BirdAnalyst
Species · BCR 37 · BBS 2025 Release · 1966–2024

Olive Sparrow In Gulf Coastal Prairie

All regionsGulf Coastal PrairieGeneralists

Olive Sparrow in Gulf Coastal Prairie has surged: up 11× on the route-weighted index since 1971.

11×Since 1971TrendPercent 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 →
8Routes 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 →
51YearsYears 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 →

Olive Sparrow has surged in Gulf Coastal Prairie: up 11× on the route-weighted index since 1971.

Olive Sparrow In Gulf Coastal Prairie Population Forecast

If the recent trend holds, Olive Sparrow in Gulf Coastal Prairie is projected to rise about 88% by 2029 — from 1.7 in 2024 to a central estimate of 3.2 (95% range 1.3–5.1). A 5-year backtest shows a typical error of ±62.3%, with 100% of held-out values landing inside the 95% band.

+88%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 →
3.2Projected 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 →
1.3–5.195% 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 →
±62.3%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, Olive Sparrow in Gulf Coastal Prairie is projected to rise about 88% by 2029 — from 1.7 in 2024 to a central estimate of 3.2 (95% range 1.3–5.1). A 5-year backtest shows a typical error of ±62.3%, 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 →
20253.01.14.9
20263.11.25.0
20273.11.25.0
20283.21.35.1
20293.21.35.1

Routes In Gulf Coastal Prairie

Routes recording Olive Sparrow in Gulf Coastal Prairie.
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 →
Lag AtascosaTEXAS262024
Loyola BeachTEXAS212009
San PedroTEXAS182023
Loyola Beach 2TEXAS92024
L. Atascosa NwrTEXAS62023
Bayside 2TEXAS21998
PetronilaTEXAS12024
Bayside 3TEXAS12023

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