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Species · Nebraska · BBS 2025 Release · 1966–2024

Violet-green Swallow Population Trend in Nebraska

All statesAerial insectivores

Violet-green Swallow in Nebraska has declined: down 39% on the route-weighted index since 1999.

-39%Since 1999TrendPercent 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 →
4Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
23YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Violet-green Swallow Trends in NebraskaNotable 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 Violet-green Swallow in Nebraska. See the full index history below.

Violet-green Swallow Population Forecast in Nebraska

If the recent trend holds, Violet-green Swallow in Nebraska is projected to fall about 66% by 2029 — from 0.19 in 2024 to a central estimate of 0.06 (95% range 0.00–0.27). A 5-year backtest shows a typical error of ±49.6%, with 100% of held-out values landing inside the 95% band.

-66%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 →
0.06Projected 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 →
0.00–0.2795% 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 →
±49.6%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, Violet-green Swallow in Nebraska is projected to fall about 66% by 2029 — from 0.19 in 2024 to a central estimate of 0.06 (95% range 0.00–0.27). A 5-year backtest shows a typical error of ±49.6%, with 100% of held-out values landing inside the 95% band.19952029
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 →
20250.070.000.28
20260.070.000.28
20270.070.000.28
20280.070.000.27
20290.060.000.27

Violet-green Swallow Survey Routes in Nebraska

Routes recording Violet-green Swallow in Nebraska.
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 →
Pine Ridge920241999
Oglala Nat. Grass.320232001
Murray Lake120172017
Crawford120161995

Violet-green Swallow Population Trend in Other States

alaskaarizonacaliforniacoloradoidahomontananevadanew-mexiconorth-dakotaoregonsouth-dakotatexasutahwashingtonwyoming

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