A resource survey of the Alexandra Reef Complex off Port Douglas, north Queensland

The Alexandra Reef complex is a collection of fringing reefs which extend over 8 km along the coast and up to 3 km seaward between Yule Point in the south and Port Douglas in the north. The reef complex is centered around the mouth of the Mowbray River.

Two transects across the reef flat at the northern and southern extremities of the complex were assessed qualitatively during the low tide period. Data collected included, community types (zones), the width of the zone (m), depth at low tide (m), substrate type and cover of algae, sea grass, hard coral, soft coral and other organisms. Organisms were identified to species where possible.

Sub-tidal communities were examined at eight sites along the outer margin of the reefs. At each site, both investigators swam for a timed period of 5 minutes and recorded data on exposure, depth (m), width of zone (m), substrate type, visibility (m) and percent cover of algae, hard corals, soft corals and other organisms. Organisms were identified to species where possible. The estimates of each investigator were combined.