The efficacy of crab condos in capturing small crab species and their use in invasive marine species monitoring

摘要

Crab condos are designed to sample for invasive species, which are not specifically targeted using current Australian biosecurity methodologies. Smaller crab species are often excluded, overlooked and damaged to be collected via current trapping or collection methods. An artificial habitat collector such as the ‘crab condo’ (PVC tubes 25cm long and 50mm diameter arranged in a 3×3 square matrix) aims to provide shelter among an animal’s natural environment. Twenty condos were deployed on a weekly basis for 48 hours during the months of April and July 2012 within Hillarys Boat marina, Western Australia. Condos proved to be highly successful, capturing a total of 555 specimens from five different phyla, with over half (n=332) of specimens identified as crabs. The detection of 223 other smaller non-crab individuals, covering four different phyla highlighted the versatility of condos to sample a range of other small species, not only crabs. Given the recognized importance of early detection of marine pests at their early life stages and current lack of methods targeting small and cryptogenic species, the crab condo sampling method may fill an important gap in marine pest surveillance capacity.