Comparison of Large River Fish Index of Biological Integrities (IBIs) in the Allegheny and Monongahela Rivers in Pennsylvania

Since 2006, The Commonwealth of Pennsylvania has conducted statewide surveys (mainly macroinvertebrate and habitat) in its wadeable rivers to assess current conditions.  However, no such program exists to evaluate non-wadeable rivers.  From 2008 to 2010, we conducted an integrated large river assessment using water quality, physical habitat, and biological measures on portions of the Monongahela and Allegheny Rivers in Pennsylvania.  The biological components of the assessment included fish, benthic macroinvertebrate, and mussel sampling. The objective was to build Pennsylvania’s capacity to assess conditions of large rivers by providing a foundation for the development of large river assessment protocols for non-wadeable streams.  Fish were collected at 157 500-meter long sites over the three year sampling effort. The fish data will be incorporated into the Modified Ohio River Fish Index (MORFIN) developed by Ohio River Sanitation Commission and the Great Rivers Fish Index (GRFIN) developed by U.S. EPA in Duluth, Minnesota. Using these existing models will allow us to gauge whether our large rivers are attaining their designated uses with respect to fish species.  We are also currently working on developing a similar assessment tool for our mid-sized non-wadeable streams.