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Species · Virginia · BBS 2025 Release · 1966–2024

Glossy Ibis Population Trend in Virginia

All statesWetland birds

Glossy Ibis in Virginia has surged: up 20× on the route-weighted index since 1979.

20×Since 1979TrendPercent 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 →
29YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Glossy Ibis Trends in VirginiaNotable 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 →

Glossy Ibis has surged in Virginia: up 20× on the route-weighted index since 1979.

Glossy Ibis Population Forecast in Virginia

If the recent trend holds, Glossy Ibis in Virginia is projected to stay roughly flat through 2029, near 1.1 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±1618%, with 80% of held-out values landing inside the 95% band.

n/aChange 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 →
1.1Projected 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 →
0.00–3.595% 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 →
±1618%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, Glossy Ibis in Virginia is projected to stay roughly flat through 2029, near 1.1 (95% range 0.00–3.5). A 5-year backtest shows a typical error of ±1618%, with 80% 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 →
20251.10.003.4
20261.10.003.4
20271.10.003.4
20281.10.003.5
20291.10.003.5

Glossy Ibis Survey Routes in Virginia

Routes recording Glossy Ibis in Virginia.
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 →
Cornland219951995
Quinby119791969
Chincoteag W120241992
Cape Charles120171992

Glossy Ibis Population Trend in Other States

alabamaconnecticutdelawarefloridageorgialouisianamainemarylandmassachusettsnew-hampshirenew-jerseynew-yorknorth-carolinarhode-islandsouth-carolinasouth-dakotatexas

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