3129 - Laserfiche WebLink

Home Browse Search

~. y ~ ~ _ _ l S• ~^ ' 031.2q • g cl,1~; n,_nc 'ic :ior. er .. lc ~... sc~:av.`T~Y': ~ r , ~. (Ftvchocheiln~ lucius) in the Pampa and Green lovers, Colorado and Utah, 1981. H. A7. Tyus, E. J. Z•:ick and D. L. Skates U. S. Fish and Wildlife Service 447 E. Main St., Vernal, UT 84078 Abstract 'Spawning migration of Colorado squawfish has been hypothesized but never documented until late June and early July, 1981 when eight Colorado squawfish were radio- tracked from the upper Yampa and lower Green Rivers to spawning grounds in the lower 32 Km of the Yampa River. Seven Colorado squawfish migrated from 80 to 160 Km down- stream in the Yampa River and one migrated 154 Km upstream from the Green River to enter the spawning grounds. Radio- tagged fish remained in the lower Yampa from June 26 to .July 10 and seven were relocated at their approximate pre- migratory location approximately two weeks after this period. Three Colorado squawfish originally tagged with dangler tags on the upper Yampa ~tiver in 1978 and 1980 and on the upper Green River in 1981 were recaptured on the spawning grounds from June 18 to July 9. Collection of larval Colorado squaw- fish in the lower 20 Km of the Yampa River confirmed that successful spawning occurred. Outline 1. Introduction Provides background, setting, and objectives of USFWS studies on Green and Yampa Rivers and Colorado DOW larval studies on Yampa River. 2. Methods States techniques used for radiotelemetry and conventional tagging with dangler tags, including how fish were handled and the way they were tracked. Also provides some information on larval collections; 3. Results Presents tables and figures with the dates, locations and movements of Colorado ' squawfish. Text provides detailed information on movement of Colorado squawfish and description of the identified spawning area. Some results of larval collec- tions by Colorado DOW is also provided. 4. Discussion , The findings of this study is related to the h~thereri e Coloradomsquawfish f other squawfish species and past collections o P The characterization of the identified spawning grounds is defended and migra- tion in freshwater fish is discussed.