9509

• UCREFRP Catalog Number: 9509
• Author: Hill, C. G.
• Title: Dynamics of Northern Pike Spawning and Nursery Habitat in the Yampa River, Colorado.
• USFW Year: 2004.
• USFW - Doc Type: Fort Collins, Colorado.
• Copyright Material: NO

Conclusions
· During 2002, the peak collection of adult spawning pike occurred in early April
when trapnets were first installed.
· Ideal water temperatures for northern pike spawning occurred in early April
during 2002 and 2003.
· At the nine backwaters surveyed there was very little change in the amount of
area available for spawning during early April of 2002 and 2003.
· The largest catch per unit effort (CPUE) and the largest total number of age-O
pike were found at the gravel pit pond investigated in this study.
· Few age-O pike were found in the backwater habitats investigated.
· The barriers installed during the winter did not adequately stay in place over the
winter, presumably because of disruption from the ice and rising water levels.
· The barrier installed during the spring did not adequately stay in place because of
either beaver or muskrat activity.
· The questionnaire sent to landowners along the Yampa River indicate that a
majority of them are willing to cooperate with the Colorado Division of Wildlife,
though some of these individuals may not necessarily have northern pike
spawning or nursery habitat on their property.

Only Objective I was addressed in this study. The results and conclusions
indicated exclusion of adult northern pike from spawning habitats using screening was
not effective. Therefore, expanded application and evaluation of this approach on a reach-
wide scale (Objectives 2 and 3) was not justified. Inadequate data was collected to
address Objective 4, though preliminary evidence suggesting small reservoirslponds may
be the primary production areas for age-O northern pike.

Management Considerations
· The use of barriers on riverine sites may be largely not appropriate or feasible
because of the apparent low numbers of northern pike being produced in the r.iver,
the difficulties associated with blocking adults from all possible sites, and private
land access issues.
· Management resources may be better spent on reducing pike recruitment in the
numerous off-channel lakes and ponds between Catamount Reservoir and Craig.
This should include further investigation of ponds and reservoirs as sources for
pike recruitment into the river.
· Blocking the connection of ponds and the outlet structures of reservoirs to the
river with nets or screens or complete removal of access to reduce overall
recruitment to the river population should be investigated.
· The role of Catamount and Stagecoach Reservoirs as sources of northern pike
(and perhaps Elkbead Reservoir) will sustain the problem until some reduction in
escapement is achieved.

12

I
I
I
I
I
I
I
I
I
I
I
I

J

I
I
I
I
I
I
I