One of New Zealand's most hated pests could come in handy during a locust infestation, new research indicates.

The Waikato University study, being carried out by psychology student Kristie Cameron as part of her PhD research, found locusts were the meal of choice for possums.

Ms Cameron designed the study to find out which foods possums preferred, and how far they would go to get it.

Each possum used in her research had two food delivery systems attached to their cage.


To access a food item for two seconds, a possum had to tap a lever a predetermined number of times.

"Some possums had a paw-bias [in] that they'd use their right more than their left. So I had to teach them to tap the levers with their nose," Ms Cameron said.

Different items of food were placed in the feeding tubes forcing possums to pick the one they preferred most.

The number of times possums had to nudge levers also varied, meaning the animals had to put in more effort for different types of food. The results were then be recorded on a computer for analysis.

Ms Cameron said: "The maximum a possum would press the lever was 512 times for two seconds' access to locusts, and a possum could hit the lever more than 2000 times in a session."

Results also showed some possums were "lazier" than others - except when locusts were involved.

"I wanted to know at what point they'd give up and change to the other lever to the more easily accessed but less tasty food," she said.

Information from the study may help in achieving greater possum control with results indicating which foods could best be used to lure the animals away from foliage, Ms Cameron said.


The results of two experiments used in Ms Cameron's study are due to be published in the International Journal of Comparative Psychology next month.

Eight experiments were performed as part of her research.