BirdAnalyst
Species · BCR 18 · BBS 2025 Release · 1966–2024

Loggerhead Shrike In Shortgrass Prairie

All regionsShortgrass PrairieGeneralists

Loggerhead Shrike in Shortgrass Prairie has fallen sharply: down 61% on the route-weighted index since 1969.

-61%Since 1969TrendPercent 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 →
126Routes 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 →
57YearsYears 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 declinecomputed 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 →

Loggerhead Shrike has fallen sharply in Shortgrass Prairie: down 60% on the route-weighted index since 1969.

Loggerhead Shrike In Shortgrass Prairie Population Forecast

If the recent trend holds, Loggerhead Shrike in Shortgrass Prairie is projected to stay roughly flat through 2029, near 1.2 (95% range 0.12–2.4). A 5-year backtest shows a typical error of ±39.6%, with 100% of held-out values landing inside the 95% band.

+9%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 →
1.2Projected 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 →
0.12–2.495% 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 →
±39.6%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, Loggerhead Shrike in Shortgrass Prairie is projected to stay roughly flat through 2029, near 1.2 (95% range 0.12–2.4). A 5-year backtest shows a typical error of ±39.6%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20251.30.192.4
20261.30.172.4
20271.30.152.4
20281.30.132.4
20291.20.122.4

Routes In Shortgrass Prairie

Routes recording Loggerhead Shrike in Shortgrass Prairie.
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 →
PecosTEXAS192017
CrowleyCOLORADO162024
GruverTEXAS152016
Prospect ValCOLORADO142000
Adams Co.COLORADO112022
BennettCOLORADO92018
MaljamarNEW-MEXICO81977
VariaderoNEW-MEXICO82022
ChugwaterWYOMING82024
RushCOLORADO72022
Mica ButteCOLORADO71987
BethuneCOLORADO72016
WinkTEXAS71986
Last Chance 2COLORADO62024
LoganNEW-MEXICO62023
WaverlyCOLORADO52018
Doyle BridgeCOLORADO51997
DaltonNEBRASKA52024
BoyeroCOLORADO42017
VillegreenCOLORADO42024
CaprockNEW-MEXICO42024
SkellytownTEXAS42009
CactusTEXAS41994
SaragosaTEXAS42024
BriggsdaleCOLORADO32024

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