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Eelgrass 1948 – University of New HampshireA 1949 University of New Hampshire M. Sc. thesis by Stanley Bradley Krochmal contained a carefully drawn eelgrass map that was scanned and rectified to the NHD 1:24000 shoreline by The Nature Conservancy for the Great Bay Estuary Restoration Compendium. Polygons with density codes were traced onscreen from this image. The original map closely matches modern hydrology data and shows extensive eelgrass beds in the Oyster River and other areas where it is no longer found, and some areas, notably the south east shore of Great Bay apparently did not contain eelgrass at the time of his survey. Krochmal indicated that he did survey these areas. Krochmal was likely using primarily shore-based methods at low tide and the absence of eelgrass beds from deeper areas on his maps should be interpreted accordingly. Geospatial information from map, which covers lower Squamscott, all of the Lamprey, all of the Oyster, lower Bellamy, Great Bay, Little Bay, and some of the Upper Piscataqua. General narrative information about the presence of eelgrass in other rivers (e.g. Cocheco, Salmon Falls).Eelgrass densities: P “isolated patches”, S “one quarter of available area covered”, C “one half or over of the site is covered”. Assuming that S is the lowest density that would be mapped by current methods.The full thesis can be downloaded from the UNH Digital Library (http://www.library.unh.edu/digital/). Search the archives for “Krochmal”. The citation for the thesis is: Krochmal, Stanley Bradley. 1949. The ecology of the smelt, Osmerus mordax mordax (Mitchell) in Great Bay, New Hampshire.Citation for the Great Bay Restoration Compendium:Odell, J., Eberhardt, A., Burdick, D., and P. Ingraham. 2006. Great Bay Estuary Restoration Compendium. Report to the Piscataqua Region Estuaries Partnership and the New Hampshire Coastal Program, Durham and Portsmouth, NH. Published online: Published online: http://prep.unh.edu/resources/pdf/great_bay_restoration-tnc-06.pdf. |