Dataset 227

Coastal ecological data from the Virginian Biogeographic Province 1990 to 1993

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Realm: Marine
Climate: Temperate
Biome: Temperate shelf and seas ecoregions
Central latitude: 39.787579
Central longitude: -74.133736
Duration: 4 years, from 1990 to 1993

1868 records

107 distinct species

Across the time series Trinectes maculatus is the most frequently occurring species

Methods

2. Site description: Random estuarine and coastal stations in the Virginian Biogeographic Province. northeast USA. from Cape Cod. Massachusetts south to Cape Henry. Virginia at the mouth of Chesapeake Bay.a. Site type: Estuarine and coastal waters.b. Geography: The Virginian Biogeographic Province. It is composed of 23.574 km2 of estuaries. including 11.469 km2 in Chesapeake Bay and 3.344 km2 in Long Island Sound. Bounded by latitude 36 degrees. 49 minutes to 42 degrees. 09 minutes; longitude -77 degrees. 24 minutes to -69 degrees. 56 minutes.c. Habitat: Subtidal marine bottom and water column.d. Geology: Not applicable.e. Watersheds. hydrology: Not applicable.f. Site history: Not applicable.g. Climate: Coastal northeastern USA.3. Experimental or sampling designa. Design characteristics: Estuaries were classified into three classes (or strata): large estuarine systems. small estuarine systems. and large tidal rivers (Holland 1990). Large estuarine systems are defined as systems having surface areas greater than 260 km2 and aspect ratios (length/average width) less than 18. Twelve large estuarine systems with a total surface area of 16.097 km2 or 68% of the Province's estuarine area met these criteria. Large tidal rivers. defined as systems having surface areas greater than 260 km2 and aspect ratios greater than 18. included the Hudson. Potomac. James. Delaware. and Rappahannock Rivers. These five tidal rivers have a total surface area of 2.601 km2 or 11% of the total Province area. Small estuarine systems are defined as systems having surface areas less than 260 km2 but greater than or equal to 2.6 km2 . There were 144 small estuarine systems with a total surface area of 4.875 km2 or 21% of the Province.Sampling sites in the large estuarine class were selected using a randomly placed systematic grid (Holland 1990. Paul et al. 1992). The distance between the systematically spaced sampling points on the grid was approximately 18 km. The grid is an extension of the systematic EMAP grid (Overton et al. 1991). The center points of the grids are the sample sites. A linear analog of the systematic grid was used for site selection in the large tidal rivers (Holland 1990. Paul et al. 1992). The grid was used to define the spine of the five large tidal rivers. with a starting point at the river mouth. The first transect was randomly located between river kilometer 0 and 25. Additional transects were then placed every 25 km up the river to the head of tide. The 144 small estuarine systems were randomly selected from the entire list of small systems in the Province (Holland 1990. Paul et al. 1992). They were ordered from north to south by combining adjacent estuaries into groups of four. One estuary was selected randomly from each group without replacement for each of the four years of sampling. The location of the sample within each selected small system was randomly placed. Application of the sampling design to the three estuarine resource classes resulted in 446 potential sampling sites; however. 21 were unsampleable due to inadequate water depth or inaccessibility. so 425 sites were sampled over the four-year period (Fig. D1).b. Permanent plots: Not applicable.c. Data collection frequency: An index period (July?September) was chosen for estuarine sampling to represent that portion of the year when the measured ecological parameters are expected to show the maximum response to pollutant stress (Connell and Miller 1984. Sprague 1985); dissolved oxygen concentrations are lowest (Officer et al. 1984. USEPA 1984); fauna and flora are most abundant; and within-season variability is expected to be minimized. The Virginian Province survey was conducted annually. during the index period from 1990 through 1993. Generally. each station was visited once. Base Sampling Sites (BSS) are the probability-based sites that form the core of the monitoring design and are the basis of this data paper. Crews sampled 425 base stations during the index period over four years.4. Research methods: An important aspect of the EMAP Virginian Province project was that the data were collected and processed with consistent methods. Field methods are documented in the Field Operations and Safety Manual (Reifsteck et al. 1993). Laboratory methods are given in the EMAP-Estuaries Laboratory Methods Manual (USEPA 1995). A performance-based approach was used for chemical analyses. consistent with the approach used by the NOAA National Status & Trends Program (Valette-Silver 1992). All sampling was conducted from small (24-ft) vessels. except for fish sampling at deep-water stations (> 25m). which were collected from larger vessels.a. Field/laboratory: Water column profiles for water quality parameters were