title: The Ecological Value of Suburban Golf Courses in South-East Queensland
Creators: name: Hodgkison, Simon Charles
Publisher: name: Griffith University
Year: 2006
Subjects: subject: Golf course ecology
subject: species refuge value of golf courses
subject: urban environments

description: Information is required on the ecological value of all urban land types in order to provide an ecological basis for urban zoning decisions, to predict development impacts and to identify much needed opportunities for off-reserve conservation. One land type (the suburban golf course) has experienced a dramatic global proliferation in recent decades, as courses are increasingly constructed as part of new housing developments and resorts. Golf courses account for a growing proportion of the urban land area in Australia and will have an increasingly significant impact on urban biodiversity. The nature of their influence is however contentious. While many suggest golf courses have a negative impact on biodiversity, others believe they can provide refugial habitat for native wildlife. This potential refuge value has been nurtured by the golf industry as a way to improve its environmental reputation. However while the industry has initiated programs to enhance the quality of habitats on golf courses, it is uncertain whether such small-scale conservation efforts can have more than a cosmetic effect. The ubiquity of suburban golf courses makes their possible ecological contribution more significant and thus worthy of investigation. This study assessed the conservation status of suburban golf courses in south-east Queensland Australia between 2001-2004, by comparing assemblages of birds, reptiles, mammals and amphibians on 20 representative golf courses with those in 10 nearby eucalypt remnants and with bird assemblages in 10 suburban areas. The ecological characteristics of wildlife utilising golf courses were compared with those shared by animals common to residential areas and to native eucalypt forest. Local changes in bird diversity were assessed following the clearance of small vegetation remnants on a suburban golf course. Finally, the ecological value gained by increasing the size and complexity of native habitats on golf courses was assessed, by investigating the extent to which differences in biodiversity among golf courses were attributed to the size, shape and complexity of local, landscape and regional habitats on and adjacent to golf courses. Golf courses displayed extreme variation in conservation value. While a number of golf courses had significant refuge value, supporting high densities of regionally threatened vertebrates, most supported only common urban-adapted species and therefore failed to realise that potential. Wildlife assemblages in residential areas and on most golf courses were more homogenised than those in eucalypt forests and were generally dominated by species with broad ecological tolerances. In contrast, ecological specialists were restricted to eucalypt forests and a minority of golf courses. The clearance of even small remnants of native vegetation on a single golf course had a significant homogenising effect on local bird assemblages with a diverse range of regionally threatened birds being replaced by a small number of urban-adapted species. Golf courses that did have refuge value had the capacity to accommodate most regionally threatened species. In general, golf courses were a better refuge for threatened birds and mammals than for threatened reptiles and amphibians. The relative absence of threatened herpetofauna may reflect heightened sensitivity to habitat isolation, faster rates of local decline, to increased local threats (i.e. predation or herbicide exposure) or a difference in the extent to which their habitats have been compromised. Differences in biodiversity among golf courses were attributed to environmental factors acting at local, landscape and regional scales. While the local diversity of all vertebrates was partly determined (and therefore restricted by) regional influences, the local abundance and species richness of threatened vertebrates still closely reflected the size and structural complexity of on-course habitats. The diversity of all vertebrates increased with the area of native vegetation retained locally. Species-area curves were observed among reptiles, birds and mammals. Contrary to other studies, there was no distinct threshold in the species-area relationship. Threatened species gradually disappeared from the landscape as patch sizes decreased below 5ha. The lack of any distinct threshold highlights the dangers of proposing spatially explicit guidelines to ecologically sound development. Patches should always be as large as possible if they are intended to provide refuge to threatened vertebrates. Remnant size was however, co-correlated with structural complexity, with the understorey of smaller remnants often cleared to increase course playability. Biodiversity in small remnants (less than 5ha) may therefore be increased by enhancing the structural complexity of local habitats. Bird diversity increased with foliage height diversity and native grass cover. Mammal diversity increased with tree density, native grass cover and the abundance of hollows. Reptile diversity increased with the abundance of woody debris and declined with the proportion of turfgrass cover. The diversity of amphibians increased with waterbody diversity, the complexity of aquatic and riparian vegetation, the number of connecting streams and declined with the steepness and proportion of turfgrass cover on waterbody banks. Golf courses can evidently provide locally valuable refuges for threatened vertebrates and have a clear opportunity to make an important localised contribution to urban wildlife conservation in SEQ. The extent to which this potential is realised will however depend on the extent to which ecological criteria are incorporated into golf course design and management practices. The current low conservation status of most existing golf courses reflects a historic lack of regulation and formal Environmental Impact Assessment within the golf industry. This has seen few golf courses retain any substantial area of complex core vegetation. While the industry is aware of its conservation potential, the economic pressures affecting modern course designs will tend to restrict the area of native vegetation that can be retained (particularly among housing development courses where there is pressure to maximise the area of land available for housing). Legislation recognising and protecting the value of small remnants in new golf developments may be required if the golf industry is to realise its conservation potential.