The East Harbor coastal lagoon and salt marsh system (Truro, Massachusetts) has been artificially isolated from Cape Cod Bay since 1868, when its inlet was filled by a causeway. A drainage system at the south end of the embayment was installed in 1894 to allow freshwater to escape. The lack of tidal flow caused salinity to decline from estuarine to near freshwater conditions and water quality to deteriorate over the last century. Following a severe oxygen depletion event and subsequent fish kill in 2001, the clapper valves in the 4-foot diameter drainage pipe were opened in November 2002, opening the system to limited tidal exchange with Cape Cod Bay. Since the restoration of tidal flow, native fauna have been reestablished in East Harbor, including horseshoe crabs (Limulus polyphemus) several species of commercially and recreationally valuable bivalve molluscs, notably the soft-shell “steamer” clam (Mya arenaria), hard clam or quahog (Mercenaria mercenaria), and blue mussel (Mytilus edulis). To begin to evaluate the degree to which East Harbor maintains self-sustaining marine benthic invertebrate populations and serves as a source of larvae to adjacent coastal waters, a pilot study of planktonic larval dynamics was conducted in summer 2016. Bivalve molluscs and horseshoe crabs produce planktonic larvae that are subject to passive transport by currents before settling on bottom substrate. Comparison of samples collected during ebb and flood tides can be used to determine the amount and direction of net larval flux between the East Harbor lagoon and Moon Pond and between Moon Pond and Cape Cod Bay. However, zooplankton sampling in shallow, turbulent, 'dirty' environments is fraught with challenges, rendering quantitative sampling using traditional conical nets unfeasible. A novel low-volume portable pump sampler was developed and tested for this application in summer 2017. The results of this pilot project will be used to inform sampling design for an upcoming larger-scale study.
Bio: Owen Nichols has been Director of Marine Fisheries Research at the Center for Coastal Studies since 2008, where he conducts research in collaboration with Cape Cod fishermen and shellfish farmers. His primary interests include distributional ecology, fisheries oceanography, marine mammal/fishery interactions, and ecosystem-based fishery management. Owen is a Ph.D. candidate at the University of Massachusetts - Dartmouth (UMassD) School for Marine Science and Technology, a guest investigator at the Woods Hole Oceanographic Institution, and an adjunct professor at the Massachusetts Maritime Academy. Owen holds a B.A. in Marine Affairs from the University of Rhode Island and a M.Sc. in Marine Science and Technology from UMassD. Owen was the 2016 recipient of the John H. Annala Fishery Leadership Award presented by the Gulf of Maine Research Institute.
2017 Nickerson Fellow Owen C. Nichols
Last updated: June 21, 2018