Blue Grosbeak
Blue Grosbeak has risen sharply: up 64% on the route-weighted index since 1968.
About the Blue Grosbeak
The Blue Grosbeak (Passerina caerulea) is a North American member of the Cardinals & Grosbeaks (Cardinalidae). In this analysis it is grouped with the forest birds.
- Size
- 4.5–8.5 in long (12–22 cm) — a medium 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 2,079 Breeding Bird Survey routes across 38 states, most concentrated in the Southeastern Coastal Plain.
- Family
- Cardinalidae · Forest birds
Notable Blue Grosbeak 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 Grosbeak has risen sharply in surveyed states: up 64% on the route-weighted index since 1968.
Blue Grosbeak Population Forecast
If the recent trend holds, Blue Grosbeak is projected to stay roughly flat through 2029, near 2.6 (95% range 2.2–2.9). A 5-year backtest shows a typical error of ±3.2%, with 100% of held-out values landing inside the 95% band.
Where the Blue Grosbeak Is Detected
BBS routes recording Blue Grosbeak, sized by most recent count.
Blue Grosbeak Population Trend by State
Blue Grosbeak Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
Blue Grosbeak Conservation Status
Our route-weighted index shows it up about 64% 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.