BirdAnalyst
Species · BCR 35 · BBS 2026 Release · 1966–2025

Hepatic Tanager In Chihuahuan Desert

All regionsChihuahuan DesertForest birds

Hepatic Tanager in Chihuahuan Desert has collapsed: down 83% on the route-weighted index since 1974.

-83%Since 1974TrendPercent 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 →
10Routes 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 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 →

Hepatic Tanager has collapsed in Chihuahuan Desert: down 83% on the route-weighted index since 1974.

Hepatic Tanager In Chihuahuan Desert Population Forecast

If the recent trend holds, Hepatic Tanager in Chihuahuan Desert is projected to stay roughly flat through 2030, near 0.29 (95% range 0.00–0.66). A 5-year backtest shows a typical error of ±831.6%, with 20% of held-out values landing inside the 95% band.

n/aChange 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 →
0.29Projected 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 →
0.00–0.6695% 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 →
±831.6%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, Hepatic Tanager in Chihuahuan Desert is projected to stay roughly flat through 2030, near 0.29 (95% range 0.00–0.66). A 5-year backtest shows a typical error of ±831.6%, with 20% of held-out values landing inside the 95% band.19702030
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 →
20260.290.000.66
20270.290.000.66
20280.290.000.66
20290.290.000.66
20300.290.000.66

Routes In Chihuahuan Desert

Routes recording Hepatic Tanager 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 →
Capitan Mtn.NEW-MEXICO32017
Bear MtnTEXAS32012
CloudcroftNEW-MEXICO22017
CarrizozoNEW-MEXICO12024
PinonNEW-MEXICO12024
QueenNEW-MEXICO12021
ValentineTEXAS11987
ToyahvaleTEXAS12013
Salt FlatTEXAS12014
Chisos BasinTEXAS12025

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