Habitats of the Striated Grasswren Amytornis striatus rowleyi at Opalton, central western Queensland

Abstract

Habitat of the Striated Grasswren Amytornis striatus rowleyi (Rusty Grasswren A. rowleyi) was examined at 51 sites with spinifex Triodia spp. at Opalton in central western Queensland during 14 visits between May 2009 and October 2012. At both small (radius 30 m) and large (radius 100 m) spatial scales, Striated Grasswrens occupied mostly Normanton Box Eucalyptus normantonensis low open woodland on spinifex-covered flat or gently sloped terrain with sandy soil covered by brown or reddish-brown lateritic gravel. This habitat comprised 55–57% of all habitats used at both sampling scales. The Grasswrens occurred less frequently in other spinifex-covered low open woodland or low open forest sites dominated by Mountain Yapunyah E. thozetiana, Lancewood Acacia shirleyi, Mulga A. aneura or Gidgee A. cambagei. A sparse shrub layer of Witchetty Bush A. kempeana or cassia Senna spp. was present in ~50% of sites sampled at the larger scale. Six sites on low caprock mesas were characterised by a relatively high density of Witchetty Bush shrubs (maximum cover 15%) and a relatively low cover of spinifex (14.8%) under a sparse tree layer of Mountain Yapunyah or Lancewood. The overall average height of spinifex hummocks (excluding seeding stalks) was 37.5 cm, and the average cover of spinifex was 26.3%.