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

Bonaparte's Gull In Northern Pacific Rainforest

All regionsNorthern Pacific RainforestWetland birds

Bonaparte's Gull in Northern Pacific Rainforest has surged: up 619% on the route-weighted index since 1984.

+619%Since 1984TrendPercent 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 →
18Routes 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 →
33YearsYears 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 →

Bonaparte's Gull has surged in Northern Pacific Rainforest: up 619% on the route-weighted index since 1984.

Bonaparte's Gull In Northern Pacific Rainforest Population Forecast

If the recent trend holds, Bonaparte's Gull in Northern Pacific Rainforest is projected to stay roughly flat through 2023, near 0.00 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±247.5%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2023TrendPercent 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 →
0.00Projected 2023 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–2.595% 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 →
±247.5%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, Bonaparte's Gull in Northern Pacific Rainforest is projected to stay roughly flat through 2023, near 0.00 (95% range 0.00–2.5). A 5-year backtest shows a typical error of ±247.5%, with 100% of held-out values landing inside the 95% band.19712023
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 →
20190.000.002.5
20200.000.002.5
20210.000.002.5
20220.000.002.5
20230.000.002.5

Routes In Northern Pacific Rainforest

Routes recording Bonaparte's Gull 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 →
Juneau AltALASKA3351985
KetchikanALASKA552017
PetersburgALASKA241987
ZaremboALASKA202001
Zimovia StrtALASKA42017
Warm BeachWASHINGTON41986
YakutatALASKA32018
Mitkof IsleALASKA32010
HainesALASKA21997
Sheep MtnALASKA22017
SkagwayALASKA22011
Kuiu IslandALASKA22010
HoneydewCALIFORNIA21973
WedderburnOREGON21985
Elmendorf (Short)ALASKA11984
Sitka (Short)ALASKA11986
HullvilleCALIFORNIA11971
Port AngelesWASHINGTON12012

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