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

Lark Sparrow In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsGrassland birds

Lark Sparrow in Tamaulipan Brushlands has edged down: down 22% on the route-weighted index since 1969.

-22%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 →
28Routes 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 →

No notable trend signals for Lark Sparrow in Tamaulipan Brushlands. See the full index history below.

Lark Sparrow In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Lark Sparrow in Tamaulipan Brushlands is projected to fall about 26% by 2029 — from 10 in 2024 to a central estimate of 7.6 (95% range 0.00–15). A 5-year backtest shows a typical error of ±19.1%, with 100% of held-out values landing inside the 95% band.

-26%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 →
0.00–1595% 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 →
±19.1%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, Lark Sparrow in Tamaulipan Brushlands is projected to fall about 26% by 2029 — from 10 in 2024 to a central estimate of 7.6 (95% range 0.00–15). A 5-year backtest shows a typical error of ±19.1%, 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 →
20257.90.2816
20267.90.2016
20277.80.1215
20287.70.0415
20297.60.0015

Routes In Tamaulipan Brushlands

Routes recording Lark 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 →
Pedro CreekTEXAS432005
RaymondvilleTEXAS292024
HondoTEXAS282024
RachalTEXAS212023
Catarina 3TEXAS152024
Cavasara Cr.TEXAS132023
George WestTEXAS122024
El SauzTEXAS122023
ProgresoTEXAS122011
La PryorTEXAS112017
HeidelbergTEXAS112024
Agua NuevaTEXAS92023
EncinalTEXAS92010
ZapataTEXAS71987
Catarina 2TEXAS72017
Millett 2TEXAS72024
DilleyTEXAS62024
Encinal 2TEXAS52024
MillettTEXAS52012
KingsvilleTEXAS42024
GuerraTEXAS42023
LaredoTEXAS42018
Mirando CityTEXAS32024
SejitaTEXAS32024
CatarinaTEXAS22010

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