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

Forster's Tern Population Trend in Nebraska

All statesWetland birds

Forster's Tern in Nebraska has edged down: down 13% on the route-weighted index since 1988.

-13%Since 1988TrendPercent 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 →
6Routes 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 →
31YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Forster's 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 →

No notable trend signals for Forster's Tern in Nebraska. See the full index history below.

Forster's Tern Population Forecast in Nebraska

If the recent trend holds, Forster's Tern in Nebraska is projected to stay roughly flat through 2024, near 0.22 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±579.7%, with 60% of held-out values landing inside the 95% band.

n/aChange by 2024TrendPercent 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 →
0.22Projected 2024 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.4795% 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 →
±579.7%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, Forster's Tern in Nebraska is projected to stay roughly flat through 2024, near 0.22 (95% range 0.00–0.47). A 5-year backtest shows a typical error of ±579.7%, with 60% of held-out values landing inside the 95% band.19812024
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 →
20200.210.000.46
20210.210.000.46
20220.210.000.46
20230.220.000.47
20240.220.000.47

Forster's Tern Survey Routes in Nebraska

Routes recording Forster's 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 →
Murray Lake220092009
Gordon120052005
Crescent Lk120161981
Brownlee120082008
Piester Lake120191992
Kennedy120141995

Forster's Tern Population Trend in Other States

alabamacaliforniacoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaslouisianamarylandmichiganminnesotamontananevadanew-jerseynew-yorknorth-carolinanorth-dakotaoregonsouth-carolinasouth-dakotatexasutahvirginiawashingtonwisconsinwyoming

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