The effects of mountaintop removal and valley fill activities on the fish communities of Twentymile Creek (Fayette County, West Virginia): Comparison of 2000 versus 2007/2008 bioassessments- what happened to the percids?

In 2000, fish were collected as part of the USEPA Mountaintop Removal/Valley Fill Environmental Impact Statement (MTR/VF EIS) study and by the coal industry within the Twentymile Creek Watershed (Fayette County, West Virginia).  USEPA re-sampled the original locations in 2007 and 2008 in response to a documented 10-fold increase in the in-situ conductivity levels (250 µS/cm versus 2600 µS/cm) of the mainstem of Twentymile Creek.  The West Virginia Fish Index of Biotic Integrity (WV-IBI) was used to assess the condition of the stream’s fish community.  Mining activity has continued in the watershed between 2000 and 2007/2008 with some of the major tributaries being over 80% mined and filled.  The effects of the increased mining activity has increased the in-situ conductivity levels within the stream and have documented a clear adverse effect on the benthic macroinvertebrates as all of the monitoring sites have declined into the ‘impaired’ category according to the WVSCI.  However, the effects of the increased mining and increased conductivity are not as clear on the resident fisheries community.  The mainstem stations still support ‘good’ fish communities according to the WV-IBI; however, up to 3 species of darters have been lost from the fish community.