California Sea Grant College Program

Our overall research objectives were to (1) assess population trends along San Nicolas Island and in Monterey County; (2) optimize black abalone spawning methods; (3) develop and validate a real-time PCR assay for quantification of RLP loads (infection intensity); and (4) examine if progeny of surviving black abalone along the California islands are more resistant to WS than are animals without this disease pressure. At UCSB we were focused primarily on objective (2). We tested the following hypotheses to fulfill our objectives.

Hypothesis 1: Black abalone spawning requires environmental conditions similar to their intertidal and shallow subtidal habitat, and not standard methods that were developed for subtidal species. Hypothesis 2: Quantitative real-time PCR can be used to quantify loads of the WS rickettsial bacterium (infection intensity) in abalone. Hypothesis 3: Juvenile black abalone recruiting along the California Channel Islands are more resistant to WS than are black abalone in northern Central California that have not experienced high disease (WS) selection pressure.