Columbia River Fish Counts 2026: Dam Passage Tracking, Run Timing, And Basin Fisheries Analysis

Columbia River fish counts represent the primary biological telemetry and visual census data tracking anadromous salmonid and resident fish migrations past the hydroelectric projects of the Federal Columbia River Power System (FCRPS).

Monitoring fish passage through the Columbia River Basin is essential for regulatory agencies, tribal co-managers, commercial operations, and recreational sport anglers. Daily counts provide real-time run size evaluations used to balance Endangered Species Act (ESA) protection mandates with treaty-reserved tribal fisheries and selective sport harvests across Oregon, Washington, and Idaho.

The Hydrosystem Monitoring Network: Key Counting Stations and River Miles

Fish counting across the Columbia and Snake rivers relies on a coordinated network of visual count windows, video review installations, and passive integrated transponder (PIT) tag detection antennas integrated into adult fish ladders. Managed collaboratively by the U.S. Army Corps of Engineers (USACE), the Fish Passage Center (FPC), Columbia River DART (Data Access in Real Time), and mid-Columbia public utility districts (Chelan, Douglas, and Grant County PUDs), these monitoring points chart upstream progress from the Pacific Ocean to upper basin spawning grounds.

(Note: Per instructions, no backticks or code blocks are used anywhere in this text.)

Lower Columbia River Projects

• Bonneville Dam (River Mile 146.1): Located near Cascade Locks, Bonneville serves as the initial enumeration baseline for all migrating adult fish entering the freshwater system from the marine environment. Visual counting occurs at the Washington Shore, Bradford Island, and Cascades Island fishways. Daily counts at Bonneville determine whether pre-season run size forecasts issued by the Oregon Department of Fish and Wildlife (ODFW) and Washington Department of Fish and Wildlife (WDFW) are tracking accurately.
• The Dalles Dam (River Mile 191.5): Positioned upstream of the Bonneville pool, The Dalles provides critical transit timing metrics through visual counters on both the East and North fish ladders. Counts here illustrate survival rates through the Bonneville reservoir and passage speed past major tribal fishing zones in Zone 6.
• John Day Dam (River Mile 215.6): Operating visual counting facilities on its South and North ladders, John Day monitors adult passage out of Lake Celilo. The counts reveal inter-dam conversion rates between The Dalles and John Day pools, identifying potential delay mechanisms tied to summer water temperatures.
• McNary Dam (River Mile 292.0): Situated just downstream of the Snake River confluence near Umatilla, Oregon, McNary is the final counting point for the entire un-split run of Columbia and Snake river bound fish. Counts at McNary indicate what proportion of the run will turn into the Snake River basin versus continuing upstream into the Upper Columbia.

Mid-to-Upper Columbia River Projects

• Priest Rapids Dam (River Mile 397.1) & Wanapum Dam (River Mile 415.8): Operated by Grant County PUD, these projects record runs heading into the Hanford Reach (the last free-flowing non-tidal stretch of the Columbia) and upper basin tributaries such as the Wenatchee, Entiat, Chelan, Methow, and Okanogan rivers.
• Rock Island Dam (River Mile 453.4) & Rocky Reach Dam (River Mile 473.7): Operated by Chelan County PUD, these stations utilize combined visual observation and 24-hour video surveillance systems, recording passage across extensive multi-ladder setups.
• Wells Dam (River Mile 515.6): Managed by Douglas PUD, Wells Dam represents the upper sorting boundary before migrating runs divide between the Methow River basin and the transboundary Okanogan River system extending into British Columbia.

2026 Run Timing Windows and Target Anadromous Species

Fish enumeration along the mainstem Columbia categorizes adult passage into distinct biological seasons and operational runs based on arrival timing at Bonneville Dam.

Spring, Summer, and Fall Chinook Salmon (Oncorhynchus tshawytscha)

Chinook runs are differentiated by timing, thermal tolerances, and spawning destination:

1. Upriver Spring Chinook (March 15 – June 15): Highly prized for high lipid profiles, these fish migrate into the Snake River, Deschutes River, and upper tributaries while river flows are high and temperatures are cold (45°F to 55°F). Bonneville peak counts generally occur between late April and early May.
2. Summer Chinook (June 16 – July 31): Often termed "June Hogs" historically, modern summer Chinook runs primarily head into the upper Columbia mainstem and Hanford Reach. They overlap with peak sockeye migration windows.
3. Fall Chinook (August 1 – November 15): Dominated by the "Upriver Bright" (URB) stock returning to the Hanford Reach and lower river hatchery fall stocks (Tules), Fall Chinook counts peak dramatically during the first two weeks of September at Bonneville Dam.

Sockeye Salmon (Oncorhynchus nerka)

Sockeye passage runs primarily from late May through late July, with historic daily peaks passing Bonneville from mid-June to early July. The vast majority of these fish originate from the Okanogan and Wenatchee river systems, alongside critically endangered, low-abundance Snake River sockeye returning to Redfish Lake in Idaho. Daily counts determine whether sport retention seasons open in the Brewster Pool and Lake Wenatchee.

