Birds on the edge: Spatial and temporal patterns in the bird community recorded at a conservation reserve on a bioregion woodland−grassland boundary in central Queensland

Abstract

Monitoring the changes in occurrence and abundance of wildlife communities over time is important for more effective and targeted management and understanding long-term changes due to local and global environmental influences. In this study, we report on the first systematic bird survey carried out on Edgbaston Reserve, a protected area on the boundary of tropical and semi-arid bioregions in north-central Queensland. We systematically sampled the bird fauna at 24 sites over five surveys between 2018 and 2020, using a combination of 2-ha area searches and timed nocturnal censuses. We examined variation in composition and species abundance across the surveys using multivariate, regression and non-parametric analyses. A total of 6201 bird records comprising 123 species was collected. Forty-six species exhibited significant variation in abundance across the six sampled habitat types (Ironbark, Gidgee and Escarpment woodlands, Springs, Spinifex grasslands and Mitchell Grass Downs). Species composition also varied significantly across habitats and surveys, and there were clear differences in the Spinifex and Mitchell grass bird communities compared with those in the woodlands. Twenty species were recorded in only one of the five surveys, and 17 species were recorded in significantly higher abundance in some survey years, associated with an influx of granivores and nomadic and migratory species. The location of the property on the boundary of woodlands and more arid grasslands that contain springs, and the contrasting mix of eastern- and western-distributed birds, suggests that the continued monitoring of the avifauna provides an important opportunity to investigate long-term trends, linked to environmental change and annual management, to assist the preservation of this important bird community situated on the edge of two bioregions.