Black-and-white Warbler
Black-and-white Warbler has edged up: up 23% on the route-weighted index since 1968.
About the Black-and-white Warbler
The Black-and-white Warbler (Mniotilta varia) is a North American member of the Wood-Warblers (Parulidae). In this analysis it is grouped with the forest birds.
- Size
- 4.5–5.5 in long (11–14 cm) — a small, active songbird (typical for the family)
- Habitat
- Woodlands and forest edges, including wooded suburbs and parks.
- Diet
- Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
- Range
- Recorded on 1,505 Breeding Bird Survey routes across 36 states, most concentrated in the Appalachian Mountains.
- Family
- Parulidae · Forest birds
Notable Black-and-white Warbler Trends
No notable trend signals for Black-and-white Warbler. See the full index history below.
Black-and-white Warbler Population Forecast
If the recent trend holds, Black-and-white Warbler is projected to fall about 19% by 2029 — from 0.88 in 2024 to a central estimate of 0.71 (95% range 0.53–0.89). A 5-year backtest shows a typical error of ±16.2%, with 60% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.71 | 0.53 | 0.89 |
| 2026 | 0.71 | 0.53 | 0.89 |
| 2027 | 0.71 | 0.53 | 0.89 |
| 2028 | 0.71 | 0.53 | 0.89 |
| 2029 | 0.71 | 0.53 | 0.89 |
Where the Black-and-white Warbler Is Detected
BBS routes recording Black-and-white Warbler, sized by most recent count.
Black-and-white Warbler Population Trend by State
| Alabama | -16% | 1968 | 68 |
| Arkansas | +68% | 1969 | 50 |
| California | insufficient data | n/a | 1 |
| Connecticut | -42% | 1968 | 20 |
| Delaware | -44% | 1968 | 12 |
| Georgia | +428% | 1968 | 54 |
| Illinois | -83% | 1970 | 9 |
| Indiana | -57% | 1981 | 13 |
| Kansas | insufficient data | n/a | 3 |
| Kentucky | +17% | 1968 | 44 |
| Louisiana | +52% | 1969 | 36 |
| Maine | +111% | 1968 | 77 |
| Maryland | +3% | 1968 | 59 |
| Massachusetts | +20% | 1968 | 32 |
| Michigan | +422% | 1968 | 75 |
| Minnesota | +530% | 1969 | 51 |
| Mississippi | +247% | 1968 | 41 |
| Missouri | +255% | 1975 | 49 |
| Nebraska | -76% | 1982 | 6 |
| New Hampshire | -7% | 1968 | 26 |
| New Jersey | +46% | 1968 | 35 |
| New York | +44% | 1968 | 108 |
| North Carolina | +157% | 1969 | 84 |
| North Dakota | +925% | 1972 | 10 |
| Ohio | +515% | 1970 | 37 |
| Oklahoma | +319% | 1969 | 39 |
| Pennsylvania | +246% | 1968 | 112 |
| Rhode Island | +36% | 1968 | 5 |
| South Carolina | +661% | 1968 | 24 |
| Tennessee | -9% | 1968 | 44 |
| Texas | +150% | 1969 | 54 |
| Vermont | +168% | 1968 | 26 |
| Virginia | +83% | 1968 | 72 |
| West Virginia | +40% | 1968 | 59 |
| Wisconsin | +262% | 1968 | 69 |
| Wyoming | insufficient data | n/a | 1 |
Black-and-white Warbler Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Prairie Potholes | +563% | 1981 | 15 |
| Boreal Hardwood Transition | +351% | 1968 | 125 |
| Lower Great Lakes / St. Lawrence Plain | +168% | 1968 | 54 |
| Atlantic Northern Forest | +72% | 1968 | 155 |
| Badlands and Prairies | -74% | 1983 | 5 |
| Central Mixed Grass Prairie | -7% | 1998 | 13 |
| Edwards Plateau | 13× | 1985 | 9 |
| Oaks and Prairies | +221% | 1973 | 33 |
| Eastern Tallgrass Prairie | -64% | 1970 | 33 |
| Prairie Hardwood Transition | +216% | 1968 | 65 |
| Central Hardwoods | +62% | 1968 | 111 |
| West Gulf Coastal Plain / Ouachitas | +48% | 1969 | 97 |
| Mississippi Alluvial Valley | +93% | 1970 | 16 |
| Southeastern Coastal Plain | +387% | 1968 | 154 |
| Appalachian Mountains | +68% | 1968 | 371 |
| Piedmont | +581% | 1968 | 108 |
| New England / Mid-Atlantic Coast | -3% | 1968 | 138 |
Black-and-white Warbler Conservation Status
Our route-weighted index shows it up about 23% 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.