We all live upstream: Aquatic insect communities above the“Blue Line" in Central Appalachian headwater streams

Studies of aquatic insect communities in unmapped central Appalachian headwater streams were conducted in mountaintop removal/valley fill mine permit areas.  Samples were collected in winter starting at spring seeps and continuing downstream to “blue line” status as depicted in USGS 1:24,000 data.  Community composition included 94 taxa dominated by Ameletus, Pycnopsyche gentilis and Leuctra which occurred in all 7 coalfield regions, >90% of 30 streams, and >50% of 175 samples.  These and 5 other genera (Neophylax, Tipula abodominalis, Ephemerella, Sweltza, and Peltoperla) occurred in over 1/3 of samples.  Seventeen ubiquitous taxa occurred in all 7 regions and >50% of streams.  Many taxa live only in the very headwater reaches (Nigronia, Ostracerca, Sweltsa, Paraleptaphlebia, Homoplectra) well upstream of the “blue lines” depicted on topographic maps. Semivoltine taxa with 2 to 5 year aquatic larval stages including Yugus, Peltoperla, and Cordulagaster were found in greatest abundance in 40-50 hectare watersheds.  Aquatic insect taxa were distributed along a gradient of watershed size. Near complete turnover of taxa occured in the upper kilometer of streams.  Abundance, diversity, longevity, and ubiquity of aquatic insects suggest that these streams are neither intermittent nor ephemeral above the points where solid blue lines magically appear on USGS topographic maps.