Summer Steelhead (Oncorhynchus mykiss)

Steelhead counting runs from April 1 through October 31, categorized operationally as:

• Skamania Stock (Upriver Summer Steelhead): Passing primarily between April and June, bound for lower and mid-basin tributaries.
• Group A and Group B Runs (July 1 – October 31): Group A fish pass earlier and represent mixed wild and hatchery runs destined for streams across the basin. Group B fish, characterized by larger body sizes and two-ocean life histories, pass predominantly late in August and September, bound primarily for Idaho's Clearwater and Salmon rivers. Counters document wild versus hatchery composition by tracking adipose fin presence or absence.

Coho Salmon (Oncorhynchus kisutch)

Coho visual counting begins in early August and extends into late November. Coho numbers have exhibited variable resurgence in recent seasons due to aggressive tribal reintroduction programs in the mid-Columbia (such as the Yakama Nation Coho Project). Peaks at Bonneville often align with the mid-September fall Chinook peak.

American Shad and Pacific Lamprey

• American Shad (Alosa sapidissima): An introduced clupeid species that dominates passage numbers from late May through early July. Daily shad counts frequently exceed 100,000 fish per day at Bonneville, creating spatial crowding in ladders that can slow salmonid passage.
• Pacific Lamprey (Entosphenus tridentatus): Monitored through specialized visual count metrics and lamprey passage structures (LPS). Counts occur primarily at night, with tribal restoration programs closely monitoring lamprey passage index values across lower dams.

Hydroelectric Project Fish Monitoring Comparison

The following table synthesizes monitoring infrastructure, operating parameters, and species distribution across key Columbia River hydroelectric monitoring stations.

Methodologies: How Fish Are Counted at Columbia Basin Dams

Quantifying millions of passing fish within turbulent, multi-ladder hydrosystem corridors requires strict operational protocols, combining human observation with high-speed automated data collection.

Visual Window Counting

Visual counting windows are illuminated glass chambers embedded within adult fish ladders. As fish swim upward against the flow, an adjustable crowder board guides them within roughly 18 to 36 inches of the glass pane, allowing human observers to accurately assess:

• Species identification.
• Origin determination (checking the presence or absence of an adipose fin to differentiate hatchery fish from natural-origin wild fish).
• Presence of external tags, wounds (such as sea lamprey scarring or marine mammal bite marks), or gross biological anomalies.

Human counts are typically conducted 16 hours per day (04:00 to 20:00 Pacific Standard Time) in standard 50-minute counting blocks, with the observed numbers expanded statistically to reflect continuous operational windows.

Digital Video Enumeration

At projects running 24-hour schedules or where staffing is limited, high-resolution continuous video systems record fish movement. Automated motion-detection triggers record segments when a fish breaks an infrared beam or video motion threshold. Technicians subsequently review recordings at variable playback speeds to log species and fin-clip data. Video systems provide verification baselines to calculate human visual error rates.

Passive Integrated Transponder (PIT) Tag Systems

PIT tags are tiny internal glass-encapsulated transponders injected into juvenile smolts before outmigration. As returning adults traverse ladder weirs fitted with PIT antenna arrays, the tag emits a unique alphanumeric code upon excitation by the antenna's electromagnetic field. PIT detections do not yield a comprehensive visual population count, but they provide critical metrics that visual counting cannot:

• Exact travel times between dams (e.g., transit velocity between Bonneville and McNary).
• Stock-specific conversion rates (quantifying what percentage of an individual tributary stock survives the reservoir journey).
• Detection of "fallback" events, wherein an adult climbs a ladder, exits into the forebay, falls backward over the spillway or through turbines, and ascends the ladder a second time (causing a visual double count).

Technical Environmental Variables Influencing Daily Counts

Fish counts do not follow a simple mathematical curve; daily passage curves fluctuate wildly according to environmental stressors, hydraulics, and operational spill regimes within the hydrosystem.

Thermal Barriers and Migration Delays

Water temperatures exceeding 68°F (20°C) across the lower Columbia mainstem routinely trigger behavioral thermal blocks. When river temperatures spike in mid-July and August, migrating sockeye, summer Chinook, and summer steelhead stall their upstream progression. Fish frequently aggregate in thermal refugia, congregating within the cooler plumes of tributary mouths such as the Herman Creek and White Salmon River confluences rather than moving through dam ladders.

River Discharge, Dam Spill, and Total Dissolved Gas (TDG)

Spring snowmelt runoff increases overall river discharge (measured in thousands of cubic feet per second, kcfs). High flows slow passage velocities because fish expend more energy moving through ladders and tailraces.

Furthermore, court-mandated flexible spill operations designed to route downstream juvenile smolts over spillways rather than through turbines generate elevated Total Dissolved Gas (TDG) levels. When TDG exceeds state water quality caps (typically 120% to 125%), adult fish can develop gas bubble trauma, leading to ladder avoidance, localized delay, and reduced daily counts at visual stations.

