Smith River Fisheries and Ecosystem Report

Appendix E Table of Contents Appendix C

Appendix D -- Additional data sources and abstracts

The Smith River Advisory Council

This is a consortium of groups and citizens that oversee and influence management of the Smith River watershed. The chairman is Jim Waldvogel, Sea Grant advisor for Del Norte County. Meetings are held monthly. The council includes timber industry representatives, environmentalists, fishery biologists, sport fishing groups, local government, and state and federal agencies. They make policy recommendations concerning the Smith River watershed (Jim Waldvogel personal communication 1997). Watershed coordinator is Joe Scriven.

 

Reedy, Gary D. 1995. Summer abundance and distribution of juvenile chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Oncorhynchus mykiss) in the Middle Fork Smith River, California. M.S. Thesis. Humboldt State University, Arcata, California.

Abundance of juvenile chinook salmon (Oncorhynchus tshawytscha) and yearling and older juvenile steelhead trout (Oncorhynchus mykiss) (steelhead >1) in the Middle Fork Smith River, California (sixth order stream with average summer flow of 8.5 cubic meters per second) was estimated on two occasions during the summer of 1993 and on three occasions during the summer of 1994 using visual estimates in sample habitat units. Habitat was classified with regard to subunits of pool, riffle, and run channel units (pool head, pool body, pool tail, in-pool run, riffle margin, riffle midchannel, run margin, run midchannel) that differed in velocity, turbulence, and depth. Aerial photographs were used to measure habitat areas. For pool bodies and riffle margins the use of habitat area in ratio estimation increased the precision of total abundance estimates by 21%-84%. Mean observable chinook density ranged from 0.0002 fish/square meter in riffle midchannels to 0.2085 fish/square meter in pool heads. Mean observable steelhead >1 density ranged from 0.0197 fish/square meter in pool bodies to 0.4716 fish/square meter in pool tails. For some habitat types, chinook abundance decreased within each summer, and steelhead >1 abundance increased between years. Analysis of the variation in repeat counts within a day indicated that measurement error was high in certain situations, but not generally higher than for visual estimates of fish abundance in smaller streams. High rates of emigration by chinook relative to steelhead >1 caused higher temporal variation in the abundance of chinook per unit. Recommendations are made for monitoring annual variation in abundance of juvenile chinook and steelhead >1 in the Middle Fork Smith River.

 

Scriven, Joseph D. In progress. Snorkel surveys for juvenile coho salmon in tributaries to the Smith River, California. M.S. Thesis. Humboldt State University, Arcata, California.

The potential listing of the coho salmon (Oncorhynchus kisutch) under the Endangered Species Act along the west coast of the United States has intensified efforts to document the current status of the various stocks of this species. This study ventured to create a species specific sampling methodology that will determine presence or absence of coho in small streams as well as provide population estimates of juvenile coho salmon. This methodology involves snorkel surveys only, since listing under the Endangered Species Act may prohibit sampling with more traditional means such as electrofishing and migrant trapping.

Exploratory dives in 17 tributaries to the Smith River in the summer of 1994 resulted in six streams with coho juveniles. Three streams were chosen to further study because they had the most coho: West Branch Mill Creek, Rowdy Creek, Patrick Creek. Reaches 2 km long were set up in each stream in which all habitats would be dove. West Branch Mill Creek had an estimated 7811 juvenile coho, Rowdy Creek had 489.5 coho, and Patrick Creek had 126.5 coho in their 2 km reaches. Habitat types were separated into three strata for analysis: riffles, runs, pools. Population estimates from subsampling percentages of each strata were calculated and combined to create an accurate and cost effective snorkel survey methodology. The best combination of sampling percentages for riffle, run, and pool strata were 5%, 33%, and 33% respectively.

Exploratory dives in 38 tributaries during summer 1995 resulted in 13 streams which contained juvenile coho salmon. Two streams, West Branch Mill Creek and Rowdy Creek, were chosen for further study because they had the most coho. The upper limit of coho was found in these two streams via exploratory diving, and the habitat unit was flagged. We proceeded with the subsampling scheme of 5-33-33% for riffles, runs, and pools respectively to estimate the coho population in the streams. West Branch Mill Creek had an estimated 6736 +/- 148 juvenile coho in 6.1 miles of stream; Rowdy Creek had 280 +/- 39 coho in 6.8 miles of stream.

Potentially, all the tributaries to the Smith River could be surveyed for coho juveniles in a single field season by a two person dive crew with a combination of exploratory diving and the 5-33-33% sampling protocol in a few streams. The shortcomings of the 1995 field season included electrofishing for 3 weeks to calibrate the dive crew, limited access to private property, and a field season cut short because school started in late August. If permission to access streams on private property was gained before the field season began, and the dive crew was not limited to a shortened field season, it would be feasible to complete a basin-wide survey of the Smith River in a single season.

 

Waldvogel, Jim. Sea Grant advisor for Del Norte County, Crescent City, California.

Beginning in the fall of 1980, Waldvogel began coducting annual surveys of chinook salmon spawning on the West Branch of Mill Creek, a tributary of the Smith River. This study, intended to last 20 years, seeks to determine the relative abundance of fall chinook spawning as habitat changes. Please see references to Waldvogel in the "Literature Cited" secttion which is listed in the table of contents.

 

Appendix C | Table of Contents | Appendix E

This document maintained by andybartson@hotmail.com.
Material Copyright © 1997 Andrew P. Bartson

This page is hosted by Get your own Free Home Page

1