Understanding oxygen dynamics and the importance for benthic recovery in Macquarie Harbour - Progress Report

This report provides an update on the status of dissolved oxygen (DO) and benthic conditions in Macquarie Harbour. It follows on from the results outlined in the IMAS reports released in January, May, September 2017 and January and June 2018. These reports described a deterioration of benthic and water column conditions in Macquarie Harbour in spring 2016, early signs of faunal recovery observed in May 2017 and a subsequent decline in benthic conditions in spring 2017 when oxygen concentrations in middle and bottom waters returned to very low levels. In the June 2018 report we highlighted that oxygen concentrations in the middle and bottom waters improved through the summer of 2017/18 due to recharge events that commenced in late spring 2017. This report presents the results and preliminary interpretation of a repeat survey of benthic communities in June 2018 and DO monitoring data up until the beginning of October 2018. This work is part of the research project (FRDC Project 2016-067: Understanding oxygen dynamics and the importance for benthic recovery in Macquarie Harbour to address these needs) funded by the Fisheries Research Development Corporation with the support of both industry and government (EPA and DPIPWE).