BirdAnalyst
Species · Iowa · BBS 2025 Release · 1966–2024

Cedar Waxwing Population Trend in Iowa

All statesGeneralists

Cedar Waxwing in Iowa has surged: up 644% on the route-weighted index since 1970.

+644%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 →
38Routes 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 →
54YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Cedar Waxwing 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 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 →

Cedar Waxwing has surged in Iowa: up 644% on the route-weighted index since 1970.

Cedar Waxwing Population Forecast in Iowa

If the recent trend holds, Cedar Waxwing in Iowa is projected to rise about 70% by 2029 — from 2.4 in 2024 to a central estimate of 4.0 (95% range 1.8–6.2). A 5-year backtest shows a typical error of ±69.8%, with 100% of held-out values landing inside the 95% band.

+70%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 →
4.0Projected 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 →
1.8–6.295% 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 →
±69.8%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, Cedar Waxwing in Iowa is projected to rise about 70% by 2029 — from 2.4 in 2024 to a central estimate of 4.0 (95% range 1.8–6.2). A 5-year backtest shows a typical error of ±69.8%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20253.71.56.0
20263.81.66.0
20273.91.66.1
20283.91.76.2
20294.01.86.2

Cedar Waxwing Survey Routes in Iowa

Routes recording Cedar Waxwing 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 →
Red Rock1120241969
Bryant920241975
Clare820131977
Prairieburg720181990
Gaza620042004
Mt Hamill520241968
Exline520241988
Washta520141994
Festina520241970
Rock Valley519971993
College Spgs420041989
Panther420241968
Neola419921992
Hudson420221970
Tipton420241993
Wales320181971
Maquoketa320241986
Kanawha320172017
Titonka319891986
College Spgs 2320232008
Melrose220241977
Bedford220182001
Brooklyn220191985
Washington220231975
Alice219951979

Cedar Waxwing Population Trend in Other States

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

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