Nature in the city: how to protect Perth’s Banksia woodlands?

Cities all over the world are facing the challenge of balancing urban growth and conservation. For a city like Perth, which is located within one of the world’s thirty-six biodiversity hotspots in the southwest corner of Australia, addressing this challenge is vitally important. 

Within and surrounding the city of Perth is a beautiful and biodiverse ecosystem known as the Banksia Woodlands. This ecosystem, which is situated on Noongar country, is incredibly important both culturally and ecologically. Altogether, the Banksia Woodlands support a huge diversity of native fauna and flora, including over 20 nationally Threatened species such as the grand spider orchid (Caladenia huegelii), the western quoll or chuditch (Dasyurus geoffroii), and Carnaby’s black cockatoos (Calyptorhynchus latirostris). Unfortunately, while there are still pockets of Banksia woodland throughout the city of Perth, more than 60% of this ecosystem has been cleared, mainly for urban development. 

Concerned researchers from all over the southwest have worked together to explore the current threats to this important ecosystem and how best to conserve it, in a new review published recently in the Australian Journal of Botany.

It’s not the first time that a group of concerned researchers have examined the threats facing this ecosystem. Back in 1989, the Royal Society of Western Australia hosted a Banksia Woodlands Symposium and experts there agreed: “Because of their proximity to Perth, Banksia woodlands are being destroyed at a rapid rate.” So now, more than 30 years on, what is the current state of Perth’s Banksia woodlands? Based on the 1989 Banksia Woodlands Symposium, 29 researchers have joined forces to share what we currently know about this ecosystem, what’s left to learn, and what steps are needed to conserve remnants throughout the city of Perth.

Dr Alison Ritchie, the lead author on the new review, said that many of the threats recognised during the 1989 symposium continue to be an issue today, however, there are also new threats to consider.

“Climate change wasn’t acknowledged in the 1989 review, but it’s a major challenge to the conservation and restoration of Banksia woodlands and the species they support,” Dr Ritchie said. “Predicted declines in rainfall and increases in temperature, as well as the ‘heat island effect’ where remnants are surrounded by hot reflective surfaces from urban infrastructure, will all exacerbate and interact with many of the threats that Banksia woodlands already face, such as plant diseases, invasive species, and changing fire regimes.” 

The new review also discusses the importance of a relatively new field of research: ecological restoration. 

“Back in 1989, ‘restoration ecology’ wasn’t even a discipline yet,” Dr Ritchie said. “Now, more than ever, we need to be considering how to best restore disturbed sites and bring back ecosystem functioning. There’s been considerable research and progress in this field in recent years, including recognition of the role that new technologies and engineering innovations can play. For example, flash flaming native seeds to remove florets and improve germination success is one new technology that’s becoming a vital tool for large-scale restoration efforts.”

With such a biodiverse treasure on their doorstep, it’s unsurprising that many people within Perth care deeply about our Banksia woodlands and want them to be protected, as evidenced by the 2017 Beeliar Wetland protests. In 2016, the Banksia Woodlands were federally listed as a Threatened Ecological Community, however, an independent review of the Environment Protection and Biodiversity Conservation Act 1999 published in January this year found that the Act currently “does not enable the Commonwealth to protect and conserve environmental matters that are important for the nation” and is “not fit to address current or future environmental challenges”. 

So what can be done about it? Dr Ritchie and her co-authors acknowledge that more work is needed to build the bridges between research, policy, and practice, and that the public can and already do play an important role in protecting and conserving Banksia woodlands. 

“Our hope is that this review will serve as a foundation for future collaborative efforts between researchers, managers, and community organisations,” Dr Ritchie said. “By bringing these different areas of expertise together, we could help save this important ecosystem and ensure the Banksia woodlands and the growing city of Perth can coexist.”

To find out more, you can read the full review titled “A threatened ecological community: research advances and priorities for Banksia woodlands”, available Open Access in the latest edition of the Australian Journal of Botany.