The Finniss Catchment Group has been monitoring water quality and observing macro-invertebrates at seven sites around our catchment since 2004. We are part of the Waterwatch Community Monitoring program.  Ours is not the only data available about our catchment as there are individuals, school groups and environment groups doing the same - some for longer than us. We measure salinity, pH, nitrates and phosphates, turbidity and temperature. Usually its the salinity that we are most worried about but we do have one site that often has high nitrates or phosphates probably from excess local use of fertilisers. We also take note of water quantity and the general condition of the site. We chose our sites at the beginning by looking for what we thought were permanent water holes with reasonable access available. However since then some of our sites have dried up for some of the year because of the excess use of groundwater in the local area.A good indicator of the health of a site is a check of what is alive in the water. An invertebrate is a being without a backbone (they are 97% of all species). At our sites we look for aquatic macro-invertebrates. They are small animals that live for all, or part of, their lives in water and are large enough to be seen without a microscope. The biggest we see are yabbies and the smallest are sponges and water mites. We dab about with a net and take samples, then identify the species and count the number of species present. Some species are rarely found in polluted water, others seem to be able to mange quite nasty conditions; so scientists have put together a scale where we assign a value to each species that we have identified and we end up with a number that tells us how healthy our sites are. Some of our data is available on the Waterwatch site where our seven sites have the codes MEA-200, FIN-550, FIN-200, FIN-009, FIN-010, BUL-300 and BUL-400. |