Hult Reservoir Fish Species Composition, Size and Relative Abundance 2017

Identification Information

Citation

Originator: Romer, Jeremy D., Fred R. Monzyk, Erik J. Suring and Thomas A. Friesen

Publish Date: February 2018

Online Link: None

BPA Project #:

Contact Information

Agency: Oregon Department of Fish and Wildlife

Name: Jeremy Romer

Job Position: Assistant District Fish Biologist

Telephone: 541-726-3515 X34

E-Mail Address: jeremy.d.romer@odfw.oregon.gov

Description

Abstract: Seven species of fish were encountered in Hult Reservoir in 2017: largemouth bass (Micropterus salmoides), cutthroat trout (Oncorhynchus clarkii), rainbow trout/winter steelhead (Oncorhynchus mykiss), bluegill (Lepomis macrochirus), reticulate sculpin (Cottus perplexus), brown bullhead (Ameiurus nebulosus) and western brook lamprey (Lampetra richardsoni). The most abundant fish observed were largemouth bass and bluegill in the summer and fall, and cutthroat in the winter. Cutthroat trout were much more prevalent in the fall and winter sampling than in the summer. Presumably, most cutthroat trout moved up into the tributaries to seek thermal refuge during the summer months and returned to the reservoir once the temperatures were more conducive to growth and survival. However, some of them likely moved downstream, were preyed upon, or perished from the high summer temperatures and low dissolved oxygen conditions in the reservoir in summer. Under current conditions, high surface temperature (>20?), bass predation, and hypoxic dissolved oxygen levels below four meters of depth show that reservoir conditions are inhospitable for juvenile salmonids in the summer. Currently there are well established fisheries for both cutthroat trout (spring, fall, winter) and largemouth bass (summer) in the reservoir, and we talked to several anglers who target each of these species. Habitat segregation in the summer between the salmonids who move out of the reservoir and the warm-water fish that remain and spawn in the reservoir results in a diversified year-round angling opportunity. There were no coho salmon (juvenile or adult) observed in Hult Reservoir in 2017, but adult coho salmon were observed spawning just downstream of the dam. This observation verifies that a proportion of the adult coho attempting to ascend the ladder at Lake Creek Falls are successful and continue migration upstream to the vicinity of Hult Reservoir. It may be possible to keep the current fishery in Hult Reservoir as it stands and still increase coho production in the system by improving adult passage at Lake Creek Falls, and possibly at Hult Dam.

Purpose: The goal of this project was to provide information for the Bureau of Land Management (BLM) and Oregon Department of Fish and Wildlife (ODFW) regarding the current species composition, size, length frequencies and relative abundance of fish occupying Hult Reservoir, a small reservoir owned by BLM in the Siuslaw Basin on upper Lake Creek near the town of Horton, Oregon. Understanding the existing species composition, native fish habitat utilization, relative abundance of native and non-native fish and characterization of current fishing opportunities will allow the agencies to better promote, advertise, and enhance the fishery for the public through targeted management activities. Specific objectives of this project were to: 1) collect information about the current fish species composition, size, and relative abundance of fish in the reservoir, particularly presence or absence of juvenile coho salmon, 2) provide a brief history of the site for reference, and 3) research and assimilate any previous data available for historical context.

Time Period of Content: 2017

Geographic Extent: Hult Reservoir, Siuslaw Basin, near the town of Horton

Status: Final

Use Constraints:

Format: pdf

Data Quality Information

Lineage-Source: Final Report from ODFW to fulfill a BLM contract

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