New Zealanders have the highest rate of cat ownership in the world - but unfortunately our feline friends are a major contributor to native biodiversity decline. Photo / Thinkstock
As officials mull whether feral cats should be added to the hit list of our Predator Free 2050 mission, a new review has laid out the biggest knowledge gaps still facing efforts to manage the animal.
Study co-author, Manaaki Whenua-Landcare Research wildlife ecologist Dr Al Glen, said how to tackle the ecological impacts wrought by an animal widely loved and valued in New Zealand made for a “difficult balancing act”.
“Our wildlife evolved without mammal predators, which means they’re far more vulnerable than wildlife in most other parts of the world.”
Feral cats, particularly, have long proven themselves ferocious predators - killing native birds, bats, lizards, wētā and other insects – while spreading toxoplasmosis to other animals and humans.
But this designated pest, thought to number 2.5 million in New Zealand, was just part of the problem.
Aside from the estimated 200,000 stray cats wandering our towns and cities, nearly half of Kiwi households own at least one domestic cat – and 20 per cent own two or more.
Glen and colleagues decided to look at all three of those types together and pinpoint what further research was needed around each.
One key issue was that, as with stoats, New Zealand still didn’t have cost-effective ways of monitoring feral cats, or how far juveniles could disperse.
The study explored the effectiveness of different techniques such as camera trapping, footprint counts and wildlife detection dogs, finding various pros and cons.
It also discussed the need to develop more effective lures and kill traps for feral cats and, importantly, to develop procedures that could distinguish owned cats from unowned ones.
That might require new legislation requiring owned cats to be registered and microchipped in the same way dogs are, the review found, but public acceptance would be needed first.
Glen saw social licence as being fundamental to the wider issue – and much research would be needed to gauge views among different groups.
“The risk is, if the public are not onboard and we don’t have public support for what we’re doing, then there might be all sorts of problems, ranging from political opposition, through to people deliberately sabotaging management equipment,” he said.
“It’s really important to give a clear message that this is about managing the harmful impact of cats – which does not equate to getting rid of all cats.”
With the issue having been in the spotlight since the Morgan Foundation launched its controversial Cats to Go campaign a decade ago, Glen felt there was now more awareness among Kiwis about responsible cat ownership.
“It’s now more common to hear people say they’re keeping their cats indoors, or in an enclosure in the gardens, so they’re not out hunting wildlife ... so I think we are moving in the right direction.”
“We’d be jumping ahead to say this is how we need to manage them.”
The paper comes as the Department of Conservation is planning to review its Predator Free 2050 strategy next year, with a goal of having a revised one in place by 2025.
DoC’s senior manager for the programme, Brent Beaven, said that work would address whether feral cats or other introduced predators should be included in the strategy, which currently targeted rats, possums and stoats.
“Consulting with the New Zealand public about any changes to the strategy will be an important part of the review process.”
National leader Christopher Luxon has already signalled his support for feral cats joining the kill list, as has the South Island’s Southern Lakes Sanctuary conservation group.
The Predator Free New Zealand Trust has meanwhile called for a “National Cat Act” involving compulsory de-sexing and microchipping.
Jamie Morton is a specialist in science and environmental reporting. He joined the Herald in 2011 and writes about everything from conservation and climate change to natural hazards and new technology.