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

Bullock's Oriole In Tamaulipan Brushlands

All regionsTamaulipan BrushlandsGeneralists

Bullock's Oriole in Tamaulipan Brushlands has risen sharply: up 64% on the route-weighted index since 1969.

+64%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 →
26Routes 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 →

Bullock's Oriole has risen sharply in Tamaulipan Brushlands: up 64% on the route-weighted index since 1969.

Forecast

If the recent trend holds, Bullock's Oriole in Tamaulipan Brushlands is projected to fall about 24% by 2029 — from 7.4 in 2024 to a central estimate of 5.6 (95% range 2.4–8.9). A 5-year backtest shows a typical error of ±37.8%, with 60% of held-out values landing inside the 95% band.

-24%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 →
5.6Projected 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 →
2.4–8.995% 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 →
±37.8%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, Bullock's Oriole in Tamaulipan Brushlands is projected to fall about 24% by 2029 — from 7.4 in 2024 to a central estimate of 5.6 (95% range 2.4–8.9). A 5-year backtest shows a typical error of ±37.8%, with 60% 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 →
20255.42.28.7
20265.52.28.7
20275.52.38.8
20285.62.38.8
20295.62.48.9

Routes In Tamaulipan Brushlands

Routes recording Bullock's Oriole 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 →
RachalTEXAS172023
Agua NuevaTEXAS152023
DilleyTEXAS152024
GuerraTEXAS152023
Millett 2TEXAS152024
George WestTEXAS132024
Catarina 3TEXAS112024
EncinalTEXAS92010
HondoTEXAS92024
KingsvilleTEXAS82024
El SauzTEXAS82023
SejitaTEXAS82024
CatarinaTEXAS52010
Encinal 2TEXAS52024
LaredoTEXAS52023
ZapataTEXAS41984
Catarina 2TEXAS42017
MillettTEXAS42012
RaymondvilleTEXAS32024
RandadoTEXAS22023
Mirando CityTEXAS22024
San YgnacioTEXAS21985
La PryorTEXAS12010
El IndioTEXAS12007
Pedro CreekTEXAS12010

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