BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Loggerhead Shrike In Northern Rockies

All regionsNorthern RockiesGeneralists

Loggerhead Shrike in Northern Rockies has increased: up 42% on the route-weighted index since 1970.

+42%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 →
74Routes 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 →
56YearsYears 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 →

No notable trend signals for Loggerhead Shrike in Northern Rockies. See the full index history below.

Forecast

If the recent trend holds, Loggerhead Shrike in Northern Rockies is projected to fall about 45% by 2029 — from 0.53 in 2024 to a central estimate of 0.29 (95% range 0.00–0.61). A 5-year backtest shows a typical error of ±21.9%, with 100% of held-out values landing inside the 95% band.

-45%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 →
0.29Projected 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 →
0.00–0.6195% 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 →
±21.9%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, Loggerhead Shrike in Northern Rockies is projected to fall about 45% by 2029 — from 0.53 in 2024 to a central estimate of 0.29 (95% range 0.00–0.61). A 5-year backtest shows a typical error of ±21.9%, 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 →
20250.290.000.61
20260.290.000.61
20270.290.000.61
20280.290.000.61
20290.290.000.61

Routes In Northern Rockies

Routes recording Loggerhead Shrike in Northern Rockies.
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 →
ArmintoWYOMING102024
BaggsWYOMING92024
RelianceWYOMING72018
Flamin GorgeWYOMING62024
MadrasOREGON52024
FrannieWYOMING52023
Gas HillsWYOMING52012
WamsutterWYOMING52024
Rawlins 2WYOMING52023
ClarkWYOMING42024
RawlinsWYOMING42014
Carter 2WYOMING42024
Bear CreekWYOMING32018
CumberlandWYOMING32024
LysiteWYOMING32017
WorlandWYOMING32024
PathfinderWYOMING32024
ShirleyWYOMING32022
Patrick Draw 2WYOMING31982
Gas Hills 2WYOMING32024
MaybellCOLORADO22024
Great DivideCOLORADO22018
Browns ParkCOLORADO22024
LimaMONTANA22024
GreenoughMONTANA21996

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