare pink grasshopper ‘so exciting’

An "exceptionally rare" pink grasshopper was found by Department of Conservation rangers during...
An "exceptionally rare" pink grasshopper was found by Department of Conservation rangers during Doc’s annual grasshopper survey. PHOTO: DOC
Department of Conservation ranger Jen Schori could not believe her eyes during an annual grasshopper survey near Lake Tekapo/Takapō in the Mackenzie Basin.

There, sitting on the grey stones in the bright sunshine, was a deep pink female robust grasshopper (Sigaus robustus).

"I’ve been studying these amazing creatures for years. They are usually grey or brown coloured like river stones. I’d heard rumours about a pink one but never seen one myself. It was so exciting," Ms Schori said.

"Pink grasshoppers are exceptionally rare. It’s likely caused by a genetic mutation called erythrism, which results in an overproduction of red pigment and less of the usual natural pigment that the species has."

The robust grasshopper is New Zealand’s largest lowland grasshopper and is only found along the edges of the braided rivers of the Mackenzie Basin.

The grasshopper comes in many shades of grey and rusty brown, matching the stones and silty soils in its habitat. It is classed as nationally endangered, and is at risk from predators such as hedgehogs, cats and birds.

"These grasshoppers are so unique. They look almost prehistoric. They can jump fairly well but are renowned for their clumsy landings. They’re also very vulnerable. The pink one will unfortunately stand out even more to predators, which is why this sighting is so special."

In 2018, with funding from Te Manahuna Aoraki, a predator exclusion fence was put up around a small area of grasshopper habitat in the Mackenzie Basin.

It is thought to be the world’s first exclusion fence built specifically for the protection of insects and to learn more about them.

The pink one was in a different site outside the fence and would have to fend for herself, Ms Schori said.

"They do live up to their name — they’re quite robust and the females are double the size of the males. Maybe she will breed, and we will see some more pink ones.

"She has certainly become a bit of a celebrity in our office and we joke about the paparazzi coming and taking loads of photos. I’m just so happy I got to see one after all these years. Getting out naturing in this part of the world is really special." — Allied Media