Laserfiche WebLink
<br />1'1lJ-cb UC MUN 11 :bl AM ljU i'(iver i'(ecovery <br /> <br />rHK NU, jUj~O~lj~1 <br /> <br />r, Uq/ JU <br /> <br />OQHJ.8 <br /> <br />INTRODUCTION <br /> <br />This document was prepared by the Program Director's Office [or the Upper Colorado <br />River Endangered Fish Recovery Program. The purpose ofthis documcnt is to briefly describe <br />the current prolocols ami nl3kc recommendations lo revise those protocols for Colorado <br />pikeminnow (P/ychocheilus lllcills) and humpback ehub (Gila CyplUl) population estimatcs. <br />Population estimates will be used in assessiug population status related to the down listing and <br />deli sting demographic. critetia for the specics. To cnsure the greatest scientilic validity possible, <br />tbe Program Director convened a workshop of spccies expelts and statisticians in Fort Collins, <br />Colorado, on Decembcr 6-7, 2001. Sevcral issucs were identified at tbe workshop that Ileeded <br />fmtller investigation and reporting, and a subsequent meeting with ptincipal investigators was <br />hcld in Gmnd Junction, Colorado, on February 11, 2002, to furlher address and resolve lhese <br />issues. The rcsulls of the workshop and meeling are being assimilated into a separatc doclIlllent <br />that describes in greater detail the cllrrent population estimate protocols and recol11Jl1cnda(\ons to <br />revise tllosc protocols for morc precise estimates. A tentative schedule of estimates for e,lch <br />population is presented in Tablcs 1 and 2 of this docul11cl1t to providc a pcrspective of possible <br />sampling schedules for each population. <br /> <br />PROTOCOLS AND RECOMMENDATIONS <br /> <br />I. Colorado Pikemiullow <br /> <br />A. Upper Colorado River Suhbasin <br /> <br />!l.tmer Colorado l~iver (Price Stubbs Dam to Green ~iver confluence. eXcel)! rOl' Westwater <br />f'",anvoll) <br /> <br />Current Protocol: Block and shock during mid-April to mid-June. Reach is divided into two <br />sub-reaches (above Westwater Canyon and below Westwater Canyon). Two or threc sUlllpling <br />occasions arc dOlle about 1-2 weeks apart. The current estimate does not include Wcstwater <br />Canyon, the Gunnison River, or Cataract Canyon, and is therefore conservative. <br /> <br />Rcco11111lend;jtion~: <br />Estimates oCac1111ts will include lish :>450 mill TL; sllbadults will include 1Isl1400 <br />to 449 mill TL <br />. Greater erCort needs to be expcnded with larger or multiple crews to increase <br />precision, and shoreline elcctrofishing (in additiollto block nnd shock) to increase <br />captLlrc probability; at least three sampling occasions need to be conducled each <br />year in each of the two sub-reaches <br />The Gunnison River neeus to be included in the estimate; it is not necessary to <br />include Westwatcr Canyon and Cataract Canyon heeause of tile low numbers of <br />Colorado pikelllinnow in those reaches <br />. Conduct cstimates in each of3 conseclltive years followed by 2 years off <br /> <br />I <br />