Tidbinbilla Nature Reserve, where I hung out for an incredible week in the mid-semester break, is playing an integral role in reintroducing the Eastern bettong (Bettongia gaimardi) back onto the Australian mainland through its breeding program for the species.
The species was exiled from the Australian mainland in the early 1900’s due to a combination of the usual pressures brought by European settlement. Fortunately, Tasmania has been an oasis for the species where it remains common, however the recent advent of the European Red Fox (Vulpes vulpes) onto the island is a significant threat given Tassie’s geographic isolation.
Testament to the devotion of all staff involved, success in the breeding program has led to robust populations of Eastern (aka Tasmanian) bettongs at Tidbinbilla and Mulligan’s Flat Woodland Sanctuary, the result of a momentous journey that originated with the translocation of six wild individuals from Tasmania in 2011.
The next step for Tidbinbilla’s Bettong breeding program is to establish a free-ranging population with less active management. My project involved using a GPS tracker (to be followed by ArcGIS analysis) to map the locations of suitable Bettong habitat inside the 30acre woodland where the new population will call home. The findings of the mapping will enable staff to focus camera monitoring in areas with maximum likelihood of bettong presence.
Research into the ecology of the species helped me to adopt a bettong mentality by thinking about how they interact with their environment; basically I just combed the landscape pretending to be Bettong, which was good fun.
‘Bettong Bel-Air’ habitat features I searched for included ground story complexity through mature tussock grasses and logs amongst which to build their woven grass nests, over and mid-story coverage to conceal from aerial predators and foraging opportunities offered by patchy ground cover in conjunction with Eucalyptus or Acacia trees where fruiting fungal bodies (a staple of the bettong diet) are often well established.
I was lucky enough to attend the fine-tuned operation of a trapping night with three of the Tidbinbilla wildlife team; Leith, Kym and Lindsay. We identified all Bettong individuals by microchip, weighed, checked pouches of females, measured scrotal diameters of males and checked their general condition.
We also trapped a female Southern brush-tailed Rock wallaby who had a pouch young about 10cm long. It was pretty amazing, recognizing how with such critically low population numbers, this individual is a vital part of the species future. This little critter will be flown in a humidi-crib to Adelaide to be mothered by a surrogate Yellow-footed Rock-wallaby as part of the cross-fostering technique helping to rescue this critically endangered species.
It was cool to see how the scientific principles of conservation breeding programs pervaded everyday management decisions regarding each individual animal. Particularly ensuring maximum genetic diversity and the need for an intimate knowledge of the species biology and ecology.
While interventions for species whose futures hang in the balance can have great outcomes, as the success of the bettong program shows, breeding programs cannot be seen as a fallback that prevents us tackling the pressures on their habitats at the source. For conserving one element of biodiversity is problematic if the ecological community they belong to is not also conserved and protected. Furthermore such programs are costly (resulting in triaging) and are too risky to rely upon, as some species cannot thrive in a captive breeding environment such as the Northern-hairy nosed wombat.
Conserving intact ecosystems with all their parts, including bettong ‘ecosystem engineers’ is a far superior option than trying to piece an ecosystem back together again, as these systems are likely far more complex and fine-tuned than us mere humans can grasp.
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