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

Purple Martin In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsAerial insectivores

Purple Martin in Tamaulipan Brushlands has surged: up 142% on the route-weighted index since 1969.

+142%Since 1969TrendPercent 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 →
57YearsYears 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 →

Purple Martin has surged in Tamaulipan Brushlands: up 142% on the route-weighted index since 1969.

Purple Martin In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Purple Martin in Tamaulipan Brushlands is projected to fall about 31% by 2029 — from 11 in 2024 to a central estimate of 7.6 (95% range 0.00–18). A 5-year backtest shows a typical error of ±49.8%, with 100% of held-out values landing inside the 95% band.

-31%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 →
7.6Projected 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 →
0.00–1895% 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 →
±49.8%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, Purple Martin in Tamaulipan Brushlands is projected to fall about 31% by 2029 — from 11 in 2024 to a central estimate of 7.6 (95% range 0.00–18). A 5-year backtest shows a typical error of ±49.8%, 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 →
20257.90.0019
20267.80.0019
20277.70.0019
20287.70.0019
20297.60.0018

Routes In Tamaulipan Brushlands

Routes recording Purple Martin 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 →
George WestTEXAS802024
Millett 2TEXAS192024
HondoTEXAS172024
RachalTEXAS142023
Mirando CityTEXAS132022
ProgresoTEXAS132007
ZapataTEXAS121984
KingsvilleTEXAS102024
La PryorTEXAS72004
Agua NuevaTEXAS52023
El IndioTEXAS41994
RaymondvilleTEXAS42019
MillettTEXAS42010
CatarinaTEXAS32008
DilleyTEXAS32018
Encinal 2TEXAS32024
RandadoTEXAS22023
Catarina 2TEXAS22013
Catarina 3TEXAS22024
SejitaTEXAS22023
Cavasara Cr.TEXAS22013
EncinalTEXAS12010
El SauzTEXAS12005
HeidelbergTEXAS12024

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