BirdAnalyst
Species · BCR 22 · BBS 2026 Release · 1966–2025

Mallard In Eastern Tallgrass Prairie

All regionsEastern Tallgrass PrairieWaterfowl

Mallard in Eastern Tallgrass Prairie has surged: up 233% on the route-weighted index since 1968.

+233%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 →
234Routes 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 →
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 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 →

Mallard has surged in Eastern Tallgrass Prairie: up 233% on the route-weighted index since 1968.

Mallard In Eastern Tallgrass Prairie Population Forecast

If the recent trend holds, Mallard in Eastern Tallgrass Prairie is projected to rise about 79% by 2030 — from 0.85 in 2025 to a central estimate of 1.5 (95% range 0.36–2.7). A 5-year backtest shows a typical error of ±139.4%, with 60% of held-out values landing inside the 95% band.

+79%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 →
1.5Projected 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 →
0.36–2.795% 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 →
±139.4%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, Mallard in Eastern Tallgrass Prairie is projected to rise about 79% by 2030 — from 0.85 in 2025 to a central estimate of 1.5 (95% range 0.36–2.7). A 5-year backtest shows a typical error of ±139.4%, with 60% 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 →
20261.50.352.7
20271.50.352.7
20281.50.362.7
20291.50.362.7
20301.50.362.7

Routes In Eastern Tallgrass Prairie

Routes recording Mallard 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 →
YorkvilleILLINOIS1202018
PutnamILLINOIS652017
New LenoxILLINOIS572019
NewportOHIO561994
LakevilleMINNESOTA342025
SherburnvillILLINOIS172022
DecaturINDIANA172025
MuncieINDIANA161997
GaryINDIANA151999
WayneILLINOIS142025
MarionOHIO142023
HarveysburgOHIO131996
MinonkILLINOIS122024
TrentonMISSOURI112021
KeithsburgILLINOIS92019
MontpelierINDIANA92019
PlainfieldINDIANA91999
ExlineIOWA92014
TecumsehOHIO81982
Kankakee SandsINDIANA72025
Kahoka2MISSOURI72024
BotkinsOHIO72019
Troy GroveILLINOIS62019
UnionILLINOIS62017
FowlerINDIANA62019

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