BirdAnalyst
Species · BCR 30 · BBS 2025 Release · 1966–2024

Saltmarsh Sparrow In New England / Mid-Atlantic Coast

All regionsNew England / Mid-Atlantic CoastGeneralists

Saltmarsh Sparrow in New England / Mid-Atlantic Coast has fallen sharply: down 68% on the route-weighted index since 1968.

-68%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 →
14Routes 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 →
33YearsYears 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 →

Saltmarsh Sparrow has fallen sharply in New England / Mid-Atlantic Coast: down 68% on the route-weighted index since 1968.

Saltmarsh Sparrow In New England / Mid-Atlantic Coast Population Forecast

If the recent trend holds, Saltmarsh Sparrow in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2028, near 0.05 (95% range 0.00–0.11). A 5-year backtest shows a typical error of ±138.1%, with 80% 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 →
0.05Projected 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 →
0.00–0.1195% 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 →
±138.1%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, Saltmarsh Sparrow in New England / Mid-Atlantic Coast is projected to stay roughly flat through 2028, near 0.05 (95% range 0.00–0.11). A 5-year backtest shows a typical error of ±138.1%, with 80% 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 →
20240.040.000.11
20250.050.000.11
20260.050.000.11
20270.050.000.11
20280.050.000.11

Routes In New England / Mid-Atlantic Coast

Routes recording Saltmarsh Sparrow in New England / Mid-Atlantic Coast.
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 →
Bethany BchDELAWARE51966
HongaMARYLAND31969
HarringtonDELAWARE22023
NewburyportMASSACHUSETTS22007
DoverDELAWARE11974
Lowes XrdsDELAWARE11978
CokesburyMARYLAND11997
Ocean CityNEW-JERSEY11986
WesthamptonNEW-YORK12006
HuntingtonNEW-YORK11995
Jones BeachNEW-YORK11995
Sachuest PtRHODE-ISLAND11978
Block IslandRHODE-ISLAND11989
Chincoteag WVIRGINIA12012

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