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

Cave Swallow In Chihuahuan Desert

All regionsChihuahuan DesertAerial insectivores

Cave Swallow in Chihuahuan Desert has risen sharply: up 70% on the route-weighted index since 1984.

+70%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 →
20Routes 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 →
36YearsYears 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 →

Cave Swallow has risen sharply in Chihuahuan Desert: up 70% on the route-weighted index since 1984.

Cave Swallow In Chihuahuan Desert Population Forecast

If the recent trend holds, Cave Swallow in Chihuahuan Desert is projected to rise about 30× by 2029 — from 0.10 in 2024 to a central estimate of 3.1 (95% range 0.09–6.2). A 5-year backtest shows a typical error of ±1316.1%, with 20% of held-out values landing inside the 95% band.

30×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 →
3.1Projected 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 →
0.09–6.295% 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 →
±1316.1%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, Cave Swallow in Chihuahuan Desert is projected to rise about 30× by 2029 — from 0.10 in 2024 to a central estimate of 3.1 (95% range 0.09–6.2). A 5-year backtest shows a typical error of ±1316.1%, with 20% of held-out values landing inside the 95% band.19802029
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 →
20252.90.006.0
20263.00.006.0
20273.00.006.1
20283.10.046.1
20293.10.096.2

Routes In Chihuahuan Desert

Routes recording Cave Swallow 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 →
Delaware CrkTEXAS172009
GirvinTEXAS112017
Ft. StocktonTEXAS82023
Quitman Cyn.TEXAS81999
PresidioTEXAS42021
OzonaTEXAS32022
Ft. DavisTEXAS32012
Quitman Canyon 2TEXAS32019
MesillaNEW-MEXICO22000
ComstockTEXAS22019
AltudaTEXAS22023
Coyanda DrawTEXAS21994
ToyahvaleTEXAS22024
Sierra BlancTEXAS22019
MarfaTEXAS22017
PinonNEW-MEXICO12011
LongfellowTEXAS12024
Casa PiedraTEXAS12012
Devils R CynTEXAS12016
MarathonTEXAS12023

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