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Species · Maryland · BBS 2026 Release · 1966–2025

Glossy Ibis Population Trend in Maryland

All statesWetland birds

Glossy Ibis in Maryland has surged: up 702% on the route-weighted index since 1968.

+702%Since 1968TrendPercent 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 →
13Routes 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 →
54YearsYears 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 MarylandNotable 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 Maryland: up 701% on the route-weighted index since 1968.

Glossy Ibis Population Forecast in Maryland

If the recent trend holds, Glossy Ibis in Maryland is projected to rise about 197% by 2030 — from 0.24 in 2025 to a central estimate of 0.70 (95% range 0.00–2.1). A 5-year backtest shows a typical error of ±113.2%, with 100% of held-out values landing inside the 95% band.

+197%Change by 2030TrendPercent 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 →
0.70Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–2.195% 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 →
±113.2%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 Maryland is projected to rise about 197% by 2030 — from 0.24 in 2025 to a central estimate of 0.70 (95% range 0.00–2.1). A 5-year backtest shows a typical error of ±113.2%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.680.002.0
20270.690.002.0
20280.690.002.0
20290.700.002.1
20300.700.002.1

Glossy Ibis Survey Routes in Maryland

Routes recording Glossy Ibis in Maryland.
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 →
Golden Hill2519721972
Pomfret1519941994
Berlin1120211980
Newark820251966
Furnace Town720182018
Honga620241972
Sinepuxent419751966
Indiantown320041989
Snow Hill219761970
Elkton120161971
Grove Neck119951995
Madison120251974
Cokesbury120211983

Glossy Ibis Population Trend in Other States

alabamaconnecticutdelawarefloridageorgialouisianamainemassachusettsnew-hampshirenew-jerseynew-yorknorth-carolinarhode-islandsouth-carolinasouth-dakotatexasvirginia

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.