Oregon Chub Investigations at Hospital Pond, 2000-2008; Information Reports 2009-07

Identification Information

Citation

Originator: Scheerer, P., M. Terwilliger and S. Jacobs

Publish Date: 2009

Online Link: None

BPA Project #:

Contact Information

Agency: Oregon Department of Fish and Wildlife

Name: Cedric Cooney

Job Position: Natural Resources Data and Systems Manager

Telephone: 503-947-6094

E-Mail Address: cedric.x.cooney@odfw.oregon.gov

Description

Abstract: Previous studies suggested relationships between Lookout Point Reservoir water elevations, Hospital Pond water levels and temperatures, and Oregon chub spawning and recruitment in the pond. Hospital Pond is fed by large cold springs and spawning only occurs when the reservoir is nearly full and floods the pond terrace. Changes in flow management in the Middle Fork Willamette River occurred in 2000, following the listing of Willamette spring chinook and winter steelhead, and resulted in changes in the frequency and magnitude of reservoir filling and the length of time the reservoir would remain full. The US Army Corps of Engineers modified the pond in an attempt to allow managers the ability to manage water levels and temperatures in Hospital Pond independently from reservoir levels. We found that these modifications were largely unsuccessful. We found that strong year-classes were infrequent and occurred in several, but not all of the years, when the reservoir filled. Our data also suggests that strong year-classes may limit the recruitment of the following year-class through density-dependent mechanisms, i.e. competition for food and space. If the reservoir continues to fill every few years, as it has for the last decade, we feel that that Oregon chub recruitment in Hospital Pond will be adequate to maintain a stable population into the future.

Purpose:

Time Period of Content: 2000-2008

Geographic Extent: Middle Fork Willamette River, Lookout Point Reservoir, Hospital Pond

Status: Final

Use Constraints:

Format: PDF File

Data Quality Information

Lineage-Source:

Data Information

No data information was supplied.

Entity and Attribute Information

Attributes Description: Field attribute information is available in the attached file(s).

Is a physical copy maintained for reference at Headquarters? No