Koalas are getting special treatment in a Queensland residential area in an attempt to study how koalas and humans can both share the same space comfortably, and how residential developments can also protect biodiversity.
Maren Dammann is studying the movement patterns of koalas in ‘Coomera Waters’, a new housing estate in South East Queensland, containing patches of native vegetation and high numbers of koalas. She aims to learn how green developments can be made more appealing to the native marsupial.
Ms Damman is in her last semester of a Master of Science (Conservation Biology) degree at UQ. Her study is the first to focus on movement patterns of koalas in ‘green’ developments, working with the developer to learn about the species and to find out what makes the koalas happy to remain in the area. It is designed to learn about habitat use and what a development design should look like in order to sustain koalas over a longer term.
‘Coomera Waters’, 40km south of Brisbane, was developed by Austcorp. The company sponsors Ms Damman’s research and hopes to use her findings in other residential developments. Austcorp has applied some green principles at ‘Coomera Waters’, such as including extensive parklands and reserves with large amounts of native vegetation. Corridors connect the patches, and koala food trees are planted along the streets. Butterfly-friendly plants have been planted in some parks, and residents are advised about which plants they should grow to attract wildlife, especially birds.
Her study has four direct purposes: (1) to examine the distribution and abundance of koalas in the development area, (2) to observe and analyse their movement patterns (3) to examine their habitat use and preferences in tree species and (4) to examine the attitudes of residents towards koala related issues.
“One aim of the project is to find out which characteristics of parks/corridors correlate with koala presence,” she said. “The development is still in an early phase, so changes in abundance, behaviour and habitat use of koalas can be observed.
“The findings of this study will contribute to greater knowledge about koala habitat and how to enhance the species’ survival in areas of residential development. Austcorp is very interested in our results and outcomes and wants to use them for further development projects.”
To start with, 12 koalas were caught and assessed for weight, body condition, tooth wear, gender, head length, and head width, and (for females) reproductive status. Tooth wear and weight were used to estimate age, and the animals were assigned to one of four age classes. Class one are pouch and back young, class two recently weaned animals, class three young independent adults and class four adults. Only animals from classes one and four were found in the sample.
Body condition was measured using haptic assessment of the anterior and posterior muscles associated with the scapular ridge. Two assessors determined body condition on a scale from 1 to 10 (very thin and sick to perfect healthy condition). Ms Damman said the animals were not anaesthesised for the assessment and each koala was handled for only 45 minutes. “The welfare of the animals was considered during the entire handling procedure.”
Eleven animals (seven females, four males) were fitted with GPS data-logging collars; two of the collared animals had back young. The twelfth, a male, was fitted with a VHF collar. After a few months, the animals were caught again, the collars removed and the data downloaded.
During the data collection period, the animals were radio-tracked from time to time to observe if the collars were still on, if the animals were alright, and to get an indication of tree usage preferences during the day. “This data gives us an indication of the size and shape of the home ranges of the koalas and their movements through bush patches and the broader urban landscape,” she said.
Line-transect sampling was also conducted to estimate the koala density within the development area. A questionnaire is being prepared for distribution to the development residents. The objective is to learn about the residents’ attitudes, level of interest in koala conservation issues and to find out about local environmental factors that affect koalas.
Maren Dammann with a baby baby koala
Community involvement is very important in protecting the koala habitat, Ms Dammann said. “Community involvement plays a great role for us, and the research project integrates the public. Through a local newsletter, residents of ‘Coomera Waters’ were invited to participate and report sightings of koalas to us. Every koala has differently coloured ear tags, which makes them easy to recognise for residents (and us).
“We hope that an active involvement of the residents leads to a positive attitude and appreciation towards the species, our research and the natural environment in general. That is very important for koala conservation because residents can assist the species through their own actions, such as restraining their dogs and planting native vegetation.”
So far, the ‘Coomera Waters’ residents have demonstrated a high level of interest in the project and provided useful information about koala sightings and abundance. “People are very friendly and communicative. For example, when we caught a koala from a front yard, the owners watched and wanted to learn about koalas, especially their young daughter Ashleigh. On the next day, Ashleigh took the photos of ‘her’ koala to school to report about the species.”
Ms Dammann has completed her fieldwork, and is now working through the data analysis, under the supervision of Dr Sean FitzGibbon and Dr Robbie Wilson. Her project is part of a larger project to assess the effectiveness of green developments in SE Queensland at conserving native wildlife. “Many developers claim to be ‘green’ but we don’t really know if their development designs and approaches are actually good at saving wildlife,” she said.
Several UQ researchers are involved in this broader study examining about 30 green developments. Her supervisor, Dr Sean FitzGibbon and Ben Barth are focusing on the diversity and abundance of birds, dung beetles and microbats.
Â©Sue Cartledge 2009