Ant community responses to land use change: An investigation of Australian Eucalypt forests

Background/Question/Methods

The diversity, abundance, and functional roles of ants are crucial to native ecosystems. They serve as ecosystem engineers by providing services such as soil turnover, litter decomposition, and seed dispersal. Habitat fragmentation and loss can have deleterious effects on ant communities and may interrupt the availability of certain ecosystem functions. Therefore, understanding how ant species and communities respond to processes associated with habitat fragmentation and loss is important to understanding the impacts of human induced habitat alteration.

This study seeks to broaden the understanding of the impacts of human activities on ecosystems. This will be accomplished by investigating the response of ants to land use change in native Australian eucalypt forests. The questions of primary interest are: 1) Do remnant native forest patches contain different ant communities than continuous native forest? 2) Do ant communities found in patch interiors differ from those found at patch edges? 3) Which ant species reside in the intervening matrix? 4) What metapopulation/metacommunity theories best describe observed patterns?

The Wog Wog long-term habitat fragmentation experiment was established in 1985 when native eucalyptus forest was clear-cut and pine plantations were planted. Within the pine plantation, four replicates of three different sized Eucalyptus patches (0.25 ha, 0.875 ha, 3.062 ha), were maintained and two control replicates were established in adjacent national park. Each patch within a replicate has eight monitoring sites, each with two pitfall traps. The surrounding pine matrix contains an additional 44 monitoring sites bringing the total monitoring site number to 188. The traps are open three times a year, in November, February, and May, for seven consecutive days.

Results/Conclusions

Preliminary assessment of Rhytidoponera sp. indicates this genus has not been affected by fragmentation and habitat loss. Interior/edge spatial analysis of within patch occurrence has not yet been conducted. This genus has been found in every remnant patch and virtually every matrix monitoring site indicating a patchy-population metapopulation scenario. How other ant species at Wog Wog have responded is currently being examined.