BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Saltmarsh Sparrow

PasserellidaeWetland birdsAmmospiza caudacuta

Saltmarsh Sparrow has collapsed: down 91% on the route-weighted index since 1968.

-91%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 →
14RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
33Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Saltmarsh Sparrow

The Saltmarsh Sparrow (Ammospiza caudacuta) is a North American member of the New World Sparrows (Passerellidae). In this analysis it is grouped with the wetland birds.

Size
4.5–7.5 in long (12–19 cm) — a small songbird (typical for the family)
Habitat
Marshes, ponds, lakeshores and other freshwater wetlands.
Diet
Aquatic invertebrates, small fish, frogs and plant matter.
Range
Recorded on 14 Breeding Bird Survey routes across 7 states, most concentrated in the New England / Mid-Atlantic Coast.
Family
Passerellidae · Wetland birds

Notable Saltmarsh Sparrow TrendsNotable 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 Saltmarsh Sparrow. See the full index history below.

Saltmarsh Sparrow Population Forecast

If the recent trend holds, Saltmarsh Sparrow is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.01). A 5-year backtest shows a typical error of ±71.2%, 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 →
0.00–0.0195% 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 →
±71.2%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, Saltmarsh Sparrow is projected to stay roughly flat through 2028, near 0.00 (95% range 0.00–0.01). A 5-year backtest shows a typical error of ±71.2%, 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 →
20240.000.000.01
20250.000.000.01
20260.000.000.01
20270.000.000.01
20280.000.000.01

Where the Saltmarsh Sparrow Is Detected

BBS routes recording Saltmarsh Sparrow, sized by most recent count.

Saltmarsh Sparrow Population Trend by State

Saltmarsh Sparrow population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Delawareinsufficient datan/a4
Marylandinsufficient datan/a2
Massachusettsinsufficient datan/a1
New Jerseyinsufficient datan/a1
New Yorkinsufficient datan/a3
Rhode Islandinsufficient datan/a2
Virginiainsufficient datan/a1

Saltmarsh Sparrow Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Saltmarsh Sparrow population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
New England / Mid-Atlantic Coast-68%196814

Saltmarsh Sparrow Conservation Status

Our route-weighted index shows it down about 91% since 1968.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.