Density of an environmental weed predicts the occurrence of the king brown snake (Pseudechis australis) in central Australia

摘要

The king brown snake (Pseudechis australis) is a large and highly venomous elapid, which occurs throughout much of mainland Australia. Although an ecological generalist, anecdotal evidence suggests that individuals in the arid-zone are more frequently observed in proximity to dense grass cover. We tested the hypothesis that P. australis are more likely to be located close to dense grass cover in an arid region near Alice Springs in the Northern Territory. We focused on the environmental weed buffel grass (Cenchrus ciliaris L.) because this species comprises the highest density of cover in the region. Under an Information- Theoretic framework we used logistic regression to model the occurrence of P. australis against a range of habitat variables expected to influence the snakes distribution and abundance. There was substantial support for our hypothesis with the model including only the variable buffel grass as the best ranked model predicting P. australis presence. The probability of recording P. australis in a location increased with the density of buffel grass cover. Eradicating or reducing buffel grass in and around built-up areas may reduce the risk of interactions between humans or domestic animals and P. australis.