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

Blue-gray Gnatcatcher In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsForest birds

Blue-gray Gnatcatcher in Tamaulipan Brushlands has surged: up 195% on the route-weighted index since 1972.

+195%Since 1972TrendPercent 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 →
21Routes 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 →
36YearsYears 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 →

Blue-gray Gnatcatcher has surged in Tamaulipan Brushlands: up 195% on the route-weighted index since 1972.

Blue-gray Gnatcatcher In Tamaulipan Brushlands Population Forecast

If the recent trend holds, Blue-gray Gnatcatcher in Tamaulipan Brushlands is projected to rise about 291% by 2029 — from 0.17 in 2024 to a central estimate of 0.65 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±469.8%, with 100% of held-out values landing inside the 95% band.

+291%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 →
0.65Projected 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 →
0.00–1.595% 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 →
±469.8%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, Blue-gray Gnatcatcher in Tamaulipan Brushlands is projected to rise about 291% by 2029 — from 0.17 in 2024 to a central estimate of 0.65 (95% range 0.00–1.5). A 5-year backtest shows a typical error of ±469.8%, with 100% of held-out values landing inside the 95% band.19692029
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 →
20250.620.001.5
20260.630.001.5
20270.640.001.5
20280.650.001.5
20290.650.001.5

Routes In Tamaulipan Brushlands

Routes recording Blue-gray Gnatcatcher 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 →
CatarinaTEXAS82007
SejitaTEXAS52023
MillettTEXAS42012
Agua NuevaTEXAS32023
La PryorTEXAS32003
RandadoTEXAS22014
EncinalTEXAS22008
Catarina 2TEXAS22013
LaredoTEXAS22016
Pedro CreekTEXAS22003
Cavasara Cr.TEXAS22012
RachalTEXAS12023
KingsvilleTEXAS12004
Mirando CityTEXAS12014
George WestTEXAS12013
HondoTEXAS12024
El IndioTEXAS12007
RaymondvilleTEXAS12024
DilleyTEXAS12023
GuerraTEXAS12010
Millett 2TEXAS12022

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