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Species · North Carolina · BBS 2025 Release · 1966–2024

Glossy Ibis Population Trend in North Carolina

All statesWetland birds

Glossy Ibis in North Carolina has collapsed: down 90% on the route-weighted index since 1970.

-90%Since 1970TrendPercent 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 →
6Routes 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 →
33YearsYears 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 North CarolinaNotable 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 declinecomputed 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 collapsed in North Carolina: down 90% on the route-weighted index since 1970.

Glossy Ibis Population Forecast in North Carolina

If the recent trend holds, Glossy Ibis in North Carolina is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±193.8%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2028TrendPercent 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 →
0.00Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.4295% 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 →
±193.8%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, Glossy Ibis in North Carolina is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.42). A 5-year backtest shows a typical error of ±193.8%, with 100% of held-out values landing inside the 95% band.19672028
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 →
20240.010.000.42
20250.000.000.42
20260.000.000.42
20270.000.000.42
20280.000.000.42

Glossy Ibis Survey Routes in North Carolina

Routes recording Glossy Ibis in North Carolina.
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 →
Wards Corner619861986
Myrtle Grove319931967
Cayton320162016
Jarvisburg 2220152015
Shallotte119881971
Merrimon120231968

Glossy Ibis Population Trend in Other States

alabamaconnecticutdelawarefloridageorgialouisianamainemarylandmassachusettsnew-hampshirenew-jerseynew-yorkrhode-islandsouth-carolinasouth-dakotatexasvirginia

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