9689

• UCREFRP Catalog Number: 9689
• Author: Recovery Implementation Program.
• Title: Recovery Implementation Program For Endangered Fish Species In The Upper Colorado And San Juan River Basins - 27th Annual Recovery Program Researchers Meeting Program.
• USFW Year: 2006.
• USFW - Doc Type: Moab, UT.
• Copyright Material: NO

20. Estimating sources of northern pike (Esox lucius) recruitment in the Yampa
River, using otolith microchemistry

Authors: DANA L. WINKELMAN and RYAN FITZPATRICK, Colorado Cooperative
Fish and Wildlife Research Unit, Colorado State University, 201 NK Wagar Bldg., Fort
Collins, CO 80523, P 970-491-1414, F 970-491-1413, [e-mail]

Abstract: Northern pike (Esox lucius) are an exotic predator in the Yampa River and
little is known about their movements or sources of recruitment. It is thought that
northern pike spawn in the river channel but it also likely that they spawn in off-channel
ponds and reservoirs. The relative contribution of these areas to young-of-year northern
pike recruitment is unknown. Weare using otolith microchemistry to develop elemental
signatures to estimate relative levels of recruitment from various potential sources in the
Yampa River. Initial results indicate that elemental signatures can be used to delineate
recruitment sources in the Yampa River system. We used a discriminant function to
classify northern pike based on elemental signatures. Overall, reclassification rates
ranged from 56-100%. Elkhead, Catamount, and Stagecoach reservoirs are thought to be
important potential recruitment sources had high reclassification rates (100%, 90%, and
71.4% respectively), indicating that we should be able to identify pike coming from these
sources. Ponds had somewhat lower reclassification rates, making estimates of
provenance more difficult; however, we can still delineate among many of these sources.
Elemental analyses appear to be an effective tool to identify major sources of recruitment
and could help guide the management of northern pike in the Yampa River.

21. Cibo)a High Levee Pond and Beyond: A Native Fish Sanctuary Initiative.

Authors: GORDON MUELLER and JEANETTE CARPENTER, USGS.

Abstract: Bonytail and razorback sucker sustained a natural fish community in Cibola
High Levee Pond for nearly 12 years. The absence of nonnative predators allowed
natural recruitment. In 2002, the 5 acre pond contained multiple year classes and more
than 1,000 razorback sucker and 10,000 bonytail. Largemouth bass was first noticed in
2003 and its suspected they were illegally introduced by anglers. Netting and
electrofishing proved ineffective in their removal. Those bass spawned in 2004,
producing thousands of young. By the fall of2005, largemouth bass comprised 85% of
the total fish community. The native component was reduced to large (45+cm)
razorback adults (15%) and a few (<1 %) large (30+cm) bonytail within 18 months.
Based on the initial success at Cibola High Levee Pond, the Bureau of
Reclamation funded USGS to test Minckley's Native Fish Conservation Plan. The
program is forming a coalition of land management partners to develop a native fish
sanctuary system using existing ponds. The goal is to establish a minimum of ten small
native fish sanctuaries where fish can reproduce naturally. It is hoped through the active
management and research opportunities provided by these small faculties, we will gain
the knowledge and expertise necessary to expand this approach on a larger scale.

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