BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Common Loon In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionWetland birds

Common Loon in Prairie Hardwood Transition has risen sharply: up 74% on the route-weighted index since 1968.

+74%Since 1968TrendPercent 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 →
38Routes 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 →
58YearsYears 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 →

Common Loon has risen sharply in Prairie Hardwood Transition: up 74% on the route-weighted index since 1968.

Common Loon In Prairie Hardwood Transition Population Forecast

If the recent trend holds, Common Loon in Prairie Hardwood Transition is projected to rise about 11% by 2029 — from 0.29 in 2024 to a central estimate of 0.33 (95% range 0.14–0.51). A 5-year backtest shows a typical error of ±74.1%, with 60% of held-out values landing inside the 95% band.

+11%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 →
0.33Projected 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 →
0.14–0.5195% 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 →
±74.1%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, Common Loon in Prairie Hardwood Transition is projected to rise about 11% by 2029 — from 0.29 in 2024 to a central estimate of 0.33 (95% range 0.14–0.51). A 5-year backtest shows a typical error of ±74.1%, with 60% of held-out values landing inside the 95% band.19662029
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 →
20250.320.130.50
20260.320.130.50
20270.320.140.51
20280.320.140.51
20290.330.140.51

Routes In Prairie Hardwood Transition

Routes recording Common Loon in Prairie Hardwood Transition.
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 →
EdwardsMINNESOTA102024
LoraineWISCONSIN52018
RemusMICHIGAN42024
Chippewa Lk.MICHIGAN42024
GlenwoodMINNESOTA32019
WeyerhauserWISCONSIN32024
CadottWISCONSIN32011
Oconto FallsWISCONSIN32023
OsseoMINNESOTA22019
EvergreenMINNESOTA22024
Brook ParkMINNESOTA22024
AshbyMINNESOTA22021
Sherburne NrMINNESOTA22024
HudsonWISCONSIN22024
DresserWISCONSIN22021
HatfieldWISCONSIN21995
MatherWISCONSIN22013
ElderonWISCONSIN22021
ScottvilleMICHIGAN12015
Big Blue LkMICHIGAN12011
Big RapidsMICHIGAN11972
NashvilleMICHIGAN11973
GalesburgMICHIGAN12015
HungerfordMICHIGAN12019
Belding 2MICHIGAN12010

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