PATTERNS OF ZONATION OF ASSEMBLAGES OF THE LUTJANIDAE, LETHRINIDAE AND SERRANIDAE (EPINEPHELINAE) WITHIN AND AMONG MID-SHELF AND OUTER-SHELF REEFS IN THE CENTRAL GREAT-BARRIER-REEF

Visual censuses were used to quantify the distribution and abundance o f the Lutjanidae, Lethrinidae and Serranidae in three reef zones (wind ward reef slope, lagoon, back reef) of three reefs on the mid shelf an d three reefs on the outer continental shelf in the central region of the Great Barrier Reef. Significant spatial variability was identified in the abundances of many species between locations (outer-shelf and mid-shelf communities), between reefs (high-abundance v. low-abundance reefs), and within reefs (characteristic communities within zones on individual reefs). Species of the Lutjanidae, Lethrinidae and Serranid ae were found to occur in assemblages that were characteristic of majo r zones (windward reef slopes, lagoons and leeward back reefs), this p attern being consistent within and among shelf locations. Care will ne ed to be taken in determining the appropriate spatial scales of sampli ng in any future experiments (e.g. manipulations of fishing pressure) to ensure that the effects of smaller-scale spatial differences are no t confounded when larger-scale comparisons are made.