Winter Wren
Winter Wren has risen sharply: up 66% on the route-weighted index since 1968.
About the Winter Wren
The Winter Wren (Troglodytes hiemalis) is a North American member of the Wrens (Troglodytidae). In this analysis it is grouped with the forest birds.
- Size
- 4–8.5 in long (10–22 cm) — a small, energetic 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 488 Breeding Bird Survey routes across 17 states, most concentrated in the Atlantic Northern Forest.
- Family
- Troglodytidae · Forest birds
Notable Winter Wren Trends
Winter Wren has risen sharply in surveyed states: up 66% on the route-weighted index since 1968.
Winter Wren Population Forecast
If the recent trend holds, Winter Wren is projected to rise about 45% by 2029 — from 0.25 in 2024 to a central estimate of 0.36 (95% range 0.13–0.60). A 5-year backtest shows a typical error of ±63.2%, with 100% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.35 | 0.12 | 0.59 |
| 2026 | 0.35 | 0.12 | 0.59 |
| 2027 | 0.36 | 0.12 | 0.59 |
| 2028 | 0.36 | 0.12 | 0.59 |
| 2029 | 0.36 | 0.13 | 0.60 |
Where the Winter Wren Is Detected
BBS routes recording Winter Wren, sized by most recent count.
Winter Wren Population Trend by State
| Connecticut | +32% | 1973 | 15 |
| Maine | +8% | 1968 | 76 |
| Maryland | +48% | 1993 | 6 |
| Massachusetts | +283% | 1969 | 20 |
| Michigan | +541% | 1968 | 59 |
| Minnesota | +444% | 1969 | 34 |
| New Hampshire | +60% | 1968 | 26 |
| New Jersey | insufficient data | n/a | 1 |
| New York | +482% | 1968 | 80 |
| North Carolina | -50% | 1979 | 9 |
| Ohio | insufficient data | n/a | 1 |
| Pennsylvania | 13× | 1976 | 58 |
| Tennessee | 16× | 1976 | 4 |
| Vermont | +355% | 1968 | 26 |
| Virginia | -18% | 1983 | 10 |
| West Virginia | +345% | 1975 | 14 |
| Wisconsin | +99% | 1968 | 49 |
Winter Wren Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Boreal Hardwood Transition | +252% | 1968 | 117 |
| Lower Great Lakes / St. Lawrence Plain | +784% | 1972 | 36 |
| Atlantic Northern Forest | +107% | 1968 | 153 |
| Prairie Hardwood Transition | -17% | 1971 | 24 |
| Appalachian Mountains | 25× | 1971 | 125 |
| New England / Mid-Atlantic Coast | +108% | 1971 | 32 |
Winter Wren Conservation Status
Our route-weighted index shows it up about 66% 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.