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Species · BCR 2 · BBS 2026 Release · 1966–2025

Northern Shrike In BCR 2

All regionsBCR 2Grassland birds

Northern Shrike in BCR 2 has surged: up 94% on the route-weighted index since 1991.

+94%Since 1991TrendPercent 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 →
11Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
19YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

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

long arc increasecomputed indexTrend sourceWhether the figure is our own computed route-weighted index or an official USGS modeled estimate. The current build labels every trend as computed.Full methodology →

Northern Shrike has surged in BCR 2: up 94% on the route-weighted index since 1991.

Northern Shrike In BCR 2 Population Forecast

If the recent trend holds, Northern Shrike in BCR 2 is projected to fall about 67% by 2030 — from 1.5 in 2025 to a central estimate of 0.50 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±74.6%, with 20% of held-out values landing inside the 95% band.

-67%Change by 2030TrendPercent 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 →
0.50Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1.295% 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 →
±74.6%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, Northern Shrike in BCR 2 is projected to fall about 67% by 2030 — from 1.5 in 2025 to a central estimate of 0.50 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±74.6%, with 20% of held-out values landing inside the 95% band.19852030
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 →
20260.460.001.1
20270.470.001.2
20280.480.001.2
20290.490.001.2
20300.500.001.2

Routes In BCR 2

Routes recording Northern Shrike in BCR 2.
Recent countThe raw number of individuals recorded on this route in its most recent survey year. A single-route tally, not a trend.Full methodology →
Cold BayALASKA52025
King SalmonALASKA22025
TellerALASKA22017
Katmai N.P.ALASKA12025
ChiniakALASKA12022
Kodiak 2ALASKA11991
CouncilALASKA12008
NomeALASKA12023
Salmon LakeALASKA12017
KotzebueALASKA12025
Cold Bay (Short)ALASKA11990

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.