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

Verdin In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsArid-land birds

Verdin in Tamaulipan Brushlands has collapsed: down 81% on the route-weighted index since 1969.

-81%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 →
25Routes 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 →
56YearsYears 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 declinecomputed 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 →

Verdin has collapsed in Tamaulipan Brushlands: down 81% on the route-weighted index since 1969.

Verdin In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Verdin in Tamaulipan Brushlands is projected to fall about 52% by 2029 — from 4.8 in 2024 to a central estimate of 2.3 (95% range 0.00–8.9). A 5-year backtest shows a typical error of ±112.4%, with 100% of held-out values landing inside the 95% band.

-52%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 →
2.3Projected 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 →
0.00–8.995% 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 →
±112.4%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, Verdin in Tamaulipan Brushlands is projected to fall about 52% by 2029 — from 4.8 in 2024 to a central estimate of 2.3 (95% range 0.00–8.9). A 5-year backtest shows a typical error of ±112.4%, 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 →
20252.50.009.0
20262.40.009.0
20272.40.008.9
20282.30.008.9
20292.30.008.9

Routes In Tamaulipan Brushlands

Routes recording Verdin 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 →
GuerraTEXAS312018
Millett 2TEXAS242024
El SauzTEXAS102015
Catarina 2TEXAS102017
Agua NuevaTEXAS92023
HondoTEXAS82024
San YgnacioTEXAS71982
Encinal 2TEXAS62024
Catarina 3TEXAS62024
George WestTEXAS52024
RaymondvilleTEXAS52024
MillettTEXAS42012
ZapataTEXAS31979
LaredoTEXAS32021
KingsvilleTEXAS22002
EncinalTEXAS22010
CatarinaTEXAS22010
El IndioTEXAS22007
SejitaTEXAS22024
Cavasara Cr.TEXAS22013
RachalTEXAS12023
RandadoTEXAS12018
Mirando CityTEXAS12018
La PryorTEXAS12005
DilleyTEXAS12024

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