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

Killdeer Population Trend in Delaware

All statesShorebirds

Killdeer in Delaware has surged: up 98% on the route-weighted index since 1968.

+98%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 →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Killdeer 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 →

Killdeer has surged in Delaware: up 98% on the route-weighted index since 1968.

Killdeer Population Forecast in Delaware

If the recent trend holds, Killdeer in Delaware is projected to stay roughly flat through 2029, near 5.7 (95% range 1.1–10). A 5-year backtest shows a typical error of ±22.7%, with 100% of held-out values landing inside the 95% band.

-5%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 →
5.7Projected 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 →
1.1–1095% 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 →
±22.7%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, Killdeer in Delaware is projected to stay roughly flat through 2029, near 5.7 (95% range 1.1–10). A 5-year backtest shows a typical error of ±22.7%, 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 →
20255.61.010
20265.61.110
20275.71.110
20285.71.110
20295.71.110

Killdeer Survey Routes in Delaware

Routes recording Killdeer 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 →
Millsboro1020242017
Lowes Xrds719911966
Holleyville 2720242006
Harrington620241966
Frederica620141967
Blackbird520241994
Milton420161966
Frankford320121966
Holleyville320041966
Bethany Bch319901967
Mt Pleasant220191967
Wilmington220121966
Dover219871966
Georgetown220221992
Milton 2220172017
Pepperbox 2220242017
Pepperbox120161998

Killdeer Population Trend in Other States

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

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