BirdAnalyst
Species · New Mexico · BBS 2025 Release · 1966–2024

Black-tailed Gnatcatcher Population Trend in New Mexico

All statesArid-land birds

Black-tailed Gnatcatcher in New Mexico has surged: up 215% on the route-weighted index since 1995.

+215%Since 1995TrendPercent 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 →
9Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
31YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-tailed Gnatcatcher Trends in New MexicoNotable 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 →

Black-tailed Gnatcatcher has surged in New Mexico: up 215% on the route-weighted index since 1995.

Black-tailed Gnatcatcher Population Forecast in New Mexico

If the recent trend holds, Black-tailed Gnatcatcher in New Mexico is projected to stay roughly flat through 2029, near 0.20 (95% range 0.02–0.38). A 5-year backtest shows a typical error of ±18.9%, with 100% of held-out values landing inside the 95% band.

+4%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 →
0.20Projected 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 →
0.02–0.3895% 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 →
±18.9%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, Black-tailed Gnatcatcher in New Mexico is projected to stay roughly flat through 2029, near 0.20 (95% range 0.02–0.38). A 5-year backtest shows a typical error of ±18.9%, with 100% of held-out values landing inside the 95% band.19812029
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 →
20250.190.010.37
20260.190.010.37
20270.200.020.38
20280.200.020.38
20290.200.020.38

Black-tailed Gnatcatcher Survey Routes in New Mexico

Routes recording Black-tailed Gnatcatcher in New Mexico.
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 →
Red Rock320241998
Hatchet Peak320242004
Mesilla220001995
Columbus220242018
San Simon120162009
Gage120242003
Jornada120231981
Sunshine Wll120191996
Rodeo120222009

Black-tailed Gnatcatcher Population Trend in Other States

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