THE DISTRIBUTION OF TENDIPES PLUMOSUS (LINNÉ) IN MINERAL ACID WATER1

Tendipedid populations from 19 strip-mine lakes of varying pI1 were analyzed. Tendipes plumosus (Linnb) was the sole tendipcdid established in water with measurable potential free acidity. In lakes lacking potential free acidity, T. plumosus, when present, was frequently accompanied by other tendipcdid species. It is suggested that the distribution of T. plumosus was not restricted by a mineral acid environment, but was related to the presence of leaf litter. The process of strip-mining coal commonly leaves pits which subsequently fill with water. Initially, many such lakes contain water contaminated with sulfuric acid formed from the oxidation of sulfur compounds associated with the coal (Parsons 1956; Campbell et al. 1964). High concentrations of hydrogen ions severely limit the biota in such waters (Lackey 1938,1939; Crawford 1942; Heaton 1951; Riley 1960; Campbell et al. 1964, 1965). One of the species most tolerant of these acid waters is Tendipes plumosus ( Linn& ) . The distribution and abundance of T. plumosus in 19 acid and near-acid strip-mine lakes were analyzed to determine if the distribution of this species is limited by acidity and to compare the tolerance of this species with the tolerance of other tendipcdid species to the same mineral acid environments. We are most grateful to LaVcrne L. Curry for assistance in identification of the Tcndipedidae, and to John E. Letter, Jr., for chemical analyses. Richard 0. Anderson and LaVerne L. Curry read the manuscript. STUDY AREA AND METHODS Twelve strip-mine lakes were sampled in Callaway County and two in Boone County, Missouri; five were sampled in Crawford County, Kansas. In four of the Callaway .1 Contribution from the Missouri Cooperative Fishery Unit: Missouri Department of Conservation, U.S. Bureau of Sport Fisheries and Wildlife, and University of Missouri coopcrating. This invcstigation was supported in part by Public County lakes, water and bottom samples were gathered monthly over a two-year period. Bottom samples ( 102), secured with a 6-inch2 (15.2 cm2) Ekman dredge, were washed through a screen of 30 sq/linear inch ( 11.8 sq/linear cm). Larvae were preserved in 5% formalin, later sorted by sugar flotation (Anderson 1959 ), and transfcrred to 70% alcohol. Qualitative samples wcrc procured with a dip net. Water acidity was determined with each collection; there were 134 water samples. Mud samples for pH determination were procured by pushing a plastic tube (2.54-cm diam) into the sediment deep enough to penetrate the underlying compacted clay, withdrawing it, stoppcring both ends, and freezing with Dry ICC. The tube was later sectioned into l-cm lengths, thawed, and pH determined with a Radiometer pH meter. Multiple determinations of water ~1-1 were made with Beckman Zcromatic and Fisher Accumct pH meters and a Hach colorimetcr. Potential free acidity ( Rainwater and Thatcher 1960) was measured with phenolphthalcin. Potential free acidity reprcscnts the existing acidity from all causes and includes that which may develop from acid-producing salts but excludes that from uncombined gases (Rainwater and Thatcher 1960). Specific conductance was Health Scrvicc Grant Number WP-00379 from the Division of Water Supply and Pollution Control. This investigation was conducted in part on the Cedar Creek Land USC Area under the administration of the U.S. Forest Service.