Record Display for the EPA National Library Catalog

RECORD NUMBER: 16 OF 35

Main Title Eelgrass Distribution in the Great Bay Estuary 2005. Final Report.
Author F. Short
CORP Author New Hampshire Univ., Durham. Jackson Estuarine Lab.
Year Published 2007
Stock Number PB2011-107450
Additional Subjects Eelgrass distribution ; Great Bay Estuary ; Habitat ; Waterfowl ; Junvenile fish ; Estuarine food ; Eelgrass(Zostera marina) ; Great Bay Estuary(GBE)
Holdings
Library Call Number Additional Info Location Last
Modified
Checkout
Status
NTIS  PB2011-107450 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 7p
Abstract
Eelgrass (Zostera marina) is an essential habitat for the Great Bay Estuary (GBE) because it provides food for wintering waterfowl and habitat for juvenile fish and shellfish. Eelgrass is the basis of an estuarine food chain that supports many of the recreationally, commercially and ecologically important species in the estuary. Additionally, eelgrass filters estuarine waters, removing both nutrients and suspended sediments from the water column. Eelgrass in the Great Bay Estuary is the largest monoculture in the State of New Hampshire and is considered a vital resource to the States marine environment. The present report describes and interprets the eelgrass distribution data collected in 2005 for the Great Bay Estuary. The Great Bay Estuary is experiencing an alarming decline in both eelgrass biomass and distribution that appears to be related to the declining water clarity of the estuary. Eelgrass biomass in Great Bay itself (grams of eelgrass per meter square) has declined steadily (Trowbridge 2006) over the past decade, although the distribution has been relatively constant in Great Bay for the past 10 years at approximately 2,000 acres. In the Piscataqua River, recent declines in both natural and transplanted eelgrass beds are now evident (Short and Beem, in prep) and are a combination of both loss of biomass and loss of distribution. In Portsmouth Harbor in the past 3 years, eelgrass has receded at the deep edge of the meadows, creating an overall loss of distribution which has been accompanied by losses in biomass (Rivers 2007). In this study, we refer to eelgrass biomass as measured by percent cover, i.e., the percent of the bottom which is vegetated with eelgrass. Biomass is determined through a regression of fieldmeasured biomass and field-measured percent cover. The percent cover map from the aerial distribution can then be converted to biomass (g dry weight eelgrass m-2).