Chinook Salmon Adult Abundance Monitoring Paul Kucera and Dave Faurot Nez Perce Tribe Department of Fisheries Resources Management BPA Project

Goal: Accurately assess the spring and summer chinook salmon spawning migration in the Secesh River and Lake Creek on an annual basis

Objectives: Accurately determine adult spring and summer chinook salmon escapement into the Secesh River and Lake Creek drainages on an annual basis Determine the timing of adult spring and summer chinook salmon spawning migration into the Secesh River and Lake Creek Compare redd count expansion data with underwater video determined abundance

Fisheries Management Needs for Snake River Basin Chinook Salmon Tributary Specific Knowledge Population Status (Hatchery and Natural) Adult Abundance Population Growth Rate Spatial Distribution Genetic Stock Structure

Need for Adult Abundance Information Population Status Monitoring Recovery Status (ESA) - NMFS (2000), McElhaney et al. (2000), NMFS (2002), Conservation Status - Reed and Blaustein (1997), Botkin et al. (2000), Mundy (1999), Foose et al. (1995),

Figure 1. Secesh River drainage.

Lake Creek Video Fish Counting Station Flow

Monitoring and Evaluation Plan: Criteria for determining when impacts associated with the structure are significant –Fish Impedance –Spawner Displacement Guidelines for corrective action Plan implementation schedule

Lake Creek Adult Salmon Abundance

Fish Per Redd Numbers LOCATION GROUPFISH/REDD Lake Creek 1998 NPT 1.02 Lake Creek 1999 NPT 3.58 Lake Creek 2001 NPT 2.07 Lake Creek 2002 NPT 2.05 Lake Creek 2003 NPT 1.99 Imnaha River ODFW Lookingglass Creek ODFW South Fork SR PATH 2.31 South Fork SR ISS 3.2

n= Lake Creek Salmon Migration Timing

Adult Salmon Movement

Abundance Data Purpose is to Provide Population Census Population Estimate

Idaho Chinook Salmon Redd Counts Purpose is to provide Index of Relative Abundance Trend Information Are one time index area counts conducted after the peak of spawning

Adult Salmon Abundance versus Redd Count Expansion Data

Limitations of Redd Counts: Redd counts have unquantified sources of measurement error Index redd counts conducted by the IDFG are used for trend information, not escapement estimates (S. Kiefer et al. 1996)

Limitations in Redd Count Expansions Redd Count Measurement Error Fish Per Redd Number Survey Area (Index vs. Extensive) Prespawning Mortality Sex Composition Age Structure Sources of Uncertainty

Acoustic Imaging Camera (DIDSON) [DIDSON = Dual frequency IDentification SONar]

Acoustic Imaging Camera (DIDSON)

Validation Underwater Video

DIDSON Validation n=10n=20n=45n=17n=37n=125n=54n=50n=75

Summary Adult salmon spawner abundance in Lake Creek ranged from 52 to 697 fish Salmon spawner migration timing ranged from June 9 to September 6 Fish per redd numbers were variable, ranging from 1.02 to 3.58 (including jacks) Redd count expansion abundance estimates were highly variable, are not consistently biased, and have unquantified sources of error Redd count expansion techniques are not a viable method in RM&E study designs to address abundance based Biological Opinion Tier 2 or Tier 3 questions

Summary Redd count expansion techniques are not a viable method for measurement of NMFS interim salmon abundance targets Acoustic imaging camera (DIDSON) was installed on the Secesh River in 2004 to estimate adult abundance Preliminary independent validation indicated that DIDSON identified 100% of all salmon targets

Adult Salmon Abundance versus Redd Count Expansion Data Johnson Creek