The Australian Wildlife Hospital recently completed a progress report on a ground-breaking koala research project designed to help save the species.  In May 2007 the Australian Wildlife Hospital (AWH), in association with the University of Queensland, commenced a research project sponsored by Gold Coast-based company Zarraffa’s Coffee to investigate the survival and dispersal patterns of rehabilitated juvenile koalas released into rural koala habitat and, in particular, to compare findings between male and female koalas.

Kiersten Jones (UQ), Kenton Campbell and Shae Crawford (Zarraffa’s) release koala “Banana”

More than 2000 sick and injured koalas are rescued and presented to wildlife organisations annually for veterinary attention in southeast Queensland alone, with orphaned koala joeys then requiring hand-raising for up to 15 months.  Although the reintroduction of hand-raised koalas is a relatively common practice, little post-release monitoring had been carried out and reported to be able to confirm the success of this process.

Over twelve months on, the AWH project has demonstrated that the practice of hand-raising koalas is successful, in so far as seven of the 10 koalas in the subject group have survived to this point without human intervention, and two other koalas have survived with the aid of medical treatment.

For the purpose of the research project, the subject group comprised of ten koalas who had never lived independently in the wild —  six females and four males.  Eight had been hand-raised and two had been parent-raised in care.  The koalas’ age on release ranged from 15 months to  two years.

Throughout their first 12 months in the wild all the koalas exhibited normal behaviour in terms of habitat utilisation, tree preference and dispersal and had established home ranges within eight months of their release.  The females settled into home-range patterns of movement closest to the release site, while the male koalas ventured further — the greatest distance travelled was 14 kilometres.  Reproductive success was also high amongst the group, with all but one of the females producing offspring.

Ironbark Station, a 3450-acre rural-conservation property owned by Australia Zoo and found in the Crows Nest Shire in the northeast Darling Downs, was considered the ideal site to investigate the dynamics of the young koalas’ dispersal post-reintroduction by virtue of it providing large and protected habitat, and with the added benefits of the adjacent habitat, an existing koala population, and the ongoing preservation and regeneration of the natural environment.  The young koalas did however have to contend with the risks of feral dog predation, misadventure associated with interaction with cattle, logging practices by local property owners, and the drought conditions that were present for much of 2007.

The release site was also significant because previous studies have mainly concentrated on the survival of koalas in areas of continuing habitat destruction and encroachment of human development.  In urban areas the most common causes of koala mortality are domestic dog attacks, motor vehicle incidents and disease.  The selection of a rural setting for this tracking project therefore vastly reduced the likelihood of the two man-made elements becoming an impediment to the koalas’ chances of survival.

Under the supervision of Dr Jon Hanger, Director of Veterinary Services and Research at the Australian Wildlife Hospital, Kiersten Jones — an Applied Science honours student from the University of Queensland — monitored the movements of the 10 koalas who were fitted with collars designed to emit a unique tracking frequency.

Following their release, the koalas were tracked daily for three weeks, and then every two to three days. During times of long-distance dispersal, daily tracking occurred.

As part of the year-long monitoring, the koalas also underwent comprehensive health checks conducted by the AWH veterinary team — occurring on release, after six months and again after 12 months in the wild.

These health checks confirmed suspicions that the subject group would not be immune from the ravages of disease that are so prevalent amongst koala populations Australia-wide.  Three koalas required medical intervention during the twelve month period:  one of the males contracted chlamydiosis, including associated prostatitis and was admitted to the AWH for a two-week treatment of antibiotics, while a female koala developed reproductive cysts resulting in infertility. She underwent successful surgery, allowing her to also re-join the subject group. Sadly, another female was diagnosed with lymphoma, a fatal cancer of lymphoid tissue, in the project’s eleventh month, resulting in euthanasia.  This was a major blow to all involved with the project.

“Statistics collected by the Australian Wildlife Hospital over the past four years have validated suspicions that disease is at epidemic proportions in the koala population, with serious consequences for the survival of the species”, says Dr Hanger.

The project team has aspirations for the detailed research findings to influence future koala conservation efforts, particularly in Queensland where koala numbers continue to decrease at an alarming rate. Identifying and assessing remaining areas of protected habitat is the key to on-going research and, at the same time, acknowledging the need to replace outdated koala-management practises as a result of the changing physical landscape – specifically, recognising that koala habitat in southeast Queensland is becoming increasingly reduced and fragmented.

Australian Wildlife Hospital Manager Gail Gipp said koalas in southeast Queensland are classified as vulnerable under the State-Government legislation and a concerted effort is needed at both government and community levels if we are to have any hope of arresting the decline in koala numbers.

“Right now eco-factors which should be occurring naturally, such as genetic mixing, are becoming obliterated, leaving lots of ‘islands’ of koala populations that have very little chance of surviving the next two decades without intervention.”

The Australian Wildlife Hospital team is grateful to Zarraffa’s Coffee, whose financial contribution enabled the project to come to fruition and, in particular, the personal involvement of Zarraffa’s CEO Kenton Campbell who took part in the field work on several occasions.

Mr Campbell learned of the Hospital’s ambitions to initiate the project through his company’s close alignment with Australia Zoo Wildlife Warriors Worldwide and was very eager to have a hands-on involvement and offer any support he could.  Zarraffa’s Coffee subsequently enlisted the support of its franchisees and their local communities to raise awareness and almost $25,000 to purchase equipment needed for the project through donations and in-store fundraisers.

“I’ve always been very passionate when it comes to conservation matters, and I find it alarming that one of Australia’s most iconic animals is classified as “vulnerable” to extinction.  Having the opportunity to assist with the koala tracking project has meant a lot to us, because we have helped to fill a void in terms of what is known about koala behaviour. We hope that the information gathered will bring us a step closer to ensuring these native treasures are around forever,” Mr Campbell said.

The monitoring is being extended into a second year and the project team hopes that the additional research gathered will further spotlight the challenges for koalas in the wild and prompt this generation to take the actions necessary to save them and, even ourselves, for the loss of koala habitat reflects a breakdown in ecosystems upon which people too are reliant.