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

Red-breasted Merganser In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestWaterfowl

Red-breasted Merganser in Northern Pacific Rainforest has fallen sharply: down 53% on the route-weighted index since 1991.

-53%Since 1991TrendPercent 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 →
9Routes 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 →
15YearsYears 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 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 →

Red-breasted Merganser has fallen sharply in Northern Pacific Rainforest: down 53% on the route-weighted index since 1991.

Routes In Northern Pacific Rainforest

Routes recording Red-breasted Merganser 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 →
HainesALASKA62008
KetchikanALASKA22009
CordovaALASKA21996
Thompson PasALASKA22002
Harlequin L.ALASKA22005
HyderALASKA21995
SewardALASKA11983
Thorne BayALASKA12012
Mitkof IsleALASKA12013

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