Urban Wildlife Connectivity through NatureLinks

Main Club, 1st April 2022

Our speaker was Dr Jane Chambers, Senior Lecturer in Environmental and Conservation Sciences at Murdoch University and Director of NatureLink Perth. NatureLink Perth is a community of practice working together to integrate nature into the city and connect people to nature, with other benefits such as cooler spaces and healthier people.

Jane spoke about the first goal of NatureLink Perth, which is to create ecological links throughout the Perth metropolitan area. Perth and Peel are described as species hotspots within the SW biodiversity hotspot and need to be protected. Clearing and fragmentation have resulted in only 40% of banksia woodland remaining, in 12,000 patches, like islands, with an average of 1.6ha. Since most reserves are not big enough to sustain biodiversity into the future, one way of preserving biodiversity is to create links between them.

The NatureLinks project covers an area from Yanchep to Mandurah and from the coast to beyond Mundaring. The areas have been mapped according to their risk rating, from forests and bush reserves to hostile areas such as freeways. (State Forest is not included because there is no guarantee that it will be there in the future.) These areas have been carefully joined by lines that follow the least cost for the animal – the quickest and safest routes between them. (These are defined as linkages – not corridors, which must have a certain width to be defined as such.)

It is suggested that households living along these linkages grow biodiverse native gardens to facilitate the movement of animals between patches of bushland. (However, there is a danger of attracting wildlife close to busy highways, where road kills can occur.) Road verges along the linkages need trees and native shrubs, rain gardens (capture stormwater) and swales planted with sedges.

Animals, and even plants, have an Environmental Distance Threshold (EDT), which depends on their mobility. For example, a Peacock Spider can only travel <50m, but a Quenda can travel 500m and a Carnaby’s Cockatoo >1500m. (Jane calls this “little feet to wide wings”.) A plant’s distribution of pollen and seed usually depends on wind, insects, or birds, so a plant’s EDT depends on the EDT of those things.

Animals need food, shelter, and protection. So, Jane’s recommendations to us all are as follows:

  • Create biodiverse gardens with complex habitat that includes trees, local native plants, mulch, rocks, water, shelters, and roosting sites to cater for different kinds of animals, large and small.
  • Drains can be re-vegetated to make living streams, and backyards can include frog ponds.

Jane strongly recommends that we look at two websites:

ReWild is supported by Perth NRM, Birdlife Australia and Lotterywest. ReWild has tips on how we can help build that much-needed connectivity ourselves, and NatureLink has a map of Perth showing the links, and by zooming in, we can find the nearest link to our own home.

Mike Gregson