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Species · Connecticut · BBS 2025 Release · 1966–2024

Great Black-backed Gull Population Trend in Connecticut

All statesWetland birds

Great Black-backed Gull in Connecticut has held roughly steady: up 7% on the route-weighted index since 1976.

+7%Since 1976
3Routes In State
25Years

Notable Great Black-backed Gull Trends in Connecticut

No notable trend signals for Great Black-backed Gull in Connecticut. See the full index history below.

Great Black-backed Gull Population Forecast in Connecticut

If the recent trend holds, Great Black-backed Gull in Connecticut is projected to rise about 20% by 2028 — from 0.18 in 2023 to a central estimate of 0.22 (95% range 0.00–0.49). A 5-year backtest shows a typical error of ±237%, with 80% of held-out values landing inside the 95% band.

+20%Change by 2028
0.22Projected 2028 index
0.00–0.4995% range
±237%Backtest error
19732028
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20240.210.000.49
20250.210.000.49
20260.220.000.49
20270.220.000.49
20280.220.000.49

Great Black-backed Gull Survey Routes in Connecticut

Routes recording Great Black-backed Gull in Connecticut.
Mystic220231973
Westbrook119941986
Mid Haddam120052005

Great Black-backed Gull Population Trend in Other States

delawaremainemarylandmassachusettsnew-hampshirenew-jerseynew-yorknorth-carolinaohiorhode-islandvermontvirginia

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