4.8 Mucous sheet production in Porites

Description

The function and biological role of the mucous sheet has been previously explored, yet studies involving exposure to altered environmental conditions (temperature, salinity and especially sediment) have produced equivocal results. In this study, multiple lines of convincing evidence are presented from both field observations during a large-scale dredging project, and from controlled laboratory-based studies, to suggest a close association between mucous sheet production and sediments.

Aims

• Using information from observations during a large-scale, capital dredging project, examine the relationship between mucous sheet formation in massive/sub-massive Porites spp., and dredge related sediment pressures.
• To test whether temporal patterns and spatial distributions of mucous sheet formation can be explained by timing and proximity to dredging, and whether sheet formation is influenced or driven by other environmental factors such as lunar periodicity and temperature.
• To test whether mucous sheet formation can be induced in Porites spp. in a controlled, laboratory-based manipulative study, involving exposure to a range of high suspended sediment concentrations and sediment deposition rates.