BirdAnalyst
Species · BCR 37 · BBS 2025 Release · 1966–2024

Brown-headed Cowbird In Gulf Coastal Prairie

All regionsGulf Coastal PrairieGeneralists

Brown-headed Cowbird in Gulf Coastal Prairie has held roughly steady: up 4% on the route-weighted index since 1969.

+4%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 →
48Routes 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 →
57YearsYears 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 →

No notable trend signals for Brown-headed Cowbird in Gulf Coastal Prairie. See the full index history below.

Forecast

If the recent trend holds, Brown-headed Cowbird in Gulf Coastal Prairie is projected to stay roughly flat through 2029, near 12 (95% range 5.6–19). A 5-year backtest shows a typical error of ±25.7%, with 100% of held-out values landing inside the 95% band.

-9%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 →
12Projected 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 →
5.6–1995% 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 →
±25.7%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, Brown-headed Cowbird in Gulf Coastal Prairie is projected to stay roughly flat through 2029, near 12 (95% range 5.6–19). A 5-year backtest shows a typical error of ±25.7%, with 100% of held-out values landing inside the 95% band.19672029
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 →
2025125.319
2026125.419
2027125.519
2028125.519
2029125.619

Routes In Gulf Coastal Prairie

Routes recording Brown-headed Cowbird in Gulf Coastal 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 →
WoodlawnLOUISIANA1592021
Forked Island 2LOUISIANA642011
Oyster LakeTEXAS582024
ChinquapinTEXAS462024
WinnieTEXAS342024
Ltl Chenier 2LOUISIANA322011
Sabine NwrLOUISIANA282002
Goliad PrairieTEXAS282016
McfaddinTEXAS252016
Loyola BeachTEXAS232009
CreoleLOUISIANA221987
IndianolaTEXAS192024
KatyTEXAS192024
Loyola Beach 2TEXAS192024
VanderbiltTEXAS171976
Hinkles FerTEXAS142024
Ville PlatteLOUISIANA132019
Grand IsleLOUISIANA122019
Ltl ChenierLOUISIANA122024
Forked IslandLOUISIANA112024
JuniorLOUISIANA101991
Rock IslandTEXAS102024
LafitteLOUISIANA91991
Lag AtascosaTEXAS72024
Gran ChenierLOUISIANA61980

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