Spawning Population Characteristics of Alewife in Lake Mattamuskeet, 2015-2016

Abstract

Lake Mattamuskeet, a coastal lake draining to Pamlico Sound, is situated within Mattamuskeet National Wildlife Refuge in Hyde County, North Carolina. To prevent estuarine saltwater from entering the lake, water control structures have been placed in all four of the man-made outfall canals. These canals allow for the movement into and out of the lake of many aquatic species including the anadromous Alewife Alosa pseudoharengus. Populations of once abundant Alewife have declined to all-time lows, mainly due to habitat loss, or degradation and overfishing. The Lake Mattamuskeet Alewife population is limited by poor lake access to the spawning grounds during spring through the water control structures. There are currently two flapgate designs being used to control water passage through the Waupoppin Canal. One design is a top-hinged gate, while the other features a side-hinged gate. The objective of my study was to describe the length, weight, sex ratio, gonadosomatic index and condition factor of Alewife passing through the two gate designs in 2015 and 2016 and to determine whether one gate design was more efficient in Alewife passage. It was found that the side-hinged design allowed for a more efficient and varied passage of Alewife.