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

Least Tern Population Trend in Arkansas

All statesWetland birds

Least Tern in Arkansas has declined: down 27% on the route-weighted index since 1989.

-27%Since 1989TrendPercent 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 →
7Routes 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 →
23YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Least Tern Trends in ArkansasNotable 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 Least Tern in Arkansas. See the full index history below.

Least Tern Population Forecast in Arkansas

If the recent trend holds, Least Tern in Arkansas is projected to fall about 79% by 2029 — from 0.32 in 2024 to a central estimate of 0.07 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±64.5%, with 80% of held-out values landing inside the 95% band.

-79%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 →
0.07Projected 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 →
0.00–0.2495% 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 →
±64.5%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, Least Tern in Arkansas is projected to fall about 79% by 2029 — from 0.32 in 2024 to a central estimate of 0.07 (95% range 0.00–0.24). A 5-year backtest shows a typical error of ±64.5%, with 80% of held-out values landing inside the 95% band.19812029
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 →
20250.070.000.24
20260.070.000.24
20270.070.000.24
20280.070.000.24
20290.070.000.24

Least Tern Survey Routes in Arkansas

Routes recording Least Tern in Arkansas.
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 →
Wilson920242013
Gillett220142011
Coal Hill220192007
Eudora120091995
Hughes120211981
Crowley'S Ridge120222022
South Bend120121996

Least Tern Population Trend in Other States

alabamacaliforniacoloradodelawarefloridageorgiaillinoiskansaskentuckylouisianamainemarylandmassachusettsmississippimissourinebraskanew-jerseynew-yorknorth-carolinaoklahomasouth-carolinatennesseetexasvirginia

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