Inconvenient truth

CATE TAUSS is principal botanist with Tauss and Associates Biodiversity Consultants, who has been working with the Friends of Manning Park Ridge.

SORRY, Francis Kotai, that you felt so confronted by my statement ”mountain bikes are shaping up to be the new bulldozer” (“Manning family adds their voice to ridge trails opposition,” Herald, April 2, 2022).

Unfortunately, The Chook did not quote me fully. 

As a plant scientist for over 28 years, mine was not a flippant, throwaway remark. 

I, too, was shocked after my spatial analysis of the existing, illegal mountain bike trails in Manning Park when I found they had, in the last few years, already cleared and otherwise degraded the equivalent of what Barnett’s bulldozers destroyed in the Roe 8 corridor in 2015-2016. 

It’s one of those inconvenient truths.

In Roe 8, the wide, raw wound through the bushland was seared into the memories of thousands of people who protested that ecocide. 

The damage on Manning Ridge is no less shocking, despite it being spread over a larger area than Barnetts cruel cut, and forming an intricate network of up to 15 km of trails. 

Mountain biking in this sense, could be called the new and sneaky bulldozer that is decimating bushland. 

The damage is  mainly done quietly, by shovels, at night, and without the clearing permits of Barnett’s bulldozers. 

You’re surely aware of the laws that prohibit illegal native vegetation clearing. However,  do you grasp the ecological concepts of fragmentation, edge effects, and unsustainable use of native bushland? 

The latter factors are firmly established in science as constituting some of the most destructive, environmental impacts on biodiversity and other natural heritage and ecosystem services that sustain life on earth.  


However, the master plans and blogs of mountain bikers make a habit of appropriating 

“sustainability” from the language of ecology: they use sustainability to describe how easy/economical it is to repair the built features of a trail, rather than how effectively the natural values (such as the size of a population of a rare species) can be maintained over time. 

Makes it confusing, huh?  Moreover, the many impacts of bushland fragmentation have been scientifically demonstrated to keep biting further and further over time, into the bushland if not promptly countered. 

Even then, on the scale of the Roe 8 debacle, such basic remediation requires a huge budget: millions of dollars from  government, countless hours of volunteer effort and  decades of skilled adaptive management in the Cockburn Community Wildlife Corridor. 

Yet, the City of Cockburn has consistently argued that, in effect,  they need to destroy more of: the Threatened Ecological Community (Honeymyrtle shrublands on limestone ridges of the Swan Coastal Plain); the critical (Parrot  Bush scrub) forage habitat of the Endangered Carnabys Cockatoo; and the Critically Endangered Tuart open forest and woodland, to win the funding to put a cheap band-sid on the existing bandit trails of Manning Ridge.  

What is even more concerning in all of the City of Cockburn’s mountain bike trail plans ― in the scaled-down version it now promises, or the full shebang of 21kms zig-zagging across Bush Forever Area 247  – so confidently proposed by Common Ground Trails Pty Ltd in 2020 – is that the City, Common Ground and bikers such as you and your colleagues have always operated in an environmentally and legally data-deficient bubble. 

The same goes for the massive ‘brownfield’ development proposed for the crests and western flank of Manning Ridge in the Cockburn Coastal Structure Plan and the Cockburn Coastal Drive (the latter being a  “road to nowhere”, a  throwback from Roe 8).


The City has funded numerous expensive, preliminary site assessments (such assessments are also called basic, reconnaissance or  Level 1 surveys by the EPA) of the Manning Park Bush Forever Area 247 in pursuit of their recreational makeover plan. 

Sadly, most of these reports did nothing more than to: re-hash the previous, stale, desktop data and blatant, technical mistakes made in the previous, superficial assessments of the footprint;  ignore or misrepresent most of the natural and indigenous heritage values; and shun any assessment of environmental  impacts. 

All pointedly ignored, or were technically incapable, of detecting the last intact occurrence (between Yanchep and Yalgorup) of the Threatened Ecological Community – Honeymyrtle shrublands on limestone ridges of the Swan Coastal Plain – that has been known, in the literature, to occur on Manning  Ridge since 2001 from the work of the late Dr Arthur Weston.

Francis, your opinion appears to condone the illegal activity and the City of Cockburn turns a blind eye to the bikers’ ongoing destruction (despite the City bearing the legal responsibility of managing and protecting Manning Park for conservation as a Bush Forever Area and as part of the Beeliar Regional Park). Is this the ”rational and  collegiate” approach you advocate? 

No, they are sad examples of why it is essential and urgent that an expert, fully informed, independent, publicly transparent and accountable assessment 

be made of the impacts by the WA  Environmental  Protection  Authority and the federal Department of Agriculture, Water and Environment under the relevant state and federal acts (including the WA Biodiversity Conservation Act 2016 and the EPBC Act 1999). 

Such due legal process is not a nuisance, as you suggest by claiming the referral of the Manning Park case under the EPBC Act would be just “trying to escalate it as a federal matter”. 

It is, already, a state and federal legal matter as important values that have the highest statutory protection are at stake. 

Leave a Reply