Native Grazers: friend or foe of native plant species?

Developer 2 (MM) - Wednesday, August 13, 2014

Most of us are aware of the impact that grazing and trampling by stock and rabbits can have on plant communities across the arid zone. However, little is known about the effects of native grazing animals, particularly medium sized mammals which are now largely extinct across most of arid Australia.

The Arid Recovery Reserve is home to a number of these mammals, including burrowing bettongs, bilbies, bandicoots and stick-nest rats. While establishing populations of reintroduced species within the Reserve has been very successful, we also need to know what effect these animals are having on our plant species.

Since 1997, a number of monitoring sites have been established by Arid Recovery, in collaboration with DEWNR’s Pastoral Branch. Arid Recovery has been monitoring plant cover, condition, diversity and recruitment to determine the effects of introduced herbivores (i.e. rabbits) and reintroduced herbivores (i.e. our bettongs, bilbies, bandicoots and stick-nest rats) on native vegetation communities within the arid zone, and to determine the strongest indicators of change.

Arid Recovery was recently awarded a grant from the South Australian Native Vegetation Council to analyse the data collected as part of the vegetation monitoring, which provided the opportunity to examine hypotheses based on what sorts of changes we expect to see at a landscape scale. A number of researchers at Arid Recovery have also carried out specific studies to investigate whether native herbivores actually provide a benefit to the arid ecosystem, rather than the devastating impacts of introduced herbivores such as rabbits.

The changes in vegetation that we would expect to see include a reduced impact of native browsers on plant recruitment compared to that of introduced species, with higher survival and growth rates of seedlings in areas where rabbits and livestock are excluded. The level of impact, however, is likely to vary depending on the density of individuals within an area.

One Arid Recovery study showed that low to moderate densities of bilbies, bettongs and stick-nest rats have a significantly lower impact on shrub recruitment than low densities of introduced cattle and rabbits.  Recruitment of common species such as mulga, silver cassia and sandhill wattle was reduced or arrested by even low densities of cattle and/or rabbits.  Evidence from this study suggested that mulga may suffer regional declines if recruitment continues to be suppressed by rabbit and cattle browsing. Another study conducted at Arid Recovery has shown that foraging pits dug by bilbies and bettongs may facilitate seedling recruitment. Bilby digs can trap moisture and minerals, creating nutrient rich soil.

A bilby dig at the AR Reserve, showing how it collects seeds, grasses and plant matter, increasing nutrients in the soil at that point.

Arid Recovery is continuing to monitor vegetation changes in response to the presence of introduced and native herbivores. Continuing analysis of the monitoring data should allow us to determine the most effective indicators of change, not just within Arid Recovery but on a landscape scale. Our research will highlight the importance of establishing indicators of overstocking of native species in fenced areas like Arid Recovery, may also assist with developing novel revegetation strategies such as changing the habitat for direct seeding by mimicking animal digs.

How to become a scientist

Developer 2 (MM) - Wednesday, August 13, 2014

The Arid Recovery Reserve is buzzing with the launch of a new bettong behavioural study- and you can be involved!  There is a scientist within us all and we would like to give all our volunteers, members, tourists and school children a chance to be involved in the science we undertake.

Anyone lucky enough to have been out to the reserve and had the chance to see our threatened Burrowing Bettong will know they are quite social creatures.  We at Arid Recovery want to find out more about the interactions between Burrowing Bettongs and what it all means and this is where you come in. 

As part of the project a number of individuals will be marked with coloured ear tags so that tourists and others visiting the reserve in the late evening will be able to identify individuals and how they interact with one another.  Burrowing Bettongs will also be radio collared, offering educational groups to the reserve the unique opportunity to radio track a real animal, finding out where they hide during the day and who they are living with.

“This project is going to provide everyone, particularly the local community, with a fantastic opportunity to be involved in science.  Hopefully it might get people asking a few more questions about the world around them and increase their involvement,” quotes Hannah Spronk, Volunteer and Community Coordinator.

The project has been kick started with some generous funding through the Optus Regional Community Grants.  “Thanks to the Optus Regional Community Grants we will be able to start this project off on the right foot,” agrees Hannah.

For more information on the Burrowing Bettong Behavioural Project or to find out how you can be involved contact the office on (08) 8671 8282 or email volunteer@aridrecovery.org.au

BHPB Matched Giving Support, where does it go?

Developer 2 (MM) - Wednesday, August 13, 2014
BHP Billiton's Matched Giving Program contributes $10 per hour of volunteer work undertaken by BHPB employees towards the cause of their choice, and also dollar for dollar on many donations given by their employees.  The value of monies raised this quarter by Arid Recovery volunteers through the BHP Billiton's matched giving program is priceless.

This Autumn quarter will have a 'feral focus'.  Funds raised via the Program will help with maintenance of our existing remote monitoring system and feral eradication of the Red Lake Expansion.  March, April and May are the 'golden months' for feral predators as young cats and foxes begin to emerge. Hence it is a crucial time to maintain our feral control programs and monitoring to enhance our knowledge of these amazing but devastating feral predators.

Arid Recovery would like to give special thanks to all the volunteers who have given their time to assist our cause this past quarter, in particular those that assisted with annual trapping, and in this quarter we highlight those involved with feral animal control.

Arid Recovery Awarded NRM Community Grant

Developer 2 (MM) - Wednesday, August 13, 2014
Minister for Environment and Conservation, the Hon. Jay Weatherill MP announced Arid Recovery among the successful applicants of this highly competitive grant.  The $50,000 received will enable Arid Recovery to improve monitoring of reintroduced species such as greater bilbies and burrowing bettongs, and improve the genetic management of species such as the western barred bandicoot.  Community training sessions in areas such as feral animal control and threatened species monitoring has also been funded, as well as disseminating a decade's worth of arid zone research to various stakeholders in the form of information packs.  Community involvement plays a crucial role in successfully restoring Australia's arid zone. 

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Arid recovery is a conservation initiative supported by:
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