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Species · Utah · BBS 2025 Release · 1966–2024

Blue-gray Gnatcatcher Population Trend in Utah

All statesForest birds

Blue-gray Gnatcatcher in Utah has surged: up 384% on the route-weighted index since 1985.

+384%Since 1985TrendPercent 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 →
80Routes 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 →
41YearsYears 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 UtahNotable 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 surged in Utah: up 384% on the route-weighted index since 1985.

Blue-gray Gnatcatcher Population Forecast in Utah

If the recent trend holds, Blue-gray Gnatcatcher in Utah is projected to rise about 23% by 2029 — from 2.7 in 2024 to a central estimate of 3.4 (95% range 2.1–4.7). A 5-year backtest shows a typical error of ±57.7%, with 60% of held-out values landing inside the 95% band.

+23%Change by 2029TrendPercent 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 →
3.4Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
2.1–4.795% 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 →
±57.7%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, Blue-gray Gnatcatcher in Utah is projected to rise about 23% by 2029 — from 2.7 in 2024 to a central estimate of 3.4 (95% range 2.1–4.7). A 5-year backtest shows a typical error of ±57.7%, with 60% of held-out values landing inside the 95% band.19732029
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 →
20253.21.94.5
20263.21.94.6
20273.32.04.6
20283.32.04.6
20293.42.14.7

Blue-gray Gnatcatcher Survey Routes in Utah

Routes recording Blue-gray Gnatcatcher in Utah.
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 →
Moquith Mtn1920241987
Shivwitz1820241992
La Sal 31420242007
La Sal 21220062003
Moab1020241986
Willow Creek920241986
Main Canyon920241988
Cleveland820241992
Cane Spr Des820101992
Newcastle720221997
Monticello720241998
Canyonlands720061991
Wellington 3620242012
Bonanza620151992
Jericho Junction620241997
Glen Canyon520241992
Arches Np520111989
Bryce Canyon520231990
Crawford Mts520232005
Desert View420241995
Boulder420191986
Jensen420241995
Leamington419971992
Castle Dale420231993
Lake Powell420091994

Blue-gray Gnatcatcher Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.