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Species · Utah · BBS 2026 Release · 1966–2025

Cassin's Finch Population Trend in Utah

All statesForest birds

Cassin's Finch in Utah has surged: up 150% on the route-weighted index since 1970.

+150%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 →
52Routes 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 →
50YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Cassin's Finch 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 →

Cassin's Finch has surged in Utah: up 150% on the route-weighted index since 1970.

Cassin's Finch Population Forecast in Utah

If the recent trend holds, Cassin's Finch in Utah is projected to fall about 12% by 2030 — from 1.4 in 2025 to a central estimate of 1.2 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±40.2%, with 100% of held-out values landing inside the 95% band.

-12%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 →
1.2Projected 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 →
0.00–2.595% 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 →
±40.2%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, Cassin's Finch in Utah is projected to fall about 12% by 2030 — from 1.4 in 2025 to a central estimate of 1.2 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±40.2%, with 100% 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 →
20261.20.002.5
20271.20.002.5
20281.20.002.5
20291.20.002.5
20301.20.002.5

Cassin's Finch Survey Routes in Utah

Routes recording Cassin's Finch 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 →
Grizzly Rdge1820251986
Red Spur Mtn.1520231997
Uintah Nf1519941987
Beck1419871969
Castleton1219771977
Soapstone1120251992
Bryce Canyon920251990
Heber Mtn.920251996
Navajo Lake820251970
Beaver620251968
Canyon Rims620182001
Wasatch Nf620241988
Notom619891989
Richfield520191994
Gooseberry520251994
Book Ridge420062003
Lost Cr. Res420161995
La Sal 2420062003
Dixie Nf420251993
Ferron420252000
Bonanza420051996
Altonah320251974
Saleratus Cr319951995
Skyline Driv320251986
Hanna320151997

Cassin's Finch Population Trend in Other States

arizonacaliforniacoloradoidahomontananevadanew-mexicooregonsouth-dakotawashingtonwyoming

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