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

Black-throated Sparrow In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsArid-land birds

Black-throated Sparrow in Tamaulipan Brushlands has collapsed: down 94% on the route-weighted index since 1969.

-94%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 →
58YearsYears 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 →

Black-throated Sparrow has collapsed in Tamaulipan Brushlands: down 94% on the route-weighted index since 1969.

Black-throated Sparrow In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Black-throated Sparrow in Tamaulipan Brushlands is projected to fall about 100% by 2030 — from 5.2 in 2025 to a central estimate of 0.00 (95% range 0.00–28). A 5-year backtest shows a typical error of ±154.6%, with 100% of held-out values landing inside the 95% band.

-100%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 →
0.00Projected 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 →
0.00–2895% 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 →
±154.6%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, Black-throated Sparrow in Tamaulipan Brushlands is projected to fall about 100% by 2030 — from 5.2 in 2025 to a central estimate of 0.00 (95% range 0.00–28). A 5-year backtest shows a typical error of ±154.6%, 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 →
20260.000.0028
20270.000.0028
20280.000.0028
20290.000.0028
20300.000.0028

Routes In Tamaulipan Brushlands

Routes recording Black-throated Sparrow 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 →
EncinalTEXAS432010
CatarinaTEXAS422010
Catarina 2TEXAS402017
El IndioTEXAS322007
LaredoTEXAS252023
Catarina 3TEXAS182025
San YgnacioTEXAS131985
Cavasara Cr.TEXAS132025
Encinal 2TEXAS102025
Mirando CityTEXAS62025
ZapataTEXAS51987
Agua NuevaTEXAS42023
DilleyTEXAS42025
Millett 2TEXAS42024
RachalTEXAS32023
El SauzTEXAS32023
GuerraTEXAS32025
SejitaTEXAS32021
George WestTEXAS22025
La PryorTEXAS22003
MillettTEXAS22012
Pedro CreekTEXAS22010
KingsvilleTEXAS11985
RandadoTEXAS12024
HondoTEXAS12025

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