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

Ring-billed Gull In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieWetland birds

Ring-billed Gull in Eastern Tallgrass Prairie has surged: up 487% on the route-weighted index since 1979.

+487%Since 1979TrendPercent 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 →
37Routes 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 →
47YearsYears 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 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 →

Ring-billed Gull has surged in Eastern Tallgrass Prairie: up 486% on the route-weighted index since 1979.

Forecast

If the recent trend holds, Ring-billed Gull in Eastern Tallgrass Prairie is projected to rise about 233% by 2029 — from 0.69 in 2024 to a central estimate of 2.3 (95% range 0.00–5.0). A 5-year backtest shows a typical error of ±315.6%, with 100% of held-out values landing inside the 95% band.

+233%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 →
2.3Projected 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 →
0.00–5.095% 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 →
±315.6%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, Ring-billed Gull in Eastern Tallgrass Prairie is projected to rise about 233% by 2029 — from 0.69 in 2024 to a central estimate of 2.3 (95% range 0.00–5.0). A 5-year backtest shows a typical error of ±315.6%, with 100% of held-out values landing inside the 95% band.19772029
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 →
20252.20.004.9
20262.20.004.9
20272.30.005.0
20282.30.005.0
20292.30.005.0

Routes In Eastern Tallgrass Prairie

Routes recording Ring-billed Gull 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 →
PortageINDIANA2212004
GaryINDIANA2151999
Portage 2INDIANA692024
ItascaILLINOIS522024
Terre HauteILLINOIS332013
NorwalkOHIO122010
Crown PointINDIANA92019
YorkvilleILLINOIS82019
GeneseoILLINOIS61998
New LenoxILLINOIS52017
Rock CreekKANSAS52003
SherburnvillILLINOIS42023
BarringtonILLINOIS32011
HebronINDIANA32013
SheffieldILLINOIS21991
WayneILLINOIS22019
MinonkILLINOIS21998
PawneeILLINOIS21994
SenecaILLINOIS22013
Le RoyILLINOIS22010
Kankakee SandsINDIANA22015
MelroseIOWA22000
W CarrolltonOHIO22014
ClarksdaleILLINOIS11988
FloraILLINOIS11996

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