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

Savannah Sparrow Population Trend in Connecticut

All statesGrassland birds

Savannah Sparrow in Connecticut has edged down: down 12% on the route-weighted index since 1975.

-12%Since 1975TrendPercent 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 →
9Routes 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 →
28YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Savannah Sparrow Trends in ConnecticutNotable 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 Savannah Sparrow in Connecticut. See the full index history below.

Savannah Sparrow Population Forecast in Connecticut

If the recent trend holds, Savannah Sparrow in Connecticut is projected to fall about 27% by 2027 — from 0.36 in 2022 to a central estimate of 0.27 (95% range 0.00–0.58). A 5-year backtest shows a typical error of ±154.4%, with 100% of held-out values landing inside the 95% band.

-27%Change by 2027TrendPercent 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 →
0.27Projected 2027 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.5895% 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 →
±154.4%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, Savannah Sparrow in Connecticut is projected to fall about 27% by 2027 — from 0.36 in 2022 to a central estimate of 0.27 (95% range 0.00–0.58). A 5-year backtest shows a typical error of ±154.4%, with 100% of held-out values landing inside the 95% band.19672027
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 →
20230.260.000.58
20240.260.000.58
20250.260.000.58
20260.260.000.58
20270.270.000.58

Savannah Sparrow Survey Routes in Connecticut

Routes recording Savannah Sparrow in Connecticut.
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 →
Mystic219801980
Buckingham220222007
Uncasville220221991
Willimantic220071996
No Woodbury120111967
Sherman120161976
Warren119931993
Southington119811981
New Hartford119731973

Savannah Sparrow Population Trend in Other States

alaskaarizonacaliforniacoloradodelawareidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooregonpennsylvaniarhode-islandsouth-dakotatennesseeutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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