Monday, September 13, 2010
Hall B (Convention Center)
The Maryland Biological Stream Survey (MBSS) is a probability-based monitoring program that provides unbiased estimates of stream conditions with known precision at spatial scales ranging from watersheds to river basins to the entire state. As of 2009, water quality, biology, physical habitat, and land use/land cover data were compiled from almost 3,500 stream sites. MBSS data were used to develop multi-metric biological indices that support biocriteria. Based on benthic macroinvertebrate and fish community indices, streams are placed on the State’s 303d list of impaired waters or designated as Tier II (high quality) waters. During the first statewide round of the MBSS (1995-1997), 95% of the sampled sites were randomly selected. The second round (2000-2004) sampling design was modified to continue a core of randomly-selected sites plus targeted sites for special studies. A network of 25 minimally-disturbed Sentinel Sites was established in 2000 to track weather-related changes in stream conditions and responses to climate change. By 2004, 81% of the MBSS sites were randomly selected and 19% were targeted. The MBSS sampling design continued to evolve to address new management questions. With completion of the third round in 2009, 43% of the sampled sites were randomly-selected and the rest targeted.