BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Yellow-billed Magpie

CorvidaeGeneralistsPica nuttalli

Yellow-billed Magpie has declined: down 29% on the route-weighted index since 1970.

-29%Since 1970TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
49RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
56Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Yellow-billed Magpie

The Yellow-billed Magpie (Pica nuttalli) is a North American member of the Crows, Jays & Magpies (Corvidae). In this analysis it is grouped with the generalists.

Size
10–27.5 in long (25–70 cm) — a medium to large songbird (typical for the family)
Habitat
A broad range of open and wooded habitats, often near people.
Diet
An opportunistic mix of insects, seeds, fruit and scraps.
Range
Recorded on 49 Breeding Bird Survey routes across 1 state, most concentrated in the Coastal California.
Family
Corvidae · Generalists

Notable Yellow-billed Magpie TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Yellow-billed Magpie. See the full index history below.

Yellow-billed Magpie Population Forecast

If the recent trend holds, Yellow-billed Magpie is projected to fall about 89% by 2029 — from 0.06 in 2024 to a central estimate of 0.01 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±25.2%, with 100% of held-out values landing inside the 95% band.

-89%Change by 2029TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →
0.01Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.2095% range95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
±25.2%Backtest errorBacktest errorTypical error when we hold out the most recent years, forecast them, and compare to what actually happened. Lower means a more trustworthy projection.Full methodology →
If the recent trend holds, Yellow-billed Magpie is projected to fall about 89% by 2029 — from 0.06 in 2024 to a central estimate of 0.01 (95% range 0.00–0.20). A 5-year backtest shows a typical error of ±25.2%, with 100% of held-out values landing inside the 95% band.19682029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →95% low95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →95% high95% rangeThe 95% uncertainty band around the projection at the forecast horizon. The true value should land inside it most of the time.Full methodology →
20250.030.000.23
20260.030.000.22
20270.020.000.22
20280.010.000.21
20290.010.000.20

Where the Yellow-billed Magpie Is Detected

BBS routes recording Yellow-billed Magpie, sized by most recent count.

Yellow-billed Magpie Population Trend by State

Yellow-billed Magpie population trend by state.
TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
California-40%197049

Yellow-billed Magpie Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Yellow-billed Magpie population trend by Bird Conservation Region.
TrendPercent change in the route-weighted abundance index between a smoothed baseline window and the most recent one. It tracks direction, not absolute population.Full methodology →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Coastal California-34%197047

Yellow-billed Magpie Conservation Status

Our route-weighted index shows it down about 29% since 1970.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.