BirdAnalyst
Species · BCR 15 · BBS 2025 Release · 1966–2024

Northern Rough-winged Swallow In Sierra Nevada

All regionsSierra NevadaAerial insectivores

Northern Rough-winged Swallow in Sierra Nevada has fallen sharply: down 75% on the route-weighted index since 1972.

-75%Since 1972
24Routes In Region
54Years

Notable Signals

long arc declinecomputed index

Northern Rough-winged Swallow has fallen sharply in Sierra Nevada: down 75% on the route-weighted index since 1972.

Forecast

If the recent trend holds, Northern Rough-winged Swallow in Sierra Nevada is projected to fall about 51% by 2029 — from 0.26 in 2024 to a central estimate of 0.13 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±94.6%, with 100% of held-out values landing inside the 95% band.

-51%Change by 2029
0.13Projected 2029 index
0.00–1.295% range
±94.6%Backtest error
19702029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20250.190.001.3
20260.180.001.2
20270.160.001.2
20280.150.001.2
20290.130.001.2

Routes In Sierra Nevada

Routes recording Northern Rough-winged Swallow in Sierra Nevada.
Bass LakeCALIFORNIA42007
GeneseeCALIFORNIA32024
CoultervilleCALIFORNIA32012
KernvilleCALIFORNIA32008
DardanelleCALIFORNIA21973
JohnsvilleCALIFORNIA22014
Silver CityCALIFORNIA21994
SattleyCALIFORNIA22012
Butte MeadowCALIFORNIA21997
PaxtonCALIFORNIA22024
Forest HillCALIFORNIA22019
Eagle LakeCALIFORNIA12013
Cottage SpgsCALIFORNIA11973
WoodfordsCALIFORNIA12009
Greenhorn MtCALIFORNIA11974
Kings CanyonCALIFORNIA12005
Tuolumne GroveCALIFORNIA12011
Higgins CornCALIFORNIA12013
DownievilleCALIFORNIA12019
RivertonCALIFORNIA12019
Hat CreekCALIFORNIA12015
LakeshoreCALIFORNIA11997
Little TruckeeCALIFORNIA12002
PlacervilleCALIFORNIA12011

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