Ground-dwelling reptile assemblages in selectively harvested dry sclerophyll forest in south-east Queensland

Abstract

Reptile assemblages were examined retrospectively in relation to five age categories of regrowth since the last selective tree harvest (i.e., 0-10 years, 11-20 years, 21-40 years, 41-50 years and >50 years/ virgin). The aim was to identify indicator species that showed consistent response to post-harvest forest regrowth. A total of 47 reptile species were recorded from 95 systematically surveyed sites. Species richness was lower in 11-20 years old regrowth with no effect observed in regrowth aged 40-50 years. This trend was not significant. Reptiles overall, and a subset of 'common' reptiles, were significantly less abundant in 11-20 year regrowth compared to the 0-10 years regrowth. Abundance of reptiles was not significantly higher in older forests (i.e., 41-50 years since harvest and >50 years or virgin sites) than in forests within the 11-40 years since harvest period. The trends in abundance observed amongst all reptiles and common reptiles were largely due to the numbers of skinks. In general, skink abundance was significantly lower in the 11-20 years since harvest period and highest in the first ten years after harvesting. A majority of these skinks belonged to a guild of bark-, log-and rock-dwellers. High shrub density in the 11-20 year old regrowth provides some explanation for lower numbers of skinks recorded. Shrub density may affect the availability of basking sites for reptiles at ground level and the accessibility and searching behaviour of observers. Ambient temperature at the time of survey had a significant effect on the abundance of some skink species, which meant that an explanation was confounded. The common "bark-, log-and rock-dwelling" skinks, Lampropholis spp. and Carlia spp. demonstrated measurable changes to measurable habitat conditions and disturbances, which are traits of model "indicator" species. The limitations of using common skinks as indicator species are acknowledged and a caution is issued in respect to inappropriate use of the species indicator tool.

Factors Affecting the Use of Reforested Sites by Reptiles in Cleared Rainforest Landscapes in Tropical and Subtropical Australia

“…Ideally, a monitoring program would target reptiles that are both sensitive to habitat change and cost effective to survey (see Read 2002 and Goodall et al 2004, for Australian reptile examples). In the tropics, the skink G. queenslandiae meets both criteria because it is strongly associated with large rotting logs, one of the habitat features of rainforest, and it is easy to locate and identify when present (this study; Sumner et al 1999).…”