Chinook Salmon Adult Abundance Monitoring

Paul Kucera and Dave Faurot

Nez Perce Tribe Department of

Fisheries Resources Management

BPA Project 199703000

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),

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

Year

1997 1998 1999 2000 2001 2002 2003 2004

Abu

ndan

ce

0

200

400

600

800

5286

324

697

410

490

Fish Per Redd Numbers

LOCATION GROUP FISH/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 1.64-6.80

Lookingglass Creek ODFW 2.3-4.5

South Fork SR PATH 2.31

South Fork SR ISS 3.2

n=Lake Creek Salmon Migration Timing

1998

-10

10

Nu

mb

er o

f F

ish

2001

-200

204060

6/1 6/15 6/29 7/13 7/27 8/10 8/24 9/7

Date

Num

ber

of F

ish

Adult Salmon Movement

-20

0

20

40

60

26-Jun

10-Jul

24-Jul

7-Aug

21-Aug

Date

Num

ber

of F

ish

Net Movement Total Movement

2002

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 afterthe peak of spawning

-100

-50

0

50

100

150

0 200 400 600 800

Video Abundance

% D

iffe

ren

ce B

etw

een

A

bu

nd

ance

an

d R

edd

E

xpan

sio

ns

Peak Index ReddExpansion

Multiple Pass IndexRedd Expansion

Extensive Area ReddExpansion

Adult Salmon Abundanceversus

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

Validation Underwater Video

DIDSON Validation

0102030405060708090

100

Aug.1

Aug.2

Aug.3

Aug.4

Aug.5

Aug.6

Aug.7

Aug.8

Aug.9

Date

Per

cen

t O

bse

rved

DIDSON Optical Cameran=10 n=20 n=45 n=17 n=37 n=125 n=54 n=50 n=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