Wednesday, August 8, 2007 - 1:30 PM

COS 97-1: Bay scallop (Argopecten irradians) habitat attributes in a Massachusetts salt pond with active scallop restoration efforts

Marnita M. Chintala1, Eric J Weissberger1, and David W. Grunden2. (1) U. S. Environmental Protection Agency, (2) Town of Oak Bluffs

Habitat quality and quantity are important factors to consider when restoring bay scallop (Argopecten irradians) populations. However, data linking habitat attributes to bay scallop populations are lacking. This information is essential to guide restoration efforts to reverse scallop declines. Initial results of dive surveys conducted in September, 2005 and 2006 in Lagoon Pond, Martha’s Vineyard, MA indicated a correlation between scallop abundance and total vegetated cover (macroalgae and eelgrass combined), depth, and sediment type. Eelgrass alone did not determine the location of scallops. Scallop abundance was highest (15.42 scallops m-2 in 2005 and 80.3 scallops m-2 in 2006) at sites where average total vegetated cover was 24% and 88%, respectively. More scallops were found in shallower areas (1-5 m depth) along the pond edge, with deeper, unvegetated sites comprised of > 75% fine sediment (< 250 mm) devoid of scallops. Shell height (measured from umbo to opposite edge) ranged from 10 to 90 mm, with larger scallops present in the northern pond areas in both years. Scallop abundance tended to be higher near sites of active restoration (spawning cages in both years and direct seeding in 2005), but that might be related more to pond hydrodynamics than habitat influences. By linking habitat attributes with system-level driving forces, such as hydrodynamics and land use, we might be able to predict success of restoration activities better in the future.