BirdAnalyst
Species · BCR 27 · BBS 2025 Release · 1966–2024

Common Tern In Southeastern Coastal Plain

All regionsSoutheastern Coastal PlainWetland birds

Common Tern in Southeastern Coastal Plain has held roughly steady: up 5% on the route-weighted index since 1969.

+5%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 →
9Routes 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 →
29YearsYears 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 →

No notable trend signals for Common Tern in Southeastern Coastal Plain. See the full index history below.

Forecast

If the recent trend holds, Common Tern in Southeastