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

Herring Gull In Lower Great Lakes / St. Lawrence Plain

All regionsLower Great Lakes / St. Lawrence PlainWetland birds

Herring Gull in Lower Great Lakes / St. Lawrence Plain has edged up: up 18% on the route-weighted index since 1969.

+18%Since 1969TrendPercent 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 →
27Routes 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 →
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 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 Herring Gull in Lower Great Lakes / St. Lawrence Plain. See the full index history below.

Forecast

If the recent trend holds, Herring Gull in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2029, near 0.09 (95% range 0.00–0.67). A 5-year backtest shows a typical error of ±128.9%, 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 →
0.09Projected 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 →
0.00–0.6795% 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 →
±128.9%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, Herring Gull in Lower Great Lakes / St. Lawrence Plain is projected to stay roughly flat through 2029, near 0.09 (95% range 0.00–0.67). A 5-year backtest shows a typical error of ±128.9%, with 80% 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 →
20250.100.000.68
20260.100.000.68
20270.100.000.67
20280.090.000.67
20290.090.000.67

Routes In Lower Great Lakes / St. Lawrence Plain

Routes recording Herring Gull 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 →
St JohnsburgNEW-YORK441986
CrescentNEW-YORK51998
HiramOHIO41993
HamburgNEW-YORK31997
E YoungstownNEW-YORK32013
HighlandNEW-YORK22022
PenfieldNEW-YORK21995
WatertownNEW-YORK21969
ClintonNEW-YORK22006
GarrettsvileOHIO21991
LenoxOHIO22015
RhinebeckNEW-YORK11984
W ShokanNEW-YORK12000
Ballston LkNEW-YORK11978
MacdougallNEW-YORK11999
Cicero CtrNEW-YORK12009
WaddingtonNEW-YORK11987
ParishvilleNEW-YORK11985
HopkintonNEW-YORK11969
WillsboroNEW-YORK12010
NaplesNEW-YORK12022
PittsfieldOHIO12008
PeruOHIO11975
Herner CrnsOHIO12024
HinesburgVERMONT11988

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