Dune-dwelling hedgehogs
This article was published in the Mangawhai Focus, June 2025.
A new research project supported by the Shorebirds Trust is helping shine a light on one of Aotearoa New Zealand’s most underrated introduced predators. Often seen as harmless garden visitors, hedgehogs are, in fact, skilled predators with a taste for native wildlife including bird eggs, chicks, lizards and insects. For coastal communities like Mangawhai and Pākiri, where precious dune ecosystems support rare species, hedgehogs are a serious conservation concern.
In line with the Shorebirds Trust’s three guiding pou (pillars) – partner, research and restore – the trust recently supported a master’s research project by Erica Paterson. Her work focused on understanding hedgehog behaviour in dune habitats, using GPS trackers to monitor their movements.
The results are eye-opening. Hedgehogs tracked in Erica’s research had a mean home range of 7.1 hectares, with nightly travel ranges of 3.5 ha. Incredibly, one female hedgehog was even tracked travelling over four kilometres in a single night – the longest distance ever recorded!
It demonstrates they are incredibly mobile animals. Understanding their movements will help to design smarter conservation strategies to protect our native species.
And the stakes are high. Iconic ground-nesting birds like the critically endangered tara iti (fairy tern), tūturiwhatu (NZ dotterel), and tōrea pango (oystercatcher) are particularly vulnerable to hedgehog predation. So, too, are native lizards like the shore skink and countless invertebrates – one past study found a single hedgehog with 283 wētā legs in its stomach.
Local conservation efforts are already making a difference. On the Tara Iti Golf Club property, which is managed as an ecological sanctuary, more than 1600 hedgehogs have been removed. At the start of trapping nearly 300 a year were caught. Thanks to these efforts, breeding success for threatened native species like tūturiwhatu have significantly improved. But with over 100 hedgehogs still caught there annually, the threat remains.
Erica’s research offers practical insights for conservation managers and community trappers, including recommendations to tighten trap spacing and focus efforts during peak movement months, helping trappers make their work even more effective. With hedgehogs being so mobile, this research reinforces the need for landscape scale predator control across our communities. And with less than 30 per cent of our dune ecosystems remaining, this work is critical to guide and improve conservation efforts.
The Shorebirds Trust believes research-informed, community-driven conservation is the key to protecting what makes our coastal communities so special. There are many ways you can play a part, including undertaking predator control, local dune planting and weeding days, and giving coastal species space to feed, breed and rest. We look forward to sharing more locally based research!