Northern Gulf Resource Management Group

Assessing the impact of floods on biodiversity

Ten million hectares under water for a month is bound to have an impact on biodiversity. After the wet season of 2009 when some 95,000 km2 of the lower Gulf of Carpentaria catchments experienced significant flooding for several months, Northern Gulf Resource Management Group commissioned a rapid biodiversity study. It produced some interesting results:

  • Species present in 37 sites surveyed were nearly all tree-dwellers, although few in numbers.
  • None of the expected common ground-dwelling lizards (skinks, geckoes and dragons) were found on most sites which had been flooded for extended periods.

The results showed that floods appear to have killed most of the ground-dwelling fauna. Only fauna which can survive in trees survived. Ground-dwelling fauna, even if they can climb, are unable to survive for any length of time as they starve or get eaten. They are particularly vulnerable to predation because they have no skill at surviving in trees.