Bay Scallop Restoration

      In the United States, the commercially important bay scallop (Argopecten irradians) has declined in most of the Atlantic and Gulf coastal areas where it was abundant in the 20th century. Bay scallops are particularly susceptible to population fluctuations because they usually live for only 18-22 months and reproduce once. On Long Island, New York, populations of the northern subspecies (A. irradians irradians) were nearly driven to extinction due to direct mortality and recruitment failures during "brown tide" (Aureococcus anophageferrens) algal blooms from 1985 to 1987, and in 1995. Despite the absence of brown tides since 1995, bay scallop populations have not recovered naturally; subsequent commercial harvests remained at 1-2 % of pre-brown tide levels and population densities in most areas were very low (< 0.1 individuals/m2). Our primary hypothesis for this lack of recovery is that local bay scallop densities and numbers were too low to permit high rates of successful fertilization of eggs during spawning.

     In our current work, funded by Suffolk County, New York, we are attempting to jump-start bay scallop populations by planting large numbers of hatchery-reared scallops at high densities (>75-100/m2) to ensure a high probability of fertilization success upon spawning. Since 2006, we have planted more than 5 million scallops (most >40 mm) – in lantern nets suspended in midwater as well as via free-planting to the bay bottom.

     In the last 6 years, we have spent 1000’s of hours on and under the water monitoring the progress of our restoration efforts; by all accounts it is clear that our efforts have greatly contributed to the resurgence of scallop populations in the Peconic Bays of eastern Long Island. In the areas where we have planted scallops, levels of larval recruitment to "spat" collectors (mesh bags suspended above the bay bottom), as well as abundance of juvenile and adult scallops, have increased dramatically in the 6 years (2007-2012) after spawning of our planted scallops compared to the 2 years prior to the start of our restoration work. Commercial harvests of bay scallops in the Peconic Bays have increased significantly and approached 100,000 lbs of meats in 2010 (~33% of historical harvest levels prior to the first brown tide). The resurgence of the fishery has provided a well-needed boost to the livelihood of local fishermen and the local economy


                                                                         Recent Publications