Application of Recent Red Abalone HALIOTIS RUFESCENS Surveys to Management Decisions Outlined in the California Abalone Recovery and Management Plan

Abstract

The management section of California's recently adopted Abalone Recovery and Management Plan (ARMP) uses results of fishery independent transect surveys at eight index sites to regulate total allowable catch (TAC) for the recreational red abalone, Haliotis rufescens (Swainson), fishery. The ARMP uses abalone densities over all depths, densities in deep water (8.4–19.7 m), and successful recruitment (>4,500 abalone/hectare in the 100–177 mm size class) to decide whether changes need to be made in the TAC (see Table 1 later). The catch is estimated from telephone surveys and returned abalone permit report cards. Recent surveys in 2003 and 2005 at four of the eight index sites show red abalone densities in the range of the baseline densities established by surveys in 1999 and 2000. Applying the results of the 2003 and 2005 surveys to the ARMP criteria indicates no change is needed in the current TAC. Two-way ANOVA showed there were no significant differences in density between sites (Van Damme and Salt Point; df = 1, F = 0.06, P > 0.8) and time periods (df = 1, F = 1.33, P > 0.25) for all depths combined. Likewise there were no significant differences at deep depths between the two sites (df = 1, F = 0.23, P > 0.63) and the two time periods (df = 1, F = 0.10, P > 0.75).