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

Rock Pigeon Population Trend in Iowa

All statesGeneralists

Rock Pigeon in Iowa has fallen sharply: down 53% on the route-weighted index since 1969.

-53%Since 1969TrendPercent 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 →
39Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Rock Pigeon Trends in IowaNotable 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 declinecomputed 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 →

Rock Pigeon has fallen sharply in Iowa: down 53% on the route-weighted index since 1969.

Rock Pigeon Population Forecast in Iowa

If the recent trend holds, Rock Pigeon in Iowa is projected to fall about 63% by 2030 — from 7.4 in 2025 to a central estimate of 2.7 (95% range 0.00–9.0). A 5-year backtest shows a typical error of ±36.7%, with 100% of held-out values landing inside the 95% band.

-63%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 →
2.7Projected 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 →
0.00–9.095% 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 →
±36.7%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, Rock Pigeon in Iowa is projected to fall about 63% by 2030 — from 7.4 in 2025 to a central estimate of 2.7 (95% range 0.00–9.0). A 5-year backtest shows a typical error of ±36.7%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20263.90.0010
20273.60.009.9
20283.30.009.6
20293.00.009.3
20302.70.009.0

Rock Pigeon Survey Routes in Iowa

Routes recording Rock Pigeon in Iowa.
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 →
Gaza5520251969
Hudson2920251967
Rock Valley2520251968
Mccallsburg2120251996
Sioux City1520251968
Desmoines1419791968
Garner1419931971
Festina1220251968
Alice1019991972
Cedar Valley919971967
Davis Corner920251968
Clare820191967
Pierson820251968
Brooklyn620251967
Prairieburg620241971
Kanawha620251967
Zearing619951967
Tipton620251993
Lafayette620252003
Titonka520191968
Burchinal520251995
College Spgs 2520232006
Bryant420251967
Williamsburg420231969
Scranton420251967

Rock Pigeon Population Trend in Other States

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

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