lalandi and revealed no clear effect of protection. lalandi in NTMRs, the traditional CI assessment explained only 3% of the variation in the abundance of S. We compared assessments which did and did not account for structural complexity, quantified using high resolution multibeam bathymetry. To determine the importance of structural complexity in evaluations of NTMR effectiveness we performed assessments on the abundance of a targeted fish, yellowtail kingfish (Seriola lalandi), in the Lord Howe Island Marine Park (LHIMP). Even with independent replicate areas among management zones, this approach can make it difficult to detect zone effects if seascape attributes, such as habitat structural complexity varies among experimental areas. In most cases baseline data are lacking, resulting in evaluations of NTMR effectiveness being Control Impact (CI) assessments. Seascape variability may confound assessments on the effectiveness of no-take marine reserves (NTMRs) in conserving biodiversity. The irregular shelf morphology appears to determine the distribution and character of sandy substrates and local oceanographic conditions, which in turn influence the distribution of different types of infauna communities. Infauna species abundance and richness were similar for sediment samples collected on the outer shelf and relict reef, while samples from the basin had significantly lower infauna abundance and richness. Offshore of the relict reef is a relatively flat outer shelf (mean depth 60 m) with bedrock exposures and sandy habitat. Inshore of the relict reef a sandy basin (mean depth 45 m) has thick sand deposits. The relict reef comprises sand sheet, macroalgae, and hardground habitats. As part of a large collaborative program of marine biodiversity research, the shelf around Lord Howe Island was selected as an area representative of a shallow (20-120 m) mid-ocean carbonate shelf environment. Erosion of these basalts has dominated island evolution since the cessation of volcanism, creating a rhomboidal-shaped shelf around Lord Howe Island, 24 km wide and 36 km from north to south. This remote island is the subaerial remnant of a hot-spot volcano that erupted between 6.6 and 7.2 Ma and comprises a mid-ocean basaltic sequence. Lord Howe Island (31☃3'S, 159☀4'E) sits approximately 580 km east of Australia in the southwest Pacific Ocean.

Island volcano cave submarine cartoon