assessment of bull trout populations in the yakima river watershed

Assessment of Bull Trout Assessment of Bull Trout Populations in the Yakima Populations in the Yakima

River WatershedRiver Watershed

BackgroundBackground

Bull trout listed as “threatened” under ESA on June 10, 1998.

Listed for Columbia & Klamath River DPS.

USFWS recognized distinct bull trout populations in the Yakima River sub-basin.

Current PopulationsCurrent Populations

WDFW Salmonid Stock Inventory Report (1998) indicated 9 distinct bull trout populations in the Yakima sub-basin.

Current data suggests a minimum of 13 spawning populations

Current PopulationsCurrent Populations

7 populations isolated in upper basin reservoirs.

Minimum of 6 fluvial populations in the Yakima River system.

Redd count range: 4 redds for the weakest 233 redds for the healthiest.

ThreatsThreats

Isolation by dams, water withdrawals, de-watered streams; water quality problems associated with agriculture, forestry, grazing, roads, mining; over harvest, poaching, non-native species, residential and commercial development activities.

GoalGoal

Recover bull trout in the Mid Columbia Recovery Unit.

This proposal was tailored to compliment the NWPPC’s 2000 Fish & Wildlife program, the Yakima Sub-basin Plan and the Mid Columbia Recovery Plan.

Critical Information GapsCritical Information Gaps

Connections between populations in the fluvial system.

Lack of information in Cle Elum Lake drainage.

Genetic composition.Movement (migration) patterns.Adult summer / winter areas.

Critical Information GapsCritical Information Gaps

Juvenile rearing & downstream distribution.Identification & quantification of habitat.Distribution (presence/absence).Abundance.Spawning areas (new areas, refine current

indexes).

Presence /Absence SurveysPresence /Absence Surveys

AFS Protocol procedures for detecting bull trout (Peterson et al. 2001).

Backpack electro-fishing in small stream environments (NMFS Guidelines).

Population AbundancePopulation Abundance

Snorkel surveys to locate staging areas.

Refine or establish spawning index areas.

Extrapolate abundance from redd counts.

Mark-recapture estimates.

Radio Telemetry StudiesRadio Telemetry Studies

Trap post spawned bull trout.Intercept bulls in main stem areas. Radio tag. Monitor migration / movement patterns.Determine summer/wintering areas, pre-

spawn staging areas & fidelity to spawning tributaries.

Juvenile Distribution StudiesJuvenile Distribution Studies

Determine downstream distribution of early rearing juvenile bull trout via snorkeling procedures.

Migrant (smolt) screw traps on larger tributaries to monitor movement.

Habitat Correlations Habitat Correlations

Measure & correlate habitat & biotic attributes with the occurrence of juvenile bull trout (Dunham et al 2000).

Measure habitat in spawning areas.

Apply to other areas to determine potential spawning and rearing habitat.

Determine Genetic Determine Genetic CompositionComposition

Collect tissue samples for micro-satellite DNA genetic analysis.

Tissue samples taken in conjunction with other fish handling activities.

Determine Limiting Factors Determine Limiting Factors

Data from this study.Current data.Historical or archived information.Literature searches.Compare life history requirements to

measured conditions.Incorporate limiting factors into existing

databases.

Determine & Implement Determine & Implement Management ActionsManagement Actions

Synthesize data & limiting factors.Generate management recommendations.BPA Reports & other publications.Information to MCRUT & others working

to recover bull trout in the Columbia Basin.Assist MCRUT with bull trout recovery.

Benefits Benefits “Columbia Connection” “Columbia Connection”

Data on distribution, abundance, habitat and genetics will contribute to management, restoration and preservation of bull trout in the Columbia Basin.

Augments other assessment and recovery efforts in the Columbia Gorge & in the upper Columbia/Wenatchee system.

Benefits Benefits “Columbia Connection” “Columbia Connection”

Consistent with and supports the vision of the NWPPC’s 2000 Columbia River Basin Fish & Wildlife Program, the Yakima Sub-basin Plan, and the Mid Columbia Bull Trout Recovery Plan.

Benefits Benefits “Columbia Connection” “Columbia Connection”

Objectives designed to facilitate the 2000 Program directives by resolving key uncertainties associated with resident fish losses.

Objectives can be measured and quantified.

Information vital for implementing recovery in the Yakima arm of the Columbia basin.