The authors evaluated the effects of planning-unit size on emergent patterns of species-richness hotspots across the Gulf of Maine-Georges Bank Large Marine Ecosystem. The authors used data on the distribution of fishes as information for this taxon is the most geographically and temporally comprehensive due to their economic value and requirements for active and ongoing management. They also investigated both how spatial scale affects geographic patterns of species richness as well as the effect of sample size per planning unit on such patterns. An effort-standardization approach based on a bootstrap procedure was used to address variation in sample effort across the geographic region. In order to understand the equivalence of hotspots in terms of conservation value, the authors also investigated patterns of species similarity among hotspots across the gradient of planning-unit size.