BirdAnalyst
Species · BCR 4 · BBS 2025 Release · 1966–2024

Common Raven In BCR 4

All regionsBCR 4Generalists

Common Raven in BCR 4 has risen sharply: up 64% on the route-weighted index since 1978.

+64%Since 1978TrendPercent 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 →
67Routes 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 →
45YearsYears 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 →

Common Raven has risen sharply in BCR 4: up 64% on the route-weighted index since 1978.

Forecast

If the recent trend holds, Common Raven in BCR 4 is projected to rise about 23% by 2029 — from 3.4 in 2024 to a central estimate of 4.2 (95% range 1.1–7.2). A 5-year backtest shows a typical error of ±23.4%, with 100% of held-out values landing inside the 95% band.

+23%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 →
4.2Projected 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 →
1.1–7.295% 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 →
±23.4%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, Common Raven in BCR 4 is projected to rise about 23% by 2029 — from 3.4 in 2024 to a central estimate of 4.2 (95% range 1.1–7.2). A 5-year backtest shows a typical error of ±23.4%, 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 →
20254.11.07.1
20264.11.07.1
20274.11.17.2
20284.11.17.2
20294.21.17.2

Routes In BCR 4

Routes recording Common Raven in BCR 4.
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 →
KachemakALASKA132024
Galena (Short)ALASKA122024
RubyALASKA112024
Nicholai SlALASKA92024
HomerALASKA81982
KalifonskyALASKA82023
ColdfootALASKA82024
Tangle LakesALASKA81987
NorthwayALASKA72023
SourdoughALASKA72024
SlanaALASKA62024
Bear CreekALASKA61991
PetersvilleALASKA62024
WillowALASKA52022
Chena RiverALASKA51988
Swan Lake RdALASKA52023
Hather CreekALASKA52019
DeltaALASKA52024
MonahanALASKA42021
ChickenALASKA42024
Anchor RiverALASKA42024
Lake LouiseALASKA42012
Burma RoadALASKA42024
Caribou Mtn.ALASKA42024
TatalinaALASKA42019

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22.