collected using a SeaBird SBE-25 Sea Logger CTD. The unit was equipped with probes to measure salinity. temperature. depth. pH. dissolved oxygen (DO). light transmission. fluorescence. and photosynthetically active radiation (PAR). Water quality measurements were collected upon arrival at a sampling station; no effort was made to standardize for the time of day or stage of tide. The CTD was equilibrated at the sea surface. then lowered through the water column until reaching a depth of one meter above the bottom where the CTD was allowed to equilibrate again. The unit was then returned to the surface. where data were downloaded to an on-board computer for review and storage. If the CTD cast appeared unusual or failed quality control criteria. the cast was repeated. Beginning in 1991. a bottom water sample was collected. and the dissolved oxygen concentration determined with a YSI Model 58 DO meter. This measurement served as a check on the CTD probe as well as a back-up in case the CTD failed.Three benthic samples. if possible. were collected using a stainless steel. Young-modified van Veen grab that sampled a surface area of 440 cm2. A small core (2-cm diameter) was collected from each grab for sediment grain size. The remaining sample was sieved through a 0.5-mm screen using a backwash technique that minimized damage to soft-bodied animals. Samples were preserved in 10% formalin-rose bengal solution and stored for at least 30 days prior to processing to assure proper fixation. In the laboratory. macrobenthic community samples were transferred from formalin to an ethanol solution and sorted. Biomass was measured for key taxa and all other taxa were grouped according to taxonomic type.Fish were collected by trawling with a 15-m. high-rise otter trawl with a 2.5-cm mesh cod end. The net was towed for 10 minutes against the tide between 0.5 and 1.5 m/s (1?3 knots). All fish caught in the trawl were identified to species and counted; up to 30 individuals of a species from each collection were measured to the nearest millimeter. Individuals collected in standard trawls were inspected for gross external pathological disorders at all stations where fish were collected. This included checking body surface and fins for lumps. growths. ulcers. and fin erosion. Specimens with observed gross pathologies were preserved in Dietrich's solution for subsequent laboratory verification and histological examination.An additional 6?10 sediment grabs at each station were taken for sediment chemistry and toxicity analyses. The top 2 cm of sediment was removed from each grab using a stainless steel spoon and thoroughly homogenized in a stainless steel pot. Sediment for chemistry analyses was placed in clean glass jars with Teflon liners or polypropylene containers (for organic and metals analyses. respectively). shipped on ice. and stored frozen in the laboratory prior to analysis for contaminants. Sediments were analyzed for 24 polycyclic aromatic hydrocarbons (PAHs). 18 polychlorinated biphenyl (PCB) congeners. DDTs. 11 chlorinated pesticides. butyl tins. and 15 metals. The chemical analyte list is the same as used in the NOAA NS&T Program (NOAA 1992). An additional aliquot was placed in a small polyethylene bag and refrigerated for grain size analysis. The remainder of the composite sample (> 3.000 mL) was placed in a clean plastic jar for sediment toxicity testing.Toxicity tests were performed on the composite sediment samples from each station using the standard 10-day acute test method (USEPA 1994. USEPA 1995) and the tube-dwelling amphipod Ampelisca abdita. Amphipods were exposed to sediment from the site for 10 d under static conditions in 1-L glass test chambers. Five replicates per station were tested with 20 amphipods per replicate. A performance control was run with each test. as was a water-only test using a reference toxicant (Cu or sodium dodecyl sulfate) to evaluate the condition of the test organisms. Eighty-five percent survival in the sediment control was required for a test to be valid. To normalize for test conditions and amphipod health. survival among treatments is expressed as percent of control survival.Further descriptions of the methods used are given in the Near Coastal Program Plan (Holland 1990). the Virginian Province Implementation Plan (Schimmel 1990). the 1993 Virginian Province Field Operations and Safety Manual (Reifsteck et al. 1993). and the EMAP-Estuaries Laboratory Methods Manual (USEPA 1995).b. Instrumentation: (See Reifsteck et al. 1993. USEPA 1995).c. Taxonomy and systematics: Hundreds of species of benthic invertebrates and demersal fishes were captured and identified (see Reifsteck et al. 1993 and USEPA 1995 for taxonomic methods).d. Permit history: (See Reifsteck et al. 1993).e. Legal requirements: Clean Water Act.5. Project personnel: (See Strobel et al. 1995).6. Funding sources: U.S. Environmental Protection Agency. Unit of abundance = IndCountInt, Unit of biomass = NA

Citation(s)

Hale, S. S., Hughes, M. M., Strobel, C. J., Buffum, H. W., Copeland, J. L. & Paul, J. F. (2002) Coastal ecological data from the Virginian Biogeographic Province, 1990–1993. Ecology, 83, 2942.