| Populations of pinto (northern) abalone, native to the Puget Sound Georgia Basin, have declined significantly over the past 15 years, with very little recruitment of juvenile and young adults. Our working hypothesis is that the lack of recruitment is the direct result of low adult abundance and overall density; since abalone broadcast their gametes into the water column, fertilization can only take place if abalone are relatively close together in an aggregation. We will establish two experimental aggregations of wild pinto abalone, one made up of 20-30 lone wild individuals, and the other from a similar number of health-screened individuals that have been held as broodstock in our NOAA restoration hatchery facility, to elucidate differences in survival, movement, and aggregation persistence. As the ultimate goal of this work is to increase reproductive success, in year 2 of the grant we will exhaustively survey the aggregation sites for juveniles. Those found will be genotyped to determine whether they are likely to be progeny of aggregated individuals, since recruitment is thought to be localized. If supplementation program broodstock and wild abalone exhibit high survival and their aggregation behavior proves similar, we may adapt our restoration approach to include annual procurement of lone wild individuals for supplementation program broodstock and subsequent aggregation to increase future chances of successful reproduction in the wild.
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