Keeping track of our city rat population
We’ve been waging war on rats for a while – but how do we know if it’s working?
It’s impossible to know exactly how many rats there are in Taranaki, no-one has yet figured out how to get them to stand still for a headcount!
But there are monitoring methods that give a reliable indication of trends over time.
Since we launched the Towards Predator-Free Taranaki project in 2018 rats have been the main target in urban areas, with stoats and possums the focus elsewhere.
So this month, for the fifth April in a row, the team will place pre-inked and baited tracking tunnels at the same 100 locations across New Plymouth, mainly public parks and walkways. This year we are also monitoring in Bell Block, Inglewood, Stratford and Oākura.
The next morning they will return to check the cards. If a rat has entered the tunnel, it would have stood in the ink and left easily recognisable prints.
In 2018 a third of the tunnels contained rat footprints. That dropped to 19 per cent in 2019 then rose to 26 per cent in lockdown-affected 2020.
Last year it dropped to a pleasing 9.8 per cent.
This year we hope to another decline.
Along with analysis of data see from Trap.nz, community engagement and monitoring of biodiversity outcomes, this tracking gives us a useful steer on how the project is going and where we need to focus our attention.
The lessons we learn also improve how we roll the project out to other towns such as Eltham and punake, communities already doing great mahi when it comes to protecting our native biodiversity.
Finally, a heads up. As we head into winter rats will seek out warm, dry homes. As well as causing damage to property, they can carry disease.
The good news is cold makes rats hungry, so make sure your traps are set and freshly baited.
For more information, go to the Towards Predator-Free Taranaki website or Facebook page.
Steve Ellis is the Taranaki Regional Council Environment Services Manager.
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