BirdAnalyst
Species · BCR 28 · BBS 2025 Release · 1966–2024

Henslow's Sparrow In Appalachian Mountains

All regionsAppalachian MountainsGrassland birds

Henslow's Sparrow in Appalachian Mountains has collapsed: down 95% on the route-weighted index since 1968.

-95%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 →
69Routes 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 →
55YearsYears 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 →

Henslow's Sparrow has collapsed in Appalachian Mountains: down 95% on the route-weighted index since 1968.

Henslow's Sparrow In Appalachian Mountains Population Forecast

If the recent trend holds, Henslow's Sparrow in Appalachian Mountains is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.05). A 5-year backtest shows a typical error of ±322.2%, with 100% of held-out values landing inside the 95% band.

n/aChange 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 →
0.00–0.0595% 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 →
±322.2%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, Henslow's Sparrow in Appalachian Mountains is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.05). A 5-year backtest shows a typical error of ±322.2%, with 100% 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 →
20240.000.000.05
20250.000.000.05
20260.000.000.05
20270.000.000.05
20280.000.000.05

Routes In Appalachian Mountains

Routes recording Henslow's Sparrow in Appalachian Mountains.
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 →
LisleNEW-YORK72003
RasselasPENNSYLVANIA52004
WakenaPENNSYLVANIA42000
MeadowbrookOHIO32016
Coal RunOHIO31990
SigelPENNSYLVANIA31999
BebeeWEST-VIRGINIA31975
MedusaNEW-YORK21969
Phillips CrNEW-YORK22006
SwainNEW-YORK21983
NewcomerstwnOHIO21984
RayOHIO21998
OmegaOHIO22023
CumberlandOHIO21998
SheloctaPENNSYLVANIA21995
MunsonPENNSYLVANIA22001
FinzelMARYLAND12021
AccidentMARYLAND11994
SomersNEW-YORK11975
DurhamNEW-YORK11969
LaurensNEW-YORK11981
Whitney PtNEW-YORK11972
CoventryvileNEW-YORK11978
CorbettsvileNEW-YORK11986
E NewarkNEW-YORK11993

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