Port of Karumba
Long-term seagrass monitoring
Progress report. October 2003.

Michael Rasheed, Ross Thomas and David Foster
Queensland Department of Primary Industries and Fisheries, Cairns.

In October 2003 seagrass area and density (biomass) in Karumba had begun to recover from the record low levels that occurred in the previous year (October 2002). Cover of seagrasses was more consistent in 2003 leading to a substantial increase in area for the core monitoring meadow. Biomass of the core meadow however was still very low and remained significantly lower than values recorded prior to 2002.

Karumba seagrass meadows had a store of seeds in the sediments (seed bank) from which recovery could occur in the event of disturbance to the meadow. There was evidence that some of the recovery observed in the meadow in 2003 was due to the germination of some of these seed resources. The most likely driver of seagrass changes observed in Karumba remains atypical climate conditions rather than human activities conducted in the port. While recovery of the meadows had begun to occur in this survey, the seagrasses remain vulnerable to new disturbances or adverse conditions due to the continuing low density (biomass) of plants. In the absence of further disturbances and a return to more typical regional climate conditions we would expect the recovery of Karumba?s seagrass meadows to continue. Seed sampling and measurements of temperature and other environmental variables in the seagrass meadows will continue in future surveys enhancing interpretation of seagrass changes.

For a full copy of this report contact QDPI&F on 07 4035 0112 or michael.rasheed@dpi.qld.gov.au