OLD DOMINION UNIVERSITY Department of Biological Sciences Old Dominion University, Norfolk, Virginia 23529 Side-by-Side Comparison of Young Grab and Composite Petite Ponar Grab Samples for the Calculation of the Benthic Index of Biological Integrity (B-IBI) Prepared by Principal Investigators:

Multivariate comparisons (MANOVAs) of the top ten species density dominants .. 12 Table 4. Multivariate comparisons (MANOVAs) of the top ten species biomass dominants. 13 Table 5. Summary of ANOSIM and SIMPER analysis results on log-transformed species Introduction The Virginia Department of Environmental Quality (DEQ) intends to unite elements of its National Coastal Assessment Program (NCA) with its Chesapeake Bay Probabilistic Benthic Monitoring (CBP-PBM) Program beginning in the summer of 2005. The primary motivations for this decision were twofold. First, the probable reduction of federal grant support for the NCA Program after the summer of 2004 would require considerable restructuring of the of DEQ's estuarine probabilistic monitoring to continue with a comprehensive program in the future. Second, the current CBP-PBM Program has not provided sufficient data for the assessment of minor tidal tributary segments using the recently approved Benthic Index of Biotic Integrity (B-IBI) assessment method. A formal assessment methodology, using the standardized Chesapeake Bay Benthic IBI, was approved by the States of Virginia and Maryland, the Interstate Chesapeake Bay Program, and EPA Region 3 for the 2004 305(b) assessment. The sharing of objectives and resources among these two monitoring activities will provide a number of advantages to both monitoring programs and to the assessment process. 1. Chesapeake Bay Program a. Increase the number of B-IBI samples for the characterization of the minor tidal tributaries (at no extra resource expenditure). b. Associate the B-IBI data with other elements of the Sediment Quality Triad (SQT)-toxicity and chemical contaminants. c. Associate the B-IBI data with additional water column parameters – nutrients, chlorophyll, bacteria, clean metals, PAR and field parameter profiles – not collected during CBP probabilistic B-IBI sampling. 2. Estuarine ProbMon (NCA) Program (under reduced resources in 2005 and beyond) a. Provide a second screening element to the SQT (B-IBI + toxicity tests) prior to investing resources in the (relatively expensive) chemical analyses of sediment metals and organic contaminants, in the event that resources limit the number of chemical analyses that can be performed. b. Adding B-IBI data at these sites would relax the necessity of performing toxicity tests on two species to single species tests at each site, thus reducing per site resource requirements. c. Provide a possible increase in the annual number of probabilistic sites (current N = 35) in minor tidal tributaries within the CB drainage. 3. 305(b) Assessment (2006 and beyond) a. Association of the B-IBI evaluation with …