BirdAnalyst
Species · Nebraska · BBS 2025 Release · 1966–2024

Black Tern Population Trend in Nebraska

All statesWetland birds

Black Tern in Nebraska has collapsed: down 83% on the route-weighted index since 1969.

-83%Since 1969TrendPercent 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 →
16Routes In StateSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
49YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black Tern Trends in NebraskaNotable 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 →

Black Tern has collapsed in Nebraska: down 83% on the route-weighted index since 1969.

Black Tern Population Forecast in Nebraska

If the recent trend holds, Black Tern in Nebraska is projected to rise about 36% by 2029 — from 0.08 in 2024 to a central estimate of 0.11 (95% range 0.00–0.78). A 5-year backtest shows a typical error of ±40.5%, with 100% of held-out values landing inside the 95% band.

+36%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 →
0.11Projected 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 →
0.00–0.7895% 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 →
±40.5%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, Black Tern in Nebraska is projected to rise about 36% by 2029 — from 0.08 in 2024 to a central estimate of 0.11 (95% range 0.00–0.78). A 5-year backtest shows a typical error of ±40.5%, with 100% of held-out values landing inside the 95% band.19672029
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 →
20250.140.000.81
20260.130.000.80
20270.130.000.80
20280.120.000.79
20290.110.000.78

Black Tern Survey Routes in Nebraska

Routes recording Black Tern in Nebraska.
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 →
Swan Lake720221969
Gretna520151992
Piester Lake320181967
Kennedy320211993
Brownlee220181990
Nenzel220192019
Wheeler Co220241982
Table120032003
Kimball120052005
Gordon120242001
Crescent Lk120161980
Surprise119791975
Bassett120242019
Sparta119801967
Midway119801980
Johnstown119691969

Black Tern Population Trend in Other States

californiacoloradoidahoillinoisindianaiowakansasmainemichiganminnesotamissourimontananevadanew-yorknorth-dakotaohiooregonsouth-dakotatexasutahwashingtonwisconsinwyoming

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