My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
8170
CWCB
>
UCREFRP
>
Public
>
8170
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
7/14/2009 5:02:33 PM
Creation date
5/22/2009 7:40:02 PM
Metadata
Fields
Template:
UCREFRP
UCREFRP Catalog Number
8170
Author
Trammell, M. A., K. D. Christopherson, C. L. Rakowski, J. C. Schmidt, K. S. Day, C. Crosby and T. E. Chart.
Title
Flaming Gorge Studies
USFW Year
1999.
USFW - Doc Type
Assessment of Colorado Pikeminnow Nursery Habitat in the Green River.
Copyright Material
NO
Jump to thumbnail
< previous set
next set >
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
312
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
Show annotations
View images
View plain text
<br /> <br /> <br />1 <br />C <br /> <br /> <br /> <br />1 <br />1 <br /> <br />L <br />1 <br /> <br /> <br /> <br /> <br /> <br />advantage of the positive aspects of both high and moderate flow scenarios, while avoiding <br />extremely low flows which favor nonnatives over the Colorado pikeminnow. <br />- Management of nonnative fishes will continue to be a problem. Although often suggested as <br />the best method of control, high spring flows did not appeaz to consistently negatively impact <br />nonnatives. Caze must be taken not to avoid managing exclusively for Colorado pikeminnow <br />to the detriment of other native fish or benefit of nonnative fish. <br />- Base flows (summer, fall): Maintain summer and fall flow levels below 140 m3/s (5000 cfs), <br />to maximize habitat availability. <br />- The maximum area of available nursery habitat may occur at discharges much lower or much <br />higher than the recommended base flow; the target summer dischazge should vary annually <br />and reflect changes in channel topography. <br />- Base flows (Winter): dischazges should be reduced. Current winter dischazges, increased by <br />Flaming Gorge Dam releases, overtop many low elevation bazs. <br />Changes to Standardized Monitoring Program <br />- No major changes to the ISMP sampling procedures are recommended. However, some <br />possible adjustments to the ISMP sampling aze presented: <br />1. Since higher turbidity was positively correlated with presence of Colorado pikeminnow, <br />and pikeminnow were commonly found in backwaters of less than 0.3 m depth, the <br />minimum depth requirement should be dropped to 0.2 - 0.25 m in turbid backwaters. <br />Turbidity can be visually assessed using the subjective scale used in reports B and C <br />without disturbing the fish community and biasing the sample. <br />2. The ISMP protocols call for fish community information to be taken from only one of <br />four seine hauls in each 5-mile subreach. This could be easily expanded to one seine <br />haul per backwater to provide more information on the fish community. This additional <br />data could help resolve remaining uncertainties regazding the effect of environmental <br />variables on nonnative fish densities, and fish community effects on Colorado <br />pikeminnow as well as other native fish. <br />- For depletion efforts, such as a nonnative cyprinid control program, a minimum of three <br />passes should be made in each habitat to ensure adequate fish removal. <br />- In order to link the ISMP catch rates with the total year class strength of Colorado <br />pikeminnow, population estimates should be done for several years on several selected <br />backwaters, using acapture-removal technique. <br />xx <br /> <br />
The URL can be used to link to this page
Your browser does not support the video tag.