BirdAnalyst
Species · BCR 9 · BBS 2025 Release · 1966–2024

Tricolored Blackbird In Great Basin

All regionsGreat BasinGeneralists

Tricolored Blackbird in Great Basin has collapsed: down 86% on the route-weighted index since 1972.

-86%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 →
14Routes 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 →
40YearsYears 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 →

Tricolored Blackbird has collapsed in Great Basin: down 86% on the route-weighted index since 1972.

Tricolored Blackbird In Great Basin Population Forecast

If the recent trend holds, Tricolored Blackbird in Great Basin is projected to stay roughly flat through 2029, near 0.53 (95% range 0.00–2.7). A 5-year backtest shows a typical error of ±4987.9%, with 100% 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 →
0.53Projected 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 →
0.00–2.795% 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 →
±4987.9%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, Tricolored Blackbird in Great Basin is projected to stay roughly flat through 2029, near 0.53 (95% range 0.00–2.7). A 5-year backtest shows a typical error of ±4987.9%, with 100% of held-out values landing inside the 95% band.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 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 →
20250.550.002.8
20260.540.002.8
20270.540.002.8
20280.530.002.7
20290.530.002.7

Routes In Great Basin

Routes recording Tricolored Blackbird in Great Basin.
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 →
DorrisCALIFORNIA2152007
Iron GateCALIFORNIA452011
MacdoelCALIFORNIA321987
IngallsCALIFORNIA211998
MerrillOREGON202012
Modoc PointOREGON101992
Honey LakeCALIFORNIA62017
NubieberCALIFORNIA42006
ChinchaloOREGON22013
LikelyCALIFORNIA12024
Crowder FlatCALIFORNIA12007
Lone RockOREGON11999
Bly 2OREGON12014
Scootney ReservoirWASHINGTON12024

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