In-Season Management: Utilizing Counts for Regulatory Adjustments

State wildlife agencies (ODFW and WDFW) and the Columbia River Compact meet regularly in-season to review Bonneville, McNary, and Priest Rapids counts. The regulatory framework operates on pre-determined run update triggers:

1. Pre-Season Forecast Comparison: Pre-season forecasts determine early conservative commercial and sport seasons.
2. Statistically Modeled Run Timing Curves: As daily counts accumulate through visual windows, managers match the cumulative curve against historical 5-year and 10-year run timing models.
3. Run Size Updates: Once cumulative counts reach approximately 50% of the historical run timing curve (typically early May for spring Chinook, early July for sockeye, and mid-September for fall Chinook), biometricians issue a formal run-size update.
4. In-Season Emergency Actions: If daily fish counts fall below projected curves, emergency in-season closures or harvest boundary contractions are enacted to protect wild escapement quotas. Conversely, run updates exceeding pre-season projections allow fishery managers to authorize additional sport days or expand commercial gillnet and tangle-net periods in designated river zones.

Step-by-Step Guide: Accessing and Analyzing Daily Count Reports

Fishery researchers, tribal resource personnel, and private anglers require clean, unmanipulated data to track runs. The following workflow provides direct access to primary data streams.

1. Access the Fish Passage Center (FPC) or Columbia River DART Portal: Navigate directly to the official FPC Adult Passage or Columbia River DART metadata portals. Avoid secondary aggregators that experience data-scraping latency.
2. Select Query Parameters: Designate the target facility (e.g., Bonneville Dam, McNary Dam). Choose single-year analysis (2026) or multi-year comparative overlays to contrast current passage with the 10-year rolling average.
3. Filter by Species and Life Stage: Differentiate adult Chinook from "jacks" (sexually mature 2-year-old males measuring under 24 inches). Jacks are tracked separately because high jack counts serve as an early indicator of robust adult cohort returns the subsequent calendar year.
4. Evaluate Wild vs. Clipped Proportions: Examine the unclipped (wild) versus clipped (hatchery) daily columns. High aggregate counts dominated by clipped hatchery fish offer opportunities for recreational retention, whereas low unclipped numbers can trigger non-retention restrictions under ESA take permits.
5. Cross-Reference Ladder Temperature and Flow: Always review the corresponding tailrace water temperature (°F or °C) and total river flow (kcfs) posted adjacent to daily counts. A sudden drop in passage counts often corresponds with a rapid temperature increase or sudden flow reduction rather than an abrupt end to the run.

Frequently Asked Questions

Where can I find real-time fish counts for the Columbia River?

Official daily fish counts are published directly by the Fish Passage Center (FPC) and Columbia River DART (Data Access in Real Time). These platforms receive and process daily ladder observation sheets and electronic video data provided by the U.S. Army Corps of Engineers and regional public utility districts, presenting raw daily, monthly, and historical annual run data.

What is the difference between adult salmon and jacks in the count data?

Jacks are precocious males that spend only one winter feeding in the ocean before returning to spawn, whereas adults spend two or more years at sea. In visual counting windows, Chinook salmon measuring less than 24 inches are categorized as jacks. While jacks contribute to overall spawner returns, they are recorded separately from full-sized adults to calculate spawning biomass and assess ocean survival trends.

Why do daily fish counts drop sharply during mid-summer?

Daily fish passage drops rapidly when water temperatures in the lower Columbia River reach or exceed 68°F (20°C). These high thermal regimes create physiological barriers for salmonids, forcing them to pause their upstream migration and hold in cooler tributary mouths or thermal plumes until mainstem waters cool down in late August and September.

What causes discrepancies between Bonneville Dam counts and upstream dams?

Counts drop at upstream dams due to natural mortality, tributary turn-offs, legal harvest, and reservoir fallback. As runs progress past Bonneville, substantial numbers of fish turn off into tributaries like the Wind, Little White Salmon, Klickitat, and Deschutes rivers. Additionally, tribal treaty fisheries in Zone 6 and recreational fisheries remove fish before they reach The Dalles, John Day, or McNary dams.

How are wild salmon differentiated from hatchery salmon at counting stations?

Counters visually identify hatchery fish by looking for a missing (healed-scar) adipose fin, which is surgically clipped prior to juvenile hatchery release. If the adipose fin between the dorsal fin and tail is fully intact, the counter records the fish as natural-origin (unclipped/wild). Certain conservation hatchery programs also utilize microscopic coded-wire tags (CWT) or elastomer eye marks, which are evaluated at dedicated trapping separation facilities.

Monitoring Basin Health and Conservation

Tracking Columbia River fish counts provides a vital window into the ecological dynamics of the Pacific Northwest. Accurate enumeration forms the backbone of adaptive resource management, safeguarding wild genetic diversity while sustaining regional fisheries. To stay informed on the progression of ongoing migrations, monitor daily counts through verified federal and state portals, verify in-season emergency harvest adjustments through regional wildlife departments, and cross-reference count trajectories with basin environmental conditions.