BirdAnalyst
Species · Delaware · BBS 2026 Release · 1966–2025

American Robin Population Trend in Delaware

All statesForest birds

American Robin in Delaware has risen sharply: up 59% on the route-weighted index since 1968.

+59%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 →
17Routes 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 American Robin 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 →

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 →

American Robin has risen sharply in Delaware: up 59% on the route-weighted index since 1968.

American Robin Population Forecast in Delaware

If the recent trend holds, American Robin in Delaware is projected to rise about 38% by 2030 — from 56 in 2025 to a central estimate of 77 (95% range 49–105). A 5-year backtest shows a typical error of ±80.7%, with 0% of held-out values landing inside the 95% band.

+38%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 →
77Projected 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 →
49–10595% 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 →
±80.7%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, American Robin in Delaware is projected to rise about 38% by 2030 — from 56 in 2025 to a central estimate of 77 (95% range 49–105). A 5-year backtest shows a typical error of ±80.7%, with 0% 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 →
20267547103
20277547103
20287648104
20297749105
20307749105

American Robin Survey Routes in Delaware

Routes recording American Robin 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 →
Frederica8920251966
Milton8920161966
Milton 28320252017
Harrington7620251966
Mt Pleasant7120191966
Frankford6820121966
Holleyville 26820242006
Holleyville6320041966
Bethany Bch4519901966
Dover3719871966
Georgetown3720221992
Pepperbox 23720252017
Lowes Xrds3219911966
Blackbird3120251994
Pepperbox2820161998
Wilmington2020141966
Millsboro2020252017

American Robin Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutfloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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