Some Phases of the Life History and Relationships of the Cyprinid, Clinostomus elongatus (Kirtland)

Abstract

W HILE Stuart M. Brown, Jr., and I were fishing in a small stream south f Ithaca, New York, on May 16, 1936, we found ripe male and nearly ripe females of the red-sided dace, Clinostomus elongatus (Kirtland). Realizing that the life history of this species was practically unknown, studies were made of its spawning habits and related phenonoma. The stream, Danby Creek, which drains into the Susquehanna River, flows through low open pastures and alder thickets. It is a typical small creek of the upland pool and riffle type having a bottom composed largely of rubble, with some slabboulders and occasional small areas of gravel. The width and depth vary considerably. At the area studied, about one-half mile northwest of the Tompkins-Tioga County line, the width ranges from about 2 to 6 meters (6 to 20 feet); the depth in the riffles varies from 5 to 10 centimeters (2 to 4 inches) and in the pools from somewhat less than a third to slightly over a meter (1 to 3Y2 feet). The red-sided dace is fairly common in some of the pools, especially those in the cleared areas where they are associated with common suckers, Catostomus c. commersonii; horned dace, Semotilus a. atromaculatus; black-nosed dace, Rhinichthys a. atratulus; common shiners, Notropis c. cornutus; pearly minnows, Margariscus m. margarita; stone-roller minnows, Campostoma anomalum; margined stone-cats, Schilbeodes insignis; Johnny darters, Boleosoma nigrum olmstedi and sculpins, Cottus b. bairdii. The suckers, homed dace, black-nosed dace, and common shiners are the most prevalent forms. Because the red-sided dace are neither especially numerous nor uniformly distributed in the stream, a survey was made to locate as many of the schools as possible in order to find the most advantageous places for study. The activities of about three of the schools which were most favorably situated were followed closely while those of others were checked once every day or two. Gravelly areas were also noted because the rather high frequency of hybridization between this fish and the common shiner or the horned dace seemed to indicate that they frequently spawned in the proximity of spawning pairs of these species which deposit their eggs in gravel. The region studied in greatest detail consisted of a more or less h-shaped area in which the vertical portions of the 'h' were pools and the horizontal portion a riffle. The standard of the 'h' consisted of a long shallow pool about 3 decimeters (1 foot) deep which drained at its side across a gravel bed at the end of which came the riffle proper. The lower end of the riffle was deflected so that the succeeding pool lay parallel with the lower end of the upper pool. The bottom was mostly rubble mixed with some gravel in all parts except about the first half of the horizontal region of the 'h' where it consisted almost entirely of fine gravel mostly less than 1Y2 centimeters (Y2 inch) in diameter. The depth was about 3 to 8 centimeters (1 to 3 inches) 1 This work was done at Cornell University.