Stokes Water Quality Sampling
Water monitoring has been conducted at Stokes Inlet throughout 2020 to establish baseline water quality data on the area that fills historical & geographic gaps in knowledge. Two rounds of sampling have occurred in June and September thus far with another two scheduled in, based on the ANZECC guidelines and following the format from the most recent sampling of the Inlet which occurred in 2010.
Results from our sampling thus far are quite significant. Stokes Inlet is more saline than seawater and has a nitrogen count of nearly double the ANZECC guidelines. This has a direct correlation to nutrient run-off from agricultural activity in the catchment and reflected by high readings of chlorophyll a. Ammonia is over double the ANZECC guidelines and total phosphorus that has fallen from 10x over to 2x over the guidelines, likely from the freshwater inputs over winter. These results are agreeable with the results found in 2010, where nutrients were exceeding ANZECC limits, and demonstrates that the nearby agricultural activity is having a long term, continuous effect on the system.
Past fish kill events have already occurred in the estuary (2007) and with the nutrient levels observed over the last few months, the Inlet could be on track for more. As an important recreational and commercial fishery, management of the system is imperative. At the completion of the final two rounds of sampling, we will be able to formulate a complete snapshot of the system, that will help us to implement management steps that ensure the health of the system, and it’s ongoing ecosystem services.
