Marbled Murrelet
Marbled Murrelet has surged: up 31× on the route-weighted index since 1977.
About the Marbled Murrelet
The Marbled Murrelet (Brachyramphus marmoratus) is a North American member of the Auks, Murres & Puffins (Alcidae). In this analysis it is grouped with the seabirds.
- Size
- 8–17.5 in long (20–45 cm) — a compact seabird (typical for the family)
- Habitat
- Open ocean and coastlines, coming ashore mainly to nest in colonies.
- Diet
- Fish, squid and other marine animals caught at or below the surface.
- Range
- Recorded on 40 Breeding Bird Survey routes across 4 states, most concentrated in the Northern Pacific Rainforest.
- Family
- Alcidae · Seabirds
Notable Marbled Murrelet Trends
No notable trend signals for Marbled Murrelet. See the full index history below.
Marbled Murrelet Population Forecast
If the recent trend holds, Marbled Murrelet is projected to fall about 43% by 2029 — from 0.08 in 2024 to a central estimate of 0.05 (95% range 0.00–0.13). A 5-year backtest shows a typical error of ±91.8%, with 100% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.05 | 0.00 | 0.13 |
| 2026 | 0.05 | 0.00 | 0.13 |
| 2027 | 0.05 | 0.00 | 0.13 |
| 2028 | 0.05 | 0.00 | 0.13 |
| 2029 | 0.05 | 0.00 | 0.13 |
Where the Marbled Murrelet Is Detected
BBS routes recording Marbled Murrelet, sized by most recent count.
Marbled Murrelet Population Trend by State
| Alaska | +97% | 1977 | 26 |
| California | +14% | 1985 | 6 |
| Oregon | insufficient data | n/a | 4 |
| Washington | -88% | 1987 | 4 |
Marbled Murrelet Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| Northern Pacific Rainforest | 26× | 1977 | 36 |
Marbled Murrelet Conservation Status
Our route-weighted index shows it up about 3045% since 1977.
Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.