7154 - Laserfiche WebLink

Home Browse Search

27 Rare Fish Movements The original plan of this study called for sampling one section of the Green River (Jensen to Ouray) several times, continuously marking rare fishes and hopefully recapturing some. The study was changed when young-of-the-year squawfish were not found in the original study area, Therefore, emphasis was placed on locating young-of-the-year squawfish rather than recapturing marked juveniles from the primary study area. The marking of rare fishes continued throughout the study with the antici- pation that future studies may recapture some of the fishes. Twenty juvenile squawfish were tagged, 13 more were anal fin clipped. Four subadult squawfish were also tagged. One tagged juvenile was recap- tured at the site of release 4-1/2 hours later. Young-:-of-the-ye.ar.S4uaw.f.is.h. wereqlar~r than anticipated (35-55 mm) when e..ncount~redin Gray Canyon. A solution of Bismark brown Y dye was tryed on two squawfish. One showed signs of stress in 5 minutes, the other in 15 minutes. Partial anal fin clipping was also tryed as a po- tential marking technique. Two squawfish were clipped and observed for 30 minutes. No ill effects were noted. Although the samples were small in both tests, it was decided that a partial fin clip appeared the better technique. Movement of young-of-the-year squawfish was studied in detail in one backwater (see Appendix IV, upper photo). The area was seined five different times during a two-day period (Data sheets 77-293, 294, 300, 301, 302) and 4, 31,29, 11, and 12 young-of-the-year squawfish were