A Decade of Scuba Effort Reevaluates Approach for Surveying White Abalone (Haliotis sorenseni Bartsch, 1940) Journal of Shellfish Research

Accurate distribution and density data of endangered marine species may be complicated by artifacts from exploitation, survey design, and general difficulty in accessing subtidal habitats. Occasional review of survey data may help restructure survey efforts to improve conservation outcomes. The white abalone (Haliotis sorenseni) is a marine gastropod listed under the Endangered Species Act thought to primarily inhabit depths beyond conventional scientific SCUBA limits (30–60 m) in the southern California Channel Islands. This study reviews surveys at four Channel Islands and four locations along the south- ern California mainland coast within SCUBA depth ranges and conducts a simulation comparison of the larger survey design used for this study with the standard transect approach presently common in the region. White abalone density was greater along