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

Bank Swallow Population Trend in Delaware

All statesAerial insectivores

Bank Swallow in Delaware has held roughly steady: up 10% on the route-weighted index since 1969.

+10%Since 1969TrendPercent 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 →
8Routes 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 →
39YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Bank Swallow Trends in DelawareNotable 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 Bank Swallow in Delaware. See the full index history below.

Bank Swallow Population Forecast in Delaware

If the recent trend holds, Bank Swallow in Delaware is projected to rise about 688% by 2029 — from 0.20 in 2024 to a central estimate of 1.6 (95% range 0.00–5.3). A 5-year backtest shows a typical error of ±350.3%, with 100% of held-out values landing inside the 95% band.

+688%Change by 2029TrendPercent 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 →
1.6Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–5.395% 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 →
±350.3%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, Bank Swallow in Delaware is projected to rise about 688% by 2029 — from 0.20 in 2024 to a central estimate of 1.6 (95% range 0.00–5.3). A 5-year backtest shows a typical error of ±350.3%, with 100% of held-out values landing inside the 95% band.19662029
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 →
20251.60.005.3
20261.60.005.3
20271.60.005.3
20281.60.005.3
20291.60.005.3

Bank Swallow Survey Routes in Delaware

Routes recording Bank Swallow in Delaware.
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 →
Mt Pleasant1220151984
Holleyville620031995
Milton419691969
Blackbird220032003
Wilmington119681966
Harrington120241968
Frederica119751975
Lowes Xrds119751972

Bank Swallow Population Trend in Other States

alabamaalaskaarkansascaliforniacoloradoconnecticutidahoillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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