Peanut butter, chew cards and community commitment: a recipe for a pest-free Kaipātiki

Charlie Brown

Pest Free Kaipātiki Citizen Science Reporter

Fiona Smal, Senior Restoration Advisor and Tamilla Todd, Intern, analysing chew cards

The Kaipātiki region encompasses over 450 hectares of ecologically valuable parks that serve as habitats for native birds, insects, and plants, as well as providing recreational enjoyment. Sadly, introduced pest animals pose a serious threat to our local ecosystems.

PFK monitors pest animal populations through its chew card campaign. This campaign has taken place across 44 reserves in Kaipātiki since 2017, allowing for long-term trends in predator numbers to be tracked.

The chew card campaign is a fun, easy way to get involved with citizen science and learn about pest mammals around Kaipātiki.⁠ Around July every year, over a two-week period, about 800 chew cards are laid out and collected by community volunteers.

Chew cards are small corflute cards attached to trees, filled with a peanut butter-scented lure to attract pest species such as rats, stoats, possums and hedgehogs. The bite marks on the cards left by their nibbles are then analysed to determine what animal has chewed the card.

The results of this citizen science project clearly show that where there is consistent volunteer predator control, there are far fewer pest numbers. Averaged across all monitored reserves in Kaipātiki, mouse, rat and possum populations have declined, which is hugely encouraging for local conservationists and volunteers.

Birkenhead War Memorial Park is one such park that recorded no rat presence in the 2024 chew card data. While we can’t definitively say there are no rats, the evidence strongly suggests that their population numbers are very low. Philippa, a volunteer from PFK’s Birkenhead War Memorial Park Reserve Group says, “We are thrilled with the results. We feel that establishing a reserve group for the park has made a real difference."

Shepherds Park has strong volunteer involvement and has shown a substantial reduction in relative rat abundance since the survey was first carried out in 2017. By comparison, parts of Hellyers Creek Reserve, less than two kilometres in distance from Shepherds Park, currently has no volunteer activity and saw much higher rat abundances over the same period.

The 2024 chew card analysis showed that certain reserves such as Woodcote Scenic Reserve, Takapuna Golf Course and Chelsea Estate Heritage Park recorded the highest levels of possum activity, suggesting that these areas may require more intensive pest control efforts in the future. With information provided by the campaign, it is far easier to quickly target possums with devices in parks, or indeed in the surrounding gardens of neighbours – if people join in the effort.

Steve, a PFK volunteer, has been able to see the results of his trapping first-hand; “Even if you think you don't have rats around your property, it's very likely you will. It's easy to get resources from PFK to help. I trap because I want to increase the native bird population. Hearing the dawn chorus and ruru at night is magical.”

Hosting a trap with PFK support has added community benefits. Angela, a volunteer says; “I've recently moved to Birkenhead and hosting a trap has meant that I've come to know my neighbours through my reserve group quickly. It's a great way to build community while doing some good for the environment. Hosting one trap is minimal effort for a big reward!”

The chew card campaign findings demonstrate that community involvement makes a measurable difference in reducing pest numbers and protecting native biodiversity.

While the trend in pest population reductions is positive, it also highlights that further effort is needed. Kaipātiki’s large and diverse ecosystems create ideal conditions for pests to thrive and without sustained management, predator populations can quickly rebound.

Thanks to sponsorship from the Kaipātiki Local Board, Auckland Council and other supporters, PFK provides traps, training and resources to support local individuals and community groups to manage pests on and around their properties within the Kaipātiki Local Board area.

If you would like to contribute to the restoration of our precious native ecosystems, there are several ways to get involved:

• Join PFK for this years’ chew card campaign and volunteer a short amount of time to lay out and collect chew cards. Register your interest by emailing team@pfk.org.nz

• Join an existing volunteer group or establish a new predator control line. PFK can connect you with local volunteers or help to identify priority areas and supply equipment.

• Attend a community tool shed open day at 3 Ross Avenue, Glenfield, held every second and fourth Saturday of the month (9 am – 11 am). Here, you can borrow a device for your garden, learn to handle them and ask experts for guidance.

• Keep an eye out for local events, especially a concentration of animal pesty topics during PFK’s ‘Pestival’ – taking place from April to August this year!