BirdAnalyst
Species · BCR 36 · BBS 2026 Release · 1966–2025

Northern Rough-winged Swallow In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsAerial insectivores

Northern Rough-winged Swallow in Tamaulipan Brushlands has declined: down 48% on the route-weighted index since 1970.

-48%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 →
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 →
41YearsYears 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 Northern Rough-winged Swallow in Tamaulipan Brushlands. See the full index history below.

Northern Rough-winged Swallow In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Northern Rough-winged Swallow in Tamaulipan Brushlands is projected to rise about 155% by 2030 — from 0.46 in 2025 to a central estimate of 1.2 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±996.5%, with 100% of held-out values landing inside the 95% band.

+155%Change 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 →
1.2Projected 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 →
0.00–7.095% 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 →
±996.5%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, Northern Rough-winged Swallow in Tamaulipan Brushlands is projected to rise about 155% by 2030 — from 0.46 in 2025 to a central estimate of 1.2 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±996.5%, with 100% of held-out values landing inside the 95% band.19672030
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 →
20261.20.007.1
20271.20.007.1
20281.20.007.1
20291.20.007.1
20301.20.007.0

Routes In Tamaulipan Brushlands

Routes recording Northern Rough-winged Swallow 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 →
ZapataTEXAS311987
Pedro CreekTEXAS72005
George WestTEXAS61974
CatarinaTEXAS61975
RachalTEXAS52025
El IndioTEXAS42000
SejitaTEXAS42015
LaredoTEXAS42018
La PryorTEXAS32010
Agua NuevaTEXAS22014
KingsvilleTEXAS22024
Mirando CityTEXAS22014
HondoTEXAS22003
GuerraTEXAS22010
ProgresoTEXAS22008
RandadoTEXAS12013
RaymondvilleTEXAS11994
Encinal 2TEXAS12023
MillettTEXAS11998
HeidelbergTEXAS12023

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