BirdAnalyst
Species · BCR 13 · BBS 2025 Release · 1966–2024

Common Gallinule In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainWetland birds

Common Gallinule in Lower Great Lakes / St. Lawrence Plain has fallen sharply: down 58% on the route-weighted index since 1970.

-58%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 →
21Routes 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 →
35YearsYears 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 →

No notable trend signals for Common Gallinule in Lower Great Lakes / St. Lawrence Plain. See the full index history below.

Common Gallinule In Lower Great Lakes / St. Lawrence Plain Population Forecast

If the recent trend holds, Common Gallinule in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±13.2%, with 100% 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 →
0.01Projected 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 →
0.00–0.0495% 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 →
±13.2%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, Common Gallinule in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2029, near 0.01 (95% range 0.00–0.04). A 5-year backtest shows a typical error of ±13.2%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.010.000.05
20260.010.000.05
20270.010.000.04
20280.010.000.04
20290.010.000.04

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Common Gallinule in Lower Great Lakes / St. Lawrence Plain.
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 →
Alder CreekNEW-YORK41969
GarrettsvileOHIO21972
Herner CrnsOHIO21988
Grand IsleVERMONT21974
DuanesburgNEW-YORK12009
OrleansNEW-YORK12010
Mt MorrisNEW-YORK11974
West SenecaNEW-YORK11979
CastileNEW-YORK12011
ByronNEW-YORK11988
Cicero CtrNEW-YORK11971
WatertownNEW-YORK12005
SalemNEW-YORK11977
WaddingtonNEW-YORK11998
OgdensburgNEW-YORK12024
NaplesNEW-YORK11972
PhiladelphiaNEW-YORK12008
Slippery RkPENNSYLVANIA11985
Ferris CrnrsPENNSYLVANIA12017
TeeplevillePENNSYLVANIA11973
HinesburgVERMONT11982

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