BirdAnalyst
Species · Idaho · BBS 2026 Release · 1966–2025

Blue-gray Gnatcatcher Population Trend in Idaho

All statesForest birds

Blue-gray Gnatcatcher in Idaho has risen sharply: up 52% on the route-weighted index since 1989.

+52%Since 1989TrendPercent 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 →
6Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
33YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Blue-gray Gnatcatcher Trends in IdahoNotable 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 →

Blue-gray Gnatcatcher has risen sharply in Idaho: up 52% on the route-weighted index since 1989.

Blue-gray Gnatcatcher Population Forecast in Idaho

If the recent trend holds, Blue-gray Gnatcatcher in Idaho is projected to fall about 68% by 2030 — from 0.23 in 2025 to a central estimate of 0.07 (95% range 0.00–0.19). A 5-year backtest shows a typical error of ±62.8%, with 80% of held-out values landing inside the 95% band.

-68%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 →
0.07Projected 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 →
0.00–0.1995% 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 →
±62.8%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, Blue-gray Gnatcatcher in Idaho is projected to fall about 68% by 2030 — from 0.23 in 2025 to a central estimate of 0.07 (95% range 0.00–0.19). A 5-year backtest shows a typical error of ±62.8%, with 80% of held-out values landing inside the 95% band.19792030
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 →
20260.080.000.19
20270.080.000.19
20280.070.000.19
20290.070.000.19
20300.070.000.19

Blue-gray Gnatcatcher Survey Routes in Idaho

Routes recording Blue-gray Gnatcatcher in Idaho.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Daniels Res420252025
Almo320251988
Pocatello320191979
Twin Buttes120101988
Kyle Canyon120251995
Magic Mtn120082008

Blue-gray Gnatcatcher Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.