BirdAnalyst
Species · BCR 5 · BBS 2025 Release · 1966–2024

Pied-billed Grebe In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestWetland birds

Pied-billed Grebe in Northern Pacific Rainforest has declined: down 44% on the route-weighted index since 1972.

-44%Since 1972TrendPercent 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 →
34Routes 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 →
52YearsYears 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 →

No notable trend signals for Pied-billed Grebe in Northern Pacific Rainforest. See the full index history below.

Pied-billed Grebe In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Pied-billed Grebe in Northern Pacific Rainforest is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±75.8%, with 80% of held-out values landing inside the 95% band.

n/aChange 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 →
0.04Projected 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 →
0.00–0.1295% 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 →
±75.8%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, Pied-billed Grebe in Northern Pacific Rainforest is projected to stay roughly flat through 2029, near 0.04 (95% range 0.00–0.12). A 5-year backtest shows a typical error of ±75.8%, with 80% 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 →
20250.040.000.12
20260.040.000.12
20270.040.000.12
20280.040.000.12
20290.040.000.12

Routes In Northern Pacific Rainforest

Routes recording Pied-billed Grebe in Northern Pacific Rainforest.
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 →
MontesandWASHINGTON51990
IssaquahWASHINGTON31976
CarnationWASHINGTON32018
HullvilleCALIFORNIA21996
UmpquaOREGON21979
Elk LakeOREGON22018
McminnvilleOREGON22017
SantiamOREGON22018
MendotaWASHINGTON21981
SitkaALASKA12010
Crescent CtyCALIFORNIA12024
MccloudCALIFORNIA11996
LaytonvilleCALIFORNIA12004
Bodega BayCALIFORNIA12006
YrekaCALIFORNIA12008
WinberryOREGON11994
WedderburnOREGON12023
AdairOREGON12012
DaytonOREGON11978
Nicolai Mtn.OREGON12008
Emigrant Lake 2OREGON12010
CanbyOREGON12017
Blue RiverOREGON12005
CoquilleOREGON11995
SalemOREGON12022

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