BirdAnalyst
Species · BCR 36 · BBS 2025 Release · 1966–2024

Chimney Swift In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsAerial insectivores

Chimney Swift in Tamaulipan Brushlands has declined: down 40% on the route-weighted index since 1970.

-40%Since 1970TrendPercent 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 →
24Routes 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 →
55YearsYears 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 →

No notable trend signals for Chimney Swift in Tamaulipan Brushlands. See the full index history below.

Chimney Swift In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Chimney Swift in Tamaulipan Brushlands is projected to fall about 22% by 2029 — from 0.83 in 2024 to a central estimate of 0.65 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±35%, with 100% of held-out values landing inside the 95% band.

-22%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 →
0.65Projected 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 →
0.00–3.595% 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 →
±35%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, Chimney Swift in Tamaulipan Brushlands is projected to fall about 22% by 2029 — from 0.83 in 2024 to a central estimate of 0.65 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±35%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.820.003.7
20260.780.003.6
20270.730.003.6
20280.690.003.6
20290.650.003.5

Routes In Tamaulipan Brushlands

Routes recording Chimney Swift in Tamaulipan Brushlands.
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 →
EncinalTEXAS42004
CatarinaTEXAS41999
HeidelbergTEXAS42023
ZapataTEXAS31974
RandadoTEXAS32024
George WestTEXAS32024
Pedro CreekTEXAS32005
KingsvilleTEXAS22023
GuerraTEXAS22018
Encinal 2TEXAS22022
SejitaTEXAS22018
MillettTEXAS22009
RachalTEXAS12013
Mirando CityTEXAS12024
San YgnacioTEXAS11967
La PryorTEXAS12003
HondoTEXAS12024
RaymondvilleTEXAS12024
El SauzTEXAS12023
DilleyTEXAS12022
ProgresoTEXAS12011
LaredoTEXAS12017
Millett 2TEXAS12024
Cavasara Cr.TEXAS11998

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