The area around Ōtautahi | Christchurch supported an abundance of birdlife when the area was settled by the British in 1850. Swamp drainage for city building, and the introduction of predatory mammals, has, however, resulted in a drastic decline of many indigenous species, including the iridescent honey-eating tuī (above). Since the 1990s, Christchurch City Council, the University of Canterbury (UC) and community groups have worked hard to re-establish these populations through habitat restoration and predator control.
The university’s Biodiversity Plan 2022-2025 established targets to enhance biodiversity including to increase native bird populations on campus. Alongside actions such as increased native plantings, sowing a wildflower meadow to boost insect diversity and “low mow” zones to provide habitat for invertebrates, a critical component of the plan is reducing introduced predators.
- THE podcast: educating our way out of the climate crisis
- Teaming up with students to design sustainability education
- Bringing in alumni as guest tutors to teach and inspire students
Here’s how UC has engaged with conservation and community groups to reduce predators and provide students with diverse opportunities to develop skills and improve their well-being in the process.
Predator control work begins
Surveying for pests on campus confirmed a mix of predators – rats, mice, hedgehogs and possums. A trapline was planned, which aligned with the Department of Conservation’s humane predator control protocols for Aotearoa New Zealand. Around the same time, students approached the Sustainability Office with a request to begin trapping predators, so the timing was perfect.
UC’s Sustainability Office partnered with the Riccarton chapter of Predator Free New Zealand (PFR) and the Environmental Science Society student club, EnviroSoc, and in 2023, 34 trained students formed a weekly roster to maintain and clear the trapline. By 2024, more than 45 students were participating enthusiastically, with all three waterways on campus now serviced by traplines.
Fewer rats, possums, hedgehogs and mice
Bird nests (see below) have been monitored on campus for many years, providing good baseline data. With no other interventions taking place, since the predator trapping programme has been established, the nest survival rate on campus has shown a significant increase. In two years, 747 pests have been trapped on campus and in the local Riccarton area: 514 rats, 26 possums, 52 hedgehogs and 167 mice. Native bird nests’ survival rate has leapt, from 6 to 22 per cent prior to trapping to 63 per cent, a trend that is continuing.
Why do students participate?
While many of the volunteers study biological or environmental sciences, students from geology, geography, sustainability, psychology, engineering and law also participate. They are all keen to take action to improve the environment and undo degradation. Trapping provides an option that they can conveniently join on campus. In addition, they learn valuable skills, such as best practices for trapping, health and safety procedures, and Department of Conservation (DOC) techniques for monitoring pest species.
An unexpected bonus is the opportunities for students to connect with like-minded peers through working in small groups, which provides a welcoming space for those with social anxieties. Spending time on the beautiful UC campus observing the plant and birdlife is also great for well-being.
Resourcing considerations
Inductions, including health and safety, and training, takes 1.5 hours, with groups of two to six students. Some students have experience with trapping, while others are completely new and need to be placed with more experienced trappers until they build their confidence and skills.
Recruiting students has not been difficult and has been largely carried out by EnviroSoc. Meetings with the team are monthly owing to students’ study commitments, field trips and exams, with communications mostly on email and social media. The students, under the guidance of Hannah Whittall, a environmental science major with honours, organise themselves to maintain and clear the traplines, have shown a real professionalism in the way they have performed, and have been crucial to the success of this project.
The total cost to establish the programme has been about NZ$6,000 (£2,745), funded through the Sustainability Office’s annual budget. The cost to continue the programme is NZ$1,200 annually.
PFR build trapping boxes at community workshops to promote and advocate for “backyard trapping”, and sell these to interested parties, including UC, to cover costs.
Collaboration is key
The UC biodiversity advisory committee oversees and guides this project and is composed of academic and professional staff and one student representative. Several academic staff have provided further guidance and supervised a public workshop in their specialty fields. Engagement with other institutions to share results and lessons has been managed by PFR lead Jade Humphrey, a geology PhD candidate.
Dreaming of tuī
In late 2023, a Trapping, Tracking and Triumphs hui was held on campus, as a collaborative event between UC, EnviroSoc and PFR. The gathering brought together more than 60 community members: UC students, staff, primary- and secondary-school students, teachers and others involved in predator control and other biodiversity programmes. This was an opportunity to connect, reflect and celebrate together. The school students were particularly proud to share why they were getting involved in predator control and what outcomes they hoped to achieve. Many dreamed of seeing the native tuī return to Christchurch; the native bird was lost to the area decades ago through habitat loss and introduced predators. By continuing to trap invasive predators and restore native habitats at UC and across the city, such dreams can become reality.
Seamus Moran is biodiversity coordinator at the University of Canterbury.
If you would like advice and insight from academics and university staff delivered direct to your inbox each week, sign up for the Campus newsletter.
comment