Two different methods of establishing high-density spawner sanctuaries for bay scallop (Argopecten irradians irradians) restoration were evaluated over 2 years at a site in Northwest Harbor, East Hampton, New York, USA. Hatchery-reared scallops, which had been overwintered at nearby sites, were free-planted directly to the bottom in late March/ early April at an initial target density of 94-128 scallops/m 2 . In addition, scallops were stocked in off-bottom culture units consisting of three vertically stacked 15-mm mesh ADPI Ò bags at densities of 50, 100, or 200 scallops/bag (=117, 234, or 468 scallops/m 2 ), respectively. Survival of scallops differed significantly by year, planting method, and scallop source. Survival of free-planted scallops was generally lower than caged scallops. Better survival of free-planted scallops in 2005 versus 2006 likely reflected the presence of luxuriant eelgrass beds in 2005, which were absent in 2006. Survival of scallops in ADPI bags was not appreciably related to stocking density. Shell growth was highest for freeplanted scallops; in cages, growth was somewhat better at 50 versus 200 scallops/bag. Wet weights of epibionts were significantly higher in caged versus free-planted scallops. Reproductive condition of scallops stocked at 50/bag was usually higher than at 200/bag. Both free-planting and off-bottom systems yielded high densities of adult bay scallops at the time of spawning, which ensures a higher probability of successful fertilization of spawned eggs and thus a greater potential for success of restoration efforts.

Striped bass fingerlings of two sizes, 1.7 and 6.0g, were stocked in the fall of 1974 into floating cages placed in a sea water lagoon off of Shelter Island, New York. Duplicate stocking densities of 100, 200, 300 and 400 fish per 1.82m3 cage were established. Low water temperature (1.0 C) occurred in January and February 1975 and resulted in heavy mortality of the caged fish. In order to prevent the complete loss they were removed and overwintered in indoor pools from February until June at which time they were restocked in the floating cages at densities of 50 and 90 fish per cage. The mean growth rates by stocking densities indicated that fastest growth occurred with 100 fish per cage. Owing to mishaps which included escapes from the cages and mortalities, only 14% of the fingerlings stocked were harvestable as 0.25 and 0.5 Kg fish in the fall of 1975. The mean dress‐out weight of these 280 fish was 81%. Relative food conversion values were between 1.4 and 1.8:1.

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