BirdAnalyst
Species · BCR 35 · BBS 2025 Release · 1966–2024

Harris's Hawk In Chihuahuan Desert

All regionsChihuahuan DesertGeneralists

Harris's Hawk in Chihuahuan Desert has collapsed: down 88% on the route-weighted index since 1976.

-88%Since 1976TrendPercent 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 →
17Routes 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 →
34YearsYears 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 →

Harris's Hawk has collapsed in Chihuahuan Desert: down 88% on the route-weighted index since 1976.

Forecast

If the recent trend holds, Harris's Hawk in Chihuahuan Desert is projected to stay roughly flat through 2023, near 0.02 (95% range 0.00–0.26). A 5-year backtest shows a typical error of ±159.5%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2023TrendPercent 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 →
0.02Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2695% 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 →
±159.5%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, Harris's Hawk in Chihuahuan Desert is projected to stay roughly flat through 2023, near 0.02 (95% range 0.00–0.26). A 5-year backtest shows a typical error of ±159.5%, with 100% of held-out values landing inside the 95% band.19712023
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 →
20190.050.000.28
20200.040.000.28
20210.040.000.27
20220.030.000.27
20230.020.000.26

Routes In Chihuahuan Desert

Routes recording Harris's Hawk in Chihuahuan Desert.
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 →
LangtryTEXAS31995
Bitter LakeNEW-MEXICO22007
LongfellowTEXAS22002
AltudaTEXAS21998
GirvinTEXAS22009
Ft. StocktonTEXAS22009
Quitman Cyn.TEXAS22001
PumpvilleTEXAS22012
GageNEW-MEXICO12007
JornadaNEW-MEXICO12012
RodeoNEW-MEXICO12000
Sunshine WllNEW-MEXICO12014
ComstockTEXAS12002
OzonaTEXAS12001
PresidioTEXAS12015
Coyanda DrawTEXAS12008
Quitman Canyon 2TEXAS12018

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