Ring-billed Gull
Ring-billed Gull has surged: up 155% on the route-weighted index since 1968.
About the Ring-billed Gull
The Ring-billed Gull (Larus delawarensis) is a North American member of the Gulls, Terns & Skimmers (Laridae). In this analysis it is grouped with the wetland birds.
- Size
- 8.5–31.5 in long (22–80 cm) — a long-winged waterbird (typical for the family)
- Habitat
- Marshes, ponds, lakeshores and other freshwater wetlands.
- Diet
- Aquatic invertebrates, small fish, frogs and plant matter.
- Range
- Recorded on 884 Breeding Bird Survey routes across 45 states, most concentrated in the Great Basin.
- Family
- Laridae · Wetland birds
Notable Ring-billed Gull Trends
Ring-billed Gull has surged in surveyed states: up 155% on the route-weighted index since 1968.
Ring-billed Gull Population Forecast
If the recent trend holds, Ring-billed Gull is projected to rise about 88% by 2029 — from 1.3 in 2024 to a central estimate of 2.5 (95% range 0.65–4.3). A 5-year backtest shows a typical error of ±154.2%, with 40% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 2.4 | 0.59 | 4.3 |
| 2026 | 2.5 | 0.60 | 4.3 |
| 2027 | 2.5 | 0.62 | 4.3 |
| 2028 | 2.5 | 0.63 | 4.3 |
| 2029 | 2.5 | 0.65 | 4.3 |
Where the Ring-billed Gull Is Detected
BBS routes recording Ring-billed Gull, sized by most recent count.
Ring-billed Gull Population Trend by State
| Alabama | -40% | 1974 | 8 |
| Arizona | insufficient data | n/a | 1 |
| California | +8% | 1973 | 46 |
| Colorado | +59% | 1989 | 32 |
| Connecticut | -19% | 1982 | 8 |
| Delaware | -66% | 1968 | 12 |
| Florida | -9% | 1971 | 20 |
| Georgia | insufficient data | n/a | 2 |
| Idaho | -76% | 1971 | 31 |
| Illinois | +283% | 1979 | 15 |
| Indiana | +310% | 1983 | 13 |
| Iowa | insufficient data | n/a | 5 |
| Kansas | -95% | 1970 | 3 |
| Kentucky | insufficient data | n/a | 1 |
| Louisiana | insufficient data | n/a | 7 |
| Maine | +73% | 1987 | 22 |
| Maryland | 11× | 1968 | 28 |
| Massachusetts | -85% | 1972 | 10 |
| Michigan | 47× | 1969 | 76 |
| Minnesota | +507% | 1970 | 51 |
| Missouri | insufficient data | n/a | 1 |
| Montana | 11× | 1970 | 49 |
| Nebraska | insufficient data | n/a | 7 |
| Nevada | -25% | 1995 | 7 |
| New Hampshire | -54% | 1991 | 5 |
| New Jersey | +78% | 1977 | 14 |
| New Mexico | insufficient data | n/a | 1 |
| New York | 52× | 1968 | 65 |
| North Carolina | -79% | 1969 | 13 |
| North Dakota | +855% | 1969 | 42 |
| Ohio | -44% | 1969 | 25 |
| Oklahoma | insufficient data | n/a | 1 |
| Oregon | -45% | 1972 | 41 |
| Pennsylvania | -7% | 1979 | 22 |
| Rhode Island | insufficient data | n/a | 2 |
| South Carolina | insufficient data | n/a | 3 |
| South Dakota | +19% | 1969 | 28 |
| Texas | -68% | 1981 | 10 |
| Utah | +128% | 1996 | 15 |
| Vermont | +828% | 1969 | 12 |
| Virginia | insufficient data | n/a | 4 |
| Washington | -76% | 1972 | 48 |
| West Virginia | insufficient data | n/a | 1 |
| Wisconsin | -32% | 1969 | 49 |
| Wyoming | +645% | 1979 | 28 |
Ring-billed Gull Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Northern Pacific Rainforest | -94% | 1974 | 30 |
| Great Basin | -11% | 1971 | 112 |
| Northern Rockies | +894% | 1971 | 52 |
| Prairie Potholes | +746% | 1969 | 91 |
| Boreal Hardwood Transition | -47% | 1969 | 74 |
| Lower Great Lakes / St. Lawrence Plain | 34× | 1968 | 60 |
| Atlantic Northern Forest | +959% | 1969 | 45 |
| Sierra Nevada | +202% | 1979 | 5 |
| Southern Rockies / Colorado Plateau | -75% | 1991 | 26 |
| Badlands and Prairies | +51% | 1970 | 39 |
| Shortgrass Prairie | -23% | 1974 | 17 |
| Central Mixed Grass Prairie | -97% | 1970 | 7 |
| Eastern Tallgrass Prairie | +487% | 1979 | 37 |
| Prairie Hardwood Transition | +154% | 1968 | 92 |
| Southeastern Coastal Plain | -93% | 1969 | 29 |
| Appalachian Mountains | 15× | 1972 | 31 |
| Piedmont | -93% | 1971 | 8 |
| New England / Mid-Atlantic Coast | -81% | 1968 | 76 |
| Peninsular Florida | -61% | 1977 | 12 |
| Coastal California | -95% | 1974 | 16 |
| Sonoran and Mojave Deserts | -89% | 1976 | 6 |
| Gulf Coastal Prairie | -77% | 1973 | 15 |
Ring-billed Gull Conservation Status
Our route-weighted index shows it up about 154% since 1968.
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.