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Species · Maryland · BBS 2026 Release · 1966–2025

Seaside Sparrow Population Trend in Maryland

All statesWetland birds

Seaside Sparrow in Maryland has surged: up 80% on the route-weighted index since 1968.

+80%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 →
3Routes 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 →
59YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Seaside Sparrow Trends in MarylandNotable 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 increasecomputed 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 →

Seaside Sparrow has surged in Maryland: up 80% on the route-weighted index since 1968.

Seaside Sparrow Population Forecast in Maryland

If the recent trend holds, Seaside Sparrow in Maryland is projected to fall about 27% by 2030 — from 0.60 in 2025 to a central estimate of 0.44 (95% range 0.18–0.70). A 5-year backtest shows a typical error of ±21.2%, with 100% of held-out values landing inside the 95% band.

-27%Change by 2030TrendPercent 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 →
0.44Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.18–0.7095% 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 →
±21.2%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, Seaside Sparrow in Maryland is projected to fall about 27% by 2030 — from 0.60 in 2025 to a central estimate of 0.44 (95% range 0.18–0.70). A 5-year backtest shows a typical error of ±21.2%, with 100% of held-out values landing inside the 95% band.19662030
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 →
20260.440.180.70
20270.440.180.70
20280.440.180.70
20290.440.180.70
20300.440.180.70

Seaside Sparrow Survey Routes in Maryland

Routes recording Seaside Sparrow in Maryland.
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 →
Madison1320251966
Honga920251966
Cokesbury120251968

Seaside Sparrow Population Trend in Other States

alabamadelawarefloridalouisianamassachusettsnew-jerseynew-yorknorth-carolinasouth-carolinatexasvirginia

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.