BirdAnalyst
Species · BBS 2026 Release · 1966–2025

Steller's Jay Population Analysis

CorvidaeForest birdsCyanocitta stelleri

Steller's Jay has surged: up 115% on the route-weighted index since 1970.

+115%Since 1970TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
665RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Steller's Jay

The Steller's Jay (Cyanocitta stelleri) is a North American member of the Crows, Jays & Magpies (Corvidae). In this analysis it is grouped with the forest birds.

Size
10–27.5 in long (25–70 cm) — a medium to large songbird (typical for the family)
Habitat
Woodlands and forest edges, including wooded suburbs and parks.
Diet
Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
Range
Recorded on 665 Breeding Bird Survey routes across 13 states, most concentrated in the Northern Pacific Rainforest.
Family
Corvidae · Forest birds

Notable Steller's Jay TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Steller's Jay has surged in surveyed states: up 115% on the route-weighted index since 1970.

Steller's Jay Population Forecast

If the recent trend holds, Steller's Jay is projected to rise about 24% by 2030 — from 0.86 in 2025 to a central estimate of 1.1 (95% range 0.67–1.5). A 5-year backtest shows a typical error of ±43.7%, with 60% of held-out values landing inside the 95% band.

+24%Change by 2030TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
1.1Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.67–1.595% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±43.7%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Steller's Jay is projected to rise about 24% by 2030 — from 0.86 in 2025 to a central estimate of 1.1 (95% range 0.67–1.5). A 5-year backtest shows a typical error of ±43.7%, with 60% of held-out values landing inside the 95% band.19682030
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20261.10.651.4
20271.10.661.5
20281.10.661.5
20291.10.661.5
20301.10.671.5

Where the Steller's Jay Is Detected

BBS routes recording Steller's Jay, sized by most recent count.

Steller's Jay Population Trend by State

Steller's Jay population trend by state.
TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alaska-72%197333
Arizona+80%197025
California+5%1970164
Colorado-23%197088
Idaho-69%197234
Montana-83%197031
Nevada-30%19975
New Mexico+188%197026
Oregon+31%1970110
Texasinsufficient datan/a1
Utah-38%197142
Washington+93%197083
Wyoming-82%197923

Steller's Jay Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Steller's Jay population trend by Bird Conservation Region.
TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
BCR 4-80%19864
Northern Pacific Rainforest+37%1970158
Great Basin+64%197098
Northern Rockies-56%1970117
Sierra Nevada-31%197040
Southern Rockies / Colorado Plateau+17%1970149
Shortgrass Prairie-30%19994
Coastal California-22%197063
Sierra Madre Occidental+12%197023
Chihuahuan Desert+27%19785

Steller's Jay Conservation Status

Our route-weighted index shows it up about 115% since 1970.

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.