The effects of human impacts on Antarctic sponge species in the Ross Sea

Samples were analysed for heavy metals, total nitrogen and phosphorous, hydrocarbons, persistant organic pollutants and tributyltin (TBT). Microbial symbionts are increasingly being identified as the source of many compounds isolated from sponges. The chemical ecology of Antarctic sponges was examined and the within and between site biochemical variation, and the influences of pollution on secondary metabolite production both as an indicator of stress and as a source of novel and potentially valuable chemistry was investigated from these samples.

Glass slides were deployed to examine the relative development of biofilms and recruitment at each site after one year. The total microbial communities were described using cultivation and molecular techniques to analyse population changes with respect to increasing levels of pollution as microbial biofilms can also have a strong influence on the settlement of many reef invertebrates. The key outputs of this research include a series of diagnostic test for measuring sub-lethal stress responses that can provide environmental managers with valuable predictive information, and a library of novel Antarctic microbial symbionts as well as invertebrate extracts for natural product screening programs.