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Species · Tennessee · BBS 2025 Release · 1966–2024

Grasshopper Sparrow Population Trend in Tennessee

All statesGrassland birds

Grasshopper Sparrow in Tennessee has collapsed: down 89% on the route-weighted index since 1968.

-89%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 →
35Routes 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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Grasshopper Sparrow 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 →

Grasshopper Sparrow has collapsed in Tennessee: down 89% on the route-weighted index since 1968.

Grasshopper Sparrow Population Forecast in Tennessee

If the recent trend holds, Grasshopper Sparrow in Tennessee is projected to rise about 278% by 2029 — from 0.09 in 2024 to a central estimate of 0.34 (95% range 0.00–0.95). A 5-year backtest shows a typical error of ±275.1%, with 100% of held-out values landing inside the 95% band.

+278%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 →
0.34Projected 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 →
0.00–0.9595% 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 →
±275.1%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, Grasshopper Sparrow in Tennessee is projected to rise about 278% by 2029 — from 0.09 in 2024 to a central estimate of 0.34 (95% range 0.00–0.95). A 5-year backtest shows a typical error of ±275.1%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20250.380.000.99
20260.370.000.98
20270.360.000.97
20280.350.000.96
20290.340.000.95

Grasshopper Sparrow Survey Routes in Tennessee

Routes recording Grasshopper Sparrow 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 →
Campbellsville419921967
Allens Brdge420231966
Belotes Bend319911966
Corryton Rd320191966
Pawpaw 2320172013
Tiptonville220092007
Sweetlips220171972
Petersburg220131982
Glen220241966
Climer220041967
Jefferson Cty220111966
Pawpaw120111982
Jones Gap120192001
Brownsville120042003
Tibbs120071980
Whiteville120071988
Big Sandy120162002
Mansfield120141981
Silerton119991990
Newfound Gap119911991
Humboldt119711968
Indian Mound119781978
Collinwood120041969
Wrigley119941979
Lewis Forest120091966

Grasshopper Sparrow Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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