The data were mainly collected in the Far Northern Section Cross-Shelf Closure of the Great Barrier Reef Marine Park. Location approximately: 11-12 Degrees South Latitude, 143-144 Degrees East Longitude. The data consisted of: 1. Biological samples from prawn trawls, fish trawls, benthic dredge tows 2. Sediment samples 3. Seabird regurgitated pellets 4. Seabird counts 5. GPS Position data for trawls The study objectives were as follows: 1. A quantitative description of the physical environment, sediment characteristics, fishing effort, fish communities, epibenthic communities and prawn populations. 2. A comparison of the fish,benthic and prawn communities of areas closed to trawling with areas open to trawling. 3. An assessment of the impact of prawn trawling on benthic communities and fish communities. 4. A quantitative description of the composition of bycatch produced by prawn trawling in the Green Zone and the areas to the immediate north and south of the Zone. 5. A list of the species trawled animals other than prawns returned to the sea and whether they float or sink and quantification of the fate of the dead material. 6.Quantitative estimates of the importance of trawl discards in the diets of seabirds, the degree of dependence on such discards and the effects of discards on seabird populations.