BirdAnalyst
Species · BCR 37 · BBS 2026 Release · 1966–2025

Swainson's Hawk In Gulf Coastal Prairie

All regionsGulf Coastal PrairieBirds of prey

Swainson's Hawk in Gulf Coastal Prairie has risen sharply: up 61% on the route-weighted index since 1984.

+61%Since 1984TrendPercent 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 →
28Routes 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 →
35YearsYears 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 →

Swainson's Hawk has risen sharply in Gulf Coastal Prairie: up 61% on the route-weighted index since 1984.

Swainson's Hawk In Gulf Coastal Prairie Population Forecast

If the recent trend holds, Swainson's Hawk in Gulf Coastal Prairie is projected to stay roughly flat through 2030, near 0.35 (95% range 0.00–0.73). A 5-year backtest shows a typical error of ±160.8%, with 80% of held-out values landing inside the 95% band.

-4%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 →
0.35Projected 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 →
0.00–0.7395% 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 →
±160.8%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, Swainson's Hawk in Gulf Coastal Prairie is projected to stay roughly flat through 2030, near 0.35 (95% range 0.00–0.73). A 5-year backtest shows a typical error of ±160.8%, with 80% of held-out values landing inside the 95% band.19682030
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 →
20260.330.000.71
20270.340.000.71
20280.340.000.72
20290.350.000.72
20300.350.000.73

Routes In Gulf Coastal Prairie

Routes recording Swainson's Hawk 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 →
McfaddinTEXAS152009
Lag AtascosaTEXAS32025
RichardLOUISIANA22016
Ville PlatteLOUISIANA22011
ChinquapinTEXAS22025
HackberryLOUISIANA12014
GlencoeLOUISIANA12014
EstherLOUISIANA12010
MauriceLOUISIANA12007
KaplanLOUISIANA12009
Ltl ChenierLOUISIANA12018
Hackberry 2LOUISIANA12021
WoodlawnLOUISIANA12019
Forked IslandLOUISIANA12025
Vinton 2LOUISIANA12014
PetronilaTEXAS12021
Hinkles FerTEXAS12019
IndianolaTEXAS11999
WinnieTEXAS12023
StowellTEXAS12023
DanburyTEXAS12025
KatyTEXAS12023
Rock IslandTEXAS12022
Oyster LakeTEXAS12025
Port AcresTEXAS12023

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