BirdAnalyst
Species · BCR 10 · BBS 2025 Release · 1966–2024

Pacific Wren In Northern Rockies

All regionsNorthern RockiesForest birds

Pacific Wren in Northern Rockies has surged: up 606% on the route-weighted index since 1970.

+606%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 →
73Routes 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 →
54YearsYears 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 →

Pacific Wren has surged in Northern Rockies: up 606% on the route-weighted index since 1970.

Forecast

If the recent trend holds, Pacific Wren in Northern Rockies is projected to rise about 268% by 2029 — from 0.41 in 2024 to a central estimate of 1.5 (95% range 0.74–2.3). A 5-year backtest shows a typical error of ±155.6%, with 20% of held-out values landing inside the 95% band.

+268%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 →
1.5Projected 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 →
0.74–2.395% 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 →
±155.6%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, Pacific Wren in Northern Rockies is projected to rise about 268% by 2029 — from 0.41 in 2024 to a central estimate of 1.5 (95% range 0.74–2.3). A 5-year backtest shows a typical error of ±155.6%, with 20% of held-out values landing inside the 95% band.19682029
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 →
20251.40.652.2
20261.40.682.2
20271.50.702.2
20281.50.722.3
20291.50.742.3

Routes In Northern Rockies

Routes recording Pacific Wren in Northern Rockies.
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 →
Lolo PassIDAHO152019
SkalkahoMONTANA121998
Whitefish LakeMONTANA122024
Sullivan LkWASHINGTON121999
PierceIDAHO112007
NezperceIDAHO102012
MivodenIDAHO82023
AveryIDAHO82023
GoldenIDAHO82015
CusickWASHINGTON82022
Sullivan Lake 2WASHINGTON82024
Marble CreekIDAHO62023
Salmon RiverIDAHO62021
N Fork Cda RIDAHO62019
Swan LakeMONTANA62024
L Pend O NwrWASHINGTON62024
Baldy MountainIDAHO42015
Nezperce NfIDAHO41999
Libby DamMONTANA42000
St RegisMONTANA32024
ArleeMONTANA32024
NinemileMONTANA32022
Skalkho-RyeMONTANA32022
Threemile WaMONTANA32024
TroyOREGON32023

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