Attributes of rock-dwelling reptiles within the Australian wheat-sheep zone

Rocky environments host rich levels of biodiversity, and provide vital
habitat for specialised organisms, range-restricted species, and a broad
range of ectotherms adapted to saxicoline environments. In Australia, rock
habitat is being destroyed during soil amelioration practices associated
with agricultural intensification. Advances in rock crushing technology,
developed to expand or increase crop yields and efficiency, pose an
undocumented threat to biodiversity, especially reptiles dependent on
non-renewable rock habitat in agricultural landscapes worldwide. Rock
removal is a legislated key threatening process in parts of Australia and
will accelerate biodiversity loss if not mitigated. We estimated reptile
species’ range overlap with dryland cropping and modified pastoral regions
within the Australian wheat-sheep zone to assess potential impacts of rock
crushing practices. We examined species- and family-richness within the
impact zone, and across bioregions within the impact zone, to identify
areas where rock removal has the greatest potential to impact terrestrial
and fossorial squamates.   Our analysis revealed that 159
potentially impacted reptile species occur within the study area,
representing 16% of Australian terrestrial squamates. Fourteen of these
species, including six threatened species, have more than 50% range
overlap with areas of intensive agriculture, and include several
endangered pygopodids, scincids and agamids.   Bioregions rich in
rock and burrow-dwelling reptiles include the Brigalow Belt South,
Murray-Darling Depression, Darling Riverina Plains, Eyre York Block, Avon
Wheatbelt, Nandewar, Flinders Lofty Block and New South Wales South
Western Slopes. Synthesis and applications. The conservation of reptiles
in agricultural landscapes requires appropriate management and retention
of surface rocks. Potential yield increases from destroying rock habitat
to intensify or expand cropland will not compensate for the net loss of
reptile populations dependent on non-renewable resources. Financial
incentives to prevent the expansion and transformation of non-arable
landscapes to cropland is required to prevent ongoing loss of
biodiversity.