BirdAnalyst
Species · BCR 22 · BBS 2025 Release · 1966–2024

Red-winged Blackbird In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieGeneralists

Red-winged Blackbird in Eastern Tallgrass Prairie has fallen sharply: down 51% on the route-weighted index since 1968.

-51%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 →
278Routes In RegionSurvey 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 SignalsNotable 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 →

Red-winged Blackbird has fallen sharply in Eastern Tallgrass Prairie: down 51% on the route-weighted index since 1968.

Red-winged Blackbird In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Red-winged Blackbird in Eastern Tallgrass Prairie is projected to fall about 11% by 2029 — from 103 in 2024 to a central estimate of 92 (95% range 59–125). A 5-year backtest shows a typical error of ±2.8%, with 100% of held-out values landing inside the 95% band.

-11%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 →
92Projected 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 →
59–12595% 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 →
±2.8%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, Red-winged Blackbird in Eastern Tallgrass Prairie is projected to fall about 11% by 2029 — from 103 in 2024 to a central estimate of 92 (95% range 59–125). A 5-year backtest shows a typical error of ±2.8%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20259865132
20269764130
20279562128
20289461127
20299259125

Routes In Eastern Tallgrass Prairie

Routes recording Red-winged Blackbird in Eastern Tallgrass Prairie.
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 →
BeaucoupILLINOIS4322024
Cedar ValleyIOWA3611997
Davis CornerIOWA3562024
PontiacILLINOIS3342024
WilliamsburgIOWA3202023
HarveysburgOHIO3031996
WilmingtonOHIO3021996
BrooklynIOWA2962022
StreatorILLINOIS2742024
TiptonIOWA2682024
NewarkILLINOIS2672022
GeneseoILLINOIS2592021
BryantIOWA2552024
West LibertyIOWA2532024
PrairieburgIOWA2502024
Mt HamillIOWA2412024
GreenviewILLINOIS2262024
HarristownILLINOIS2192024
WarrenMISSOURI2161984
College SpgsIOWA2122004
BradburyILLINOIS2102024
HudsonIOWA2102022
WayneILLINOIS2092024
PawneeILLINOIS2002024
Kahoka2MISSOURI2002024

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