Rat numbers down in New Plymouth

Tuesday 13 June 2023, 11:02AM

By Taranaki Regional Council


Nick Heslop checking card
Nick Heslop checking card Credit: Taranaki Regional Council


New Plymouth has far fewer rats than it did five years ago, thanks to the efforts of thousands of dedicated backyard trappers.

Towards Predator-Free Taranaki recently carried out its annual rat tracking monitoring at nine sites across the city. At each site 10 tracking tunnels were baited with peanut butter and left out for one fine night. In the morning, prints on an inked card revealed whether there were rodents or other creatures present.

This year rats were detected at just 13% of the tracking tunnels, compared to 36% in 2018 and 16% in 2022.  There have been significant improvements at several locations, with the Herekawe Stream site dropping from 70% to 10% and Huatoki Walkway from 60% to 10%.

Programme Lead Nick Heslop says while there is still a lot of work to be done, New Plymouth is already seeing the benefits of fewer rats.

“We’re hearing story after story of abundant birdlife in backyards and gardens, which is backed up by bird count and survey results.

“As a community we can feel proud of how far we’ve come. On average there are traps in more than one in five New Plymouth households, although there are still hot spots across the city where more work is needed.

“Hundreds of volunteers are working with New Plymouth District Council to maintain traps in our parks, walkways and reserves.

“And schools and tamariki are among our biggest supporters, which bodes well for the future.”

The good news does come with a slight downside, Mr Heslop says.

“With fewer rats in the ecosystem, we have seen an increase in mice. This is not unexpected and is being seen across the country.

“The good news is that due to their size, mice don’t do as much damage to our native ecosystems or properties as rats however they are still a threat to invertebrates and native lizards.”

With the winter months upon us, mice will be venturing inside in search of food and warmth.

 “We encourage people to keep up the rat trapping but also take steps to remove any mice they have around.”

Rat traps such as the T-Rex are not calibrated for mice, so Mr Heslop recommends a couple of mouse traps from the supermarket or hardware store.

“For bait, you can’t go past good old peanut butter or even a dab of mayonnaise, which mice and rats love.”

The Towards Predator-Free Taranaki team also carried out annual possum monitoring in New Plymouth recently, with results expected to be released within the next two weeks.

To stay up to date go to or check out the Towards Predator-Free Taranaki Facebook page. If you’re in New Plymouth and interested in becoming a volunteer park trapper, contact at NPDC.