Recommended interim water receptacle treatment for exotic mosquitoes on international foreign fishing vessels arriving in Australia

Abstract

Exotic Aedes mosquito larvae are commonly found in receptacles as equipment or cargo that hold or have held water, on overseas vessels arriving in the Northern Territory (NT) of Australia. This applies especially to international foreign fishing vessels (IFFV) from Indonesia, which are commonly intercepted fishing in Australian waters by the Royal Australian Navy (RAN) and Customs and detained in Darwin or Gove harbours. The drinking water storage receptacles aboard these vessels are often found to contain Aedes aegypti and Aedes albopictus larvae. Drinking water storage receptacles are the most commonly detected type of container to carry exotic mosquito pupae, larvae and eggs into the NT. Aedes species eggs are desiccation resistant and can often be present in either water holding or dry receptacles. The eggs are laid just above the water level on the inner surfaces of receptacles. Approved procedures to treat drinking water receptacles only allow the use of chlorine, due to the residue concerns posed by the use of insecticides. These treatments are part of routine quarantine inspection and control procedures on vessels or aircraft in the 400 m quarantine zone around air and seaports.