title: Benthic nepheloid layers in the Gulf of Maine andAlexandriumcyst inventories.
abstract: Cysts residing in benthic nepheloid layers (BNLs) documented in the Gulf of Maine have been proposed as a possible source of inoculum for annual blooms of a toxic dinoflagellate in the region. Herein we present a spatially extensive data set of the distribution and thickness of benthic nepheloid layers in the Gulf of Maine and the abundance and inventories of suspendedAlexandrium fundyensecysts within these near-bottom layers. BNLs are pervasive throughout the gulf and adjacent Bay of Fundy with maximum layer thicknesses of 50-60 m observed. Mean BNL thickness is 30 m in the eastern gulf and Bay of Fundy, and 20 m in the western gulf. Cyst densities in the near-bottom particle resuspension layers varied by three orders of magnitude across the gulf with maxima of 105cysts m-3. An important interconnection of elevated BNL cyst densities is observed between the Bay of Fundy, the Maine Coastal Current and the south-central region of the gulf. BNL cyst inventories estimated for the eastern and western gulf are each on the order of 1015cysts, whereas the BNL inventory in the Bay of Fundy is on the order of 1016. Although BNL cyst inventories in the eastern and western gulf are 1-2 orders of magnitude smaller than the abundance of cysts in the upper 1 cm of sediment in those regions, BNL and sediment-bound cyst inventories are comparable in the Bay of Fundy. The existence of widespread BNLs containing substantial cyst inventories indicates that these near-bottom layers represent an important source of germinatingA. fundyensecysts in the region.
authors.affiliation: School for Marine Science and Technology, University of Massachusetts Dartmouth, New Bedford, MA 02744, USA.
authors.forename: C H
authors.initials: CH
authors.lastname: Pilskaln
authors.affiliation: School for Marine Science and Technology, University of Massachusetts Dartmouth, New Bedford, MA 02744, USA.
authors.forename: K
authors.initials: K
authors.lastname: Hayashi
authors.affiliation: Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Keafer
authors.affiliation: Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Anderson
authors.affiliation: Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: McGillicuddy
keywords: Alexandrium fundyense; Benthic nepheloid layer; Cysts; Gulf of Maine; Suspended particulate matter