BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Blue-throated Mountain-gem

TrochilidaeForest birdsLampornis clemenciae

Blue-throated Mountain-gem has edged down: down 21% on the route-weighted index since 1979.

-21%Since 1979TrendPercent 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 →
6RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
30Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Blue-throated Mountain-gem

The Blue-throated Mountain-gem (Lampornis clemenciae) is a North American member of the Hummingbirds (Trochilidae). In this analysis it is grouped with the forest birds.

Size
3–5 in long (8–13 cm) — a tiny hovering bird (typical for the family)
Habitat
Woodlands and forest edges, including wooded suburbs and parks.
Diet
Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
Range
Recorded on 6 Breeding Bird Survey routes across 2 states, most concentrated in the Sierra Madre Occidental.
Family
Trochilidae · Forest birds

Notable Blue-throated Mountain-gem TrendsNotable 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 Blue-throated Mountain-gem. See the full index history below.

Blue-throated Mountain-gem Population Forecast

If the recent trend holds, Blue-throated Mountain-gem is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.00). A 5-year backtest shows a typical error of ±68.4%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.00Projected 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 →
0.00–0.0095% 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 →
±68.4%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, Blue-throated Mountain-gem is projected to stay roughly flat through 2029, near 0.00 (95% range 0.00–0.00). A 5-year backtest shows a typical error of ±68.4%, with 100% of held-out values landing inside the 95% band.19772029
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 →
20250.000.000.00
20260.000.000.00
20270.000.000.00
20280.000.000.00
20290.000.000.00

Where the Blue-throated Mountain-gem Is Detected

BBS routes recording Blue-throated Mountain-gem, sized by most recent count.

Blue-throated Mountain-gem Population Trend by State

Blue-throated Mountain-gem population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Arizona-50%19795
Texasinsufficient datan/a1

Blue-throated Mountain-gem Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Blue-throated Mountain-gem population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Sierra Madre Occidental-53%19795

Blue-throated Mountain-gem Conservation Status

Our route-weighted index shows it down about 21% since 1979.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.