The Central Bay had a drop in report card grade from a “C” in 2008 to “D” in 2009.  The main reason for this was a reduction in the depth range of seagrass (Zostera muelleri) growing near Victoria Point, which severely impacted the BHR for the zone.  Associated with this was a small increase in turbidity and therefore reduction in light penetration to deeper depths.  As in previous years, the toxic cyanobacteria Lyngbya majuscula remained essentially absent from the Central Bay zone.

Abbreviations glossary

A description of the indicators and methods used can be downloaded as a PDF file.

ECOSYSTEM HEALTH INDEX (EHI)

The EHI is a measure of the proportion of a reporting zone that complied with the water quality objectives for key indicators monitored as part of the Ecosystem Health Monitoring Program. The water quality objectives are defined in the South East Queensland Regional Water Quality Management Strategy (2001).

• EHI 1 = 100% of area complies with the environmental objectives.
• EHI 0 = 0% of the area complies with the environmental objectives.

BIOLOGICAL HEALTH RATING (BHR)

The BHR forms 20% of the the Report Card Grade. The values in this sheets are calculated using the original method used since 2002-03 and is presented for comparison.