Blue-gray Gnatcatcher Population Analysis
Blue-gray Gnatcatcher has surged: up 157% on the route-weighted index since 1968.
About the Blue-gray Gnatcatcher
The Blue-gray Gnatcatcher (Polioptila caerulea) is a North American member of the Gnatcatchers (Polioptilidae). In this analysis it is grouped with the forest birds.
- Size
- 4–5 in long (10–13 cm) — a tiny, long-tailed 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 2,545 Breeding Bird Survey routes across 45 states, most concentrated in the Appalachian Mountains.
- Family
- Polioptilidae · Forest birds
Notable Blue-gray Gnatcatcher TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →
Blue-gray Gnatcatcher has surged in surveyed states: up 156% on the route-weighted index since 1968.
Blue-gray Gnatcatcher Population Forecast
If the recent trend holds, Blue-gray Gnatcatcher is projected to rise about 13% by 2030 — from 3.1 in 2025 to a central estimate of 3.5 (95% range 3.0–4.0). A 5-year backtest shows a typical error of ±16.8%, with 40% of held-out values landing inside the 95% band.
Where the Blue-gray Gnatcatcher Is Detected
BBS routes recording Blue-gray Gnatcatcher, sized by most recent count.
Blue-gray Gnatcatcher Population Trend by State
Blue-gray Gnatcatcher Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
Blue-gray Gnatcatcher Conservation Status
Our route-weighted index shows it up about 156% since 1968.
Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14. Trend is a route-weighted relative-abundance index, not an absolute population.