Institution: | a School of Biological Sciences A08, University of Sydney, Sydney, NSW 2006, Australia b School of Biological Sciences, University of New South Wales, Sydney, NSW 2052, Australia c NSW Fisheries Research Institute, P.O. Box 21, Cronulla, NSW 2230, Australia |
Abstract: | Point-source impacts such as sewage plumes can cause significant degradation of larval habitat. Data on larval abundance, current speed and the shape of surface and subsurface sewage plumes off the coast of Sydney, Australia, indicated that long-shore currents can transport large numbers of larvae through plumes that can potentially affect the health of larvae. Deformities to the notochord, eyes and head were found in samples of preserved wild larvae. Some deformities (e.g. Lateral curl of the notochord) were probably caused by preservation and ‘packing effects’ (shaped by organisms and objects in the sample), while others (e.g. half-pigmented eyes and corrugated notochord) were unlikely to have been caused by sampling artefacts. Deformed larvae were found in waters around Sydney that are influenced by multiple sewage outfalls, and at locations up to 250 km from Sydney. It was concluded that deformities were caused by natural and potentially anthropogenic factors. Cyto- and histopathological studies of larvae are required. Moreover, relationships between oceanography and concentrations of pollutants in plumes are needed to further assess impacts of pollutants on assemblages of vulnerable planktonic animals. |