THE ASSOCIATION OF WATER CHEMISTRY VARIABLES AND FISH CONDITION IN STREAMS OF SHENANDOAH NATIONAL-PARK (USA)

As part of the ''Shenandoah National Park: Fish in Sensitive Habitats' ' (SNP:FISH) project, the blacknose dace (Rhinichthys atratulus) was u tilized as an indicator species to assess the susceptibility of the ic hthyofaunal community of Shenandoah National Park (USA) to acidificati on. Water chemistry (ANC, conductivity, pH, and concentrations of Ca2, Mg2+ Na+, K+, Cl- NO3-, SO42-, and SiO2) was sampled every three mon ths over the course of 31/4 years which represents the probable maximu m lifetime of R. atratulus. Condition factors (K = [g/mm(3)]10(6)) we re calculated for samples of fish (age class 2+ yr, n = 370) from nine montane, second/third order streams representing a range of ANCs. A p rinciple components regression was performed on factor scores from a p rinciple components analysis of the water chemistry variables and fish condition factor. Two factors, one associated with stream water ANC a nd ion concentrations, and another associated with SO42- concentration , collectively explained 84% of the variance in condition factor. The influence ofvariables other than water chemistry upon R. atratulus K i s addressed The results show that environmental chemistry is highly as sociated with the K of R. atratulus.