BirdAnalyst
Species · New York · BBS 2025 Release · 1966–2024

Cliff Swallow Population Trend in New York

All statesAerial insectivores

Cliff Swallow in New York has collapsed: down 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 →
92Routes 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 Cliff Swallow Trends in New YorkNotable 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 →

Cliff Swallow has collapsed in New York: down 80% on the route-weighted index since 1968.

Cliff Swallow Population Forecast in New York

If the recent trend holds, Cliff Swallow in New York is projected to rise about 17× by 2029 — from 0.06 in 2024 to a central estimate of 0.96 (95% range 0.07–1.9). A 5-year backtest shows a typical error of ±635.6%, with 20% of held-out values landing inside the 95% band.

17×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 →
0.96Projected 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 →
0.07–1.995% 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 →
±635.6%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, Cliff Swallow in New York is projected to rise about 17× by 2029 — from 0.06 in 2024 to a central estimate of 0.96 (95% range 0.07–1.9). A 5-year backtest shows a typical error of ±635.6%, with 20% 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 →
20250.990.091.9
20260.990.091.9
20270.980.081.9
20280.970.071.9
20290.960.071.9

Cliff Swallow Survey Routes in New York

Routes recording Cliff Swallow in New York.
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 →
West Bangor3719981990
Downsville1620191982
Waddington1219981981
S Vandalia1220171974
Willsboro1020021968
North Easton820171971
Purdy820222000
E Newark719991975
Nashville720181967
Byron720071975
Middletown619801967
Cobleskill620161966
Dryden620071981
Dannemora619781968
Naples620232023
Platte Cove520171970
Laurens520171969
Swain520071985
Cherry Hill519981968
Oneida520101968
W Shokan420031968
Branchport420231996
East Java420191969
Ogdensburg420161979
Dexter Lake419751969

Cliff Swallow Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniasouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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