BirdAnalyst
Species · Tennessee · BBS 2025 Release · 1966–2024

Loggerhead Shrike Population Trend in Tennessee

All statesGeneralists

Loggerhead Shrike in Tennessee has collapsed: down 96% on the route-weighted index since 1968.

-96%Since 1968TrendPercent 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 →
37Routes In StateSurvey 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 Loggerhead Shrike Trends in TennesseeNotable 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 collapsed in Tennessee: down 96% on the route-weighted index since 1968.

Loggerhead Shrike Population Forecast in Tennessee

If the recent trend holds, Loggerhead Shrike in Tennessee is projected to fall about 100% by 2028 — from 0.20 in 2023 to a central estimate of 0.00 (95% range 0.00–0.89). A 5-year backtest shows a typical error of ±1275.4%, with 60% of held-out values landing inside the 95% band.

-100%Change by 2028TrendPercent 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 →
0.00Projected 2028 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.8995% 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 →
±1275.4%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, Loggerhead Shrike in Tennessee is projected to fall about 100% by 2028 — from 0.20 in 2023 to a central estimate of 0.00 (95% range 0.00–0.89). A 5-year backtest shows a typical error of ±1275.4%, with 60% of held-out values landing inside the 95% band.19662028
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 →
20240.000.000.89
20250.000.000.89
20260.000.000.89
20270.000.000.89
20280.000.000.89

Loggerhead Shrike Survey Routes in Tennessee

Routes recording Loggerhead Shrike in Tennessee.
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 →
Trenton919901966
Pawpaw 2620232014
Tullahoma519991967
Moscow419971966
Smokey Jct419971967
Tibbs320091966
Sweetlips220031966
Humboldt219891966
Collinwood220141966
White House219961966
Corryton Rd219881966
Mt Olive219951966
Allens Brdge219941968
Tiptonville120081966
Pawpaw120121966
Brownsville120051966
Whiteville119991966
Big Sandy119951966
Mansfield119941966
Silerton119911966
Pond Creek119931966
Indian Mound119831966
Wrigley120071966
Campbellsville120151966
Lewis Forest119991966

Loggerhead Shrike Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradofloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmichiganminnesotamississippimissourimontananebraskanevadanew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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