BirdAnalyst
Species · BCR 33 · BBS 2026 Release · 1966–2025

Barn Swallow In Sonoran and Mojave Deserts

All regionsSonoran and Mojave DesertsAerial insectivores

Barn Swallow in Sonoran and Mojave Deserts has surged: up 102% on the route-weighted index since 1970.

+102%Since 1970TrendPercent 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 →
55Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 →

Barn Swallow has surged in Sonoran and Mojave Deserts: up 102% on the route-weighted index since 1970.

Barn Swallow In Sonoran and Mojave Deserts Population Forecast

If the recent trend holds, Barn Swallow in Sonoran and Mojave Deserts is projected to fall about 63% by 2030 — from 2.3 in 2025 to a central estimate of 0.86 (95% range 0.00–2.3). A 5-year backtest shows a typical error of ±324.5%, with 80% of held-out values landing inside the 95% band.

-63%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 →
0.86Projected 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 →
0.00–2.395% 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 →
±324.5%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, Barn Swallow in Sonoran and Mojave Deserts is projected to fall about 63% by 2030 — from 2.3 in 2025 to a central estimate of 0.86 (95% range 0.00–2.3). A 5-year backtest shows a typical error of ±324.5%, with 80% of held-out values landing inside the 95% band.19682030
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 →
20260.850.002.3
20270.850.002.3
20280.850.002.3
20290.860.002.3
20300.860.002.3

Routes In Sonoran and Mojave Deserts

Routes recording Barn Swallow in Sonoran and Mojave Deserts.
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 →
NilandCALIFORNIA552025
BlytheCALIFORNIA201979
Alamo RiverCALIFORNIA122018
Ajo 2ARIZONA82013
Palo VerdeCALIFORNIA72025
GoldstoneCALIFORNIA51998
CimaCALIFORNIA51972
DatelandARIZONA42021
Haiwee ResCALIFORNIA42005
LagunaARIZONA32023
AntaresARIZONA32018
Palo VerdeARIZONA32013
HopeARIZONA32009
Cutter 2ARIZONA32017
New RiverARIZONA22016
Cibola LakeARIZONA22012
ArabyARIZONA22018
Willow BeachARIZONA21989
Casa GrandeARIZONA22001
BarstowCALIFORNIA21996
Death ValleyCALIFORNIA21994
Kelso ValleyCALIFORNIA22013
BrawleyCALIFORNIA22010
Joshua Tree 2CALIFORNIA22013
OatmanARIZONA12025

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