Offsets are meant to compensate biodiversity for threatening processes (clearing) in a ‘no net loss’ manner. How can that be a threat in itself?
According to the WA environmental offsets policy released in September 2011, offsets are only a last resort if avoiding the impact has been ruled out. All proposals for offsets need to be underpinned by ‘sound information and knowledge’.
How can anyone fulfil this requirement when we are offsetting habitat of a species for which we lack knowledge about major aspects of their ecology and biology? (Yokochi et al, 2015a)

Whenever an action was deemed to have significant impacts on wildlife, conditions for approval usually include some mitigating measures on site to soften the impact. However since the mid-1990s providing an environmental offset outside of the development area has become popular (Gleeson and Gleeson, 2012).
The idea behind this is trading a biodiversity loss in one location for an equivalent gain in another. 

The states have separate offset policies with differing methods for calculating offsets and predicting conservation outcomes. What they all seem to have in common is that land offsets are described in terms of a ratio – e.g. 5 new trees planted for 1 lost tree.  However, this overlooks the complexity of any habitat and in this particular example the time lag in establishing vegetation that will be of any use to wildlife.

The only adequate ratio would be the one that delivers the same conservation benefits as the lost area which is not only unrealistic, it is also close to impossible to calculate, particularly in advance.
Intensive monitoring over more than a decade was for example necessary to find out that a ratio of 19 to 1 was adequate to offset habitat loss for the green and golden bell frog when Olympic Park was built. (Evans and Maron, 2013)
Most developments do not get this level of publicity and they are neither underpinned by solid science nor do they quantify losses and gains with the affected wildlife in mind.

We cannot recreate a habitat in its biological diversity with all its associations and interdependencies and we usually have very little evidence to demonstrate how successful our offsets have been.
Monitoring and audit of offsets to safeguard that anticipated environmental outcomes are realised and enforcement of offset conditions if necessary should be guaranteed under the state’s offset policy. (Government of WA, 2014)

The first step towards better quality outcomes would be to enforce an independent environmental impact assessment and not having those reports written by consultants employed and funded by the proponent of the development. 

Western ringtail possums need a very specific habitat and the destruction of one of those last good habitat patches is a major loss for the species. Optimal patches with large populations are becoming unique and they are irreplaceable.

Any clearing also produces residual impacts such as fragmentation of habitat  and might lower the conservation value of the wider area which is usually not included in the calculation of the offset needed to come at least close to a true compensation. (Gleeson and Gleeson, 2012)

The location of an offset is probably the most important consideration when determining whether it mitigates the impact from a development. As there is hardly any prime ringtail habitat left in the core area, the newly created habitat will usually not benefit the population that is harmed on-site but at best a different population that can expand to the offset site.

The viability of the population affected by the development could be challenged unless habitat is found near-by with adequate vegetation which is not yet fully populated.  The offset could then consist of enhancement/repair of the adjacent habitat and the provision of linkages to the development area. 

There is also widespread criticism that some offsets result in little conservation gain even if they are located in prime habitat as they are unlikely to be cleared anyway and do not need further protection. (Gibbons and Lindenmayer, 2007)

Some offsets in the Busselton/Dunsborough area have resulted in extremely poor outcomes so far and long-term commitment to not only plant vegetation but to protect it (vandalism/neglect, weed control, feral animal control) and to monitor and make certain that the intended benefit is achieved is lacking.

In a number of local development projects such as that of Capecare in Armstrong Reserve in Dunsborough, approvals were granted without a suitable offset having been identified.  The native vegetation to be cleared had important and rare values and the offset was intended to provide like for like vegetation assemblages and native animal habitat.  However several years down the track a suitable offset has still not been found.
A mineral sands mine which will require the removal of several hectares of Whicher Scarp vegetation adjacent to a National Park has received EPA approval even though no offset had been identified. Even if there should be willingness to purchase land  in the vicinity with similar values, the problem most certainly is that this land does not exist or if it does, it will not be for sale.

There is something demonstrably wrong if rare and ever diminishing mature bushland in our region is approved for clearing by our agencies with no guarantees that the promised offsets can be found. We need a thorough review of these approval processes with the opportunity for community input.

Ecologist Professor Richard Hobbs called the practice of offsets ‘a Faustian pact’ as we run the risk of trading something irreplaceable for short term development gains with the mirage of having a good conservation outcome in the future through the offset.  (Maron et al, 2012).

The option of providing an offset opens the door to avoid costly, sensitive planning to lower negative impacts. It is an excuse for business as usual.

Confusion about offsets and their value in perpetuity are well illustrated by a current example. In 2016 1,001 hectares of land were bought as an offset for the Roe 8 project and will be added to Yalgorup National Park as a newly created A Class reserve.  According to Environment Minister Stephen Dawson this ‘will provide the highest level of protection to western ringtail possum and Carnaby’s cockatoo habitat.’ (
I am absolutely certain that the Minister knows that a government can revoke the protected status of a conservation area and not even compensation would be necessarily required. (Evans and Maron, 2013)
A class reserves are currently in the Busselton area at risk of losing their protected status.
Also, Yalgorup National Park has failed in the longer term as a translocation site for western ringtail possums and any extension to suboptimal habitat (or added protection for it) might not benefit the species significantly.

unregulated relocations