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Species · Illinois · BBS 2026 Release · 1966–2025

Downy Woodpecker Population Trend in Illinois

All statesForest birds

Downy Woodpecker in Illinois has surged: up 88% on the route-weighted index since 1968.

+88%Since 1968TrendPercent 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 →
105Routes 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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Downy Woodpecker Trends in IllinoisNotable 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 →

Downy Woodpecker has surged in Illinois: up 88% on the route-weighted index since 1968.

Downy Woodpecker Population Forecast in Illinois

If the recent trend holds, Downy Woodpecker in Illinois is projected to stay roughly flat through 2030, near 2.1 (95% range 1.5–2.7). A 5-year backtest shows a typical error of ±13.1%, with 80% of held-out values landing inside the 95% band.

+8%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 →
2.1Projected 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 →
1.5–2.795% 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 →
±13.1%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, Downy Woodpecker in Illinois is projected to stay roughly flat through 2030, near 2.1 (95% range 1.5–2.7). A 5-year backtest shows a typical error of ±13.1%, with 80% of held-out values landing inside the 95% band.19662030
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 →
20262.11.52.7
20272.11.52.7
20282.11.52.7
20292.11.52.7
20302.11.52.7

Downy Woodpecker Survey Routes in Illinois

Routes recording Downy Woodpecker in Illinois.
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 →
Bremen1020251969
Beaverdam Lk820231970
Sheffield720241966
Monica720161974
Athensville720251971
St Morgan720221967
Mill Creek620251966
Wayne620251967
Athens620251995
Stillwell520251971
Chandlervill520241971
Mt Vernon520251971
Birds520241977
Pulaski520251971
Delwood520251970
Cave In Rock520241993
Union520172001
Geneseo420251967
New Lenox420191969
Gulfport420251971
Deer Creek420241966
Melrose419991973
Camp Point420251993
Duncan Mills420251993
York420251993

Downy Woodpecker Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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