Laserfiche WebLink
<br />,.-. ,. .... ,...". <br />lIJJ~::l~ <br /> <br />7 <br /> <br />at fish >200mm, and should include a fish health assessment.) Maintain or enhance levels of <br />recruitment of HBC in the Little Colorado River. <br /> <br />MO 4: Maintain or enhance levels of recruitment ofHBC in the mainstem as indexed by size <br />frequency distributions and presence and strength of year-classes. (Focused at young-of-year and <br />juvenile fish, and should include a fish health assessment.) <br /> <br />(IN 3/4 relates to MO's 3 & 4) <br /> <br />IN 3/4.1 Determine adult HBC populations and evaluate life history schedules, <br />population health, and reproductive success. (Fall 97 RPM 1) <br /> <br />IN 3/4.2 Determine levels of recruitment of humpback chub in the mainstem and <br />the LCR. <br /> <br />IN 3/4.3 Develop and implement a program to evaluate effects of factors limiting. <br />overwintering survival of young- of-year HBC in the Grand Canyon (Fall <br />97, RPM 1). The program shall evaluate the effects of future test flows <br />(i.e., 25,000 cfs and greater) from October through February on young-of- <br />year HBC recruitment and over-wintering survival, habitat restrictions, <br />predation, reduced sediment loads, and cold water temperatures. (Fall 97 <br />Test Flow T&C 1) This is to include specific hypotheses as follows: <br /> <br />a. test flows do not significantly reduce densities of young- of-year <br />HBC; and (Fall 97 Test Flow T &C2) <br /> <br />b. test flows do not significantly affect/alter nearshore habitats used <br />by native fishes. (Fall 97 Test Flow T &C 2) <br /> <br />IN 3/4.4 Determine and identify surrogate native or non-native fishes for evaluation <br />of health factors for HBC and investigate trends in diseased fish. <br /> <br />IN 3/4.5 Develop a habitat suitability and availability index, which may include <br />backwaters and near shore habitat, using existing data for HBC. <br />Determine the effects of mainstem hydrology on the number of nearshore <br />rearing habitats, environmental conditions in these habitats, and their <br />successful utilization by HBC. (RPM I.C.iii) <br /> <br />IN 3/4.6 Evaluate impacts of sampling methods and recreation use (e.g., habitat <br />change, hooking mortality) on humpback chub populations. <br /> <br />Revised 6-10-98 <br />