Coastal and marine National Park unit managers and policy makers face a growing series of complex stressors that negatively impact the natural environment within parks, including rising sea surface temperatures (SSTs) (Casey and Cornillon, 2001; Jokiel and Brown, 2004), coastal development (Hooper and others, 2005), erosion, increased nutrient influx (LaPointe, 1997; Hu and others, 2004), and even rising sea levels (Done and Jones, 2006). The first step to managing, or mitigating, any of these threats is to know with a reasonable degree of certainty the benthic resources associated with each coastal or marine park unit by mapping those resources.