Brisbane is Australia's most biodiverse capital city, but lies at the heart of a rapidly urbanising region. One of the challenges facing the region is how its biodiversity can be maintained and managed in the face of ongoing land-use change. To do so, we need to build a better understanding of relationships between wildlife and land-use, and monitor their changes over time.
Project Outline
Birds are an important component of regional biodiversity. They are rich in species, diverse in ecological function, important in ecosystems, and important to people. Birds are also easily surveyed, making them an ideal group for monitoring and developing indicators of environmental change.
In 2006 Griffith University and Brisbane City Council entered into a four year Biodiversity Research Partnership with the goals of assessing recent changes in Brisbane's birds, and developing useful indicators for assessing the quality of their habitats. Since then, the partnership has grown to include James Cook University, Logan City Council, and SEQ Catchments.
The project includes re-surveys of a large number of sites in the Brisbane region where birds had been surveyed in the early 1990s, including suburbs and bushland remnants of various sizes. This will allow us to quantify changes in bird composition over the last 15 years, and to compare the extent of change between intact bushland, fragmented bushland, and urbanised areas. Are noisy miners and crows becoming more widespread and abundant? How are forest-dependent birds faring in bushland remnants surrounded by suburbia? Are introduced species increasing in the Brisbane region? These are the kind of questions being answered by this project.
Current Results and Outcomes
In 2006 we re-surveyed the birds of 54 sites. While we cannot draw any firm conclusions until further sites have been surveyed, a preliminary look at the data shows some interesting trends. Many species have shown increases in the suburbs over the last 15 years. For example, the noisy miner occurred at 88% of suburban sites in 2006 compared with 50% in the early 1990s, and crows were recorded at 81% of sites in 2006 compared with 35% in the early 1990s. However, other species in the suburbs have declined, such as the house sparrow and kookaburra. Bushland sites appear to have been more stable, with most species showing less change over time. During 2007 we will be re-surveying a further 70 sites.
Future Partnership Outcomes
Once we have data from a larger number of sites we will be able to conduct statistical analyses of changes in the number and types of bird species. For example, we will look more closely at trends within the bushland areas. Other work will focus on how changes in habitat elements such as cover of vegetation and built structures may lead to changes in the bird community, at both local and landscape scales. This will help forecast the effects of various management options on bird diversity, providing information which will be of great value for land-use planning and biodiversity management.
- Birds in an urban landscape project factsheet (PDF 470k)
- Please contact Associate Professor Carla Catterall for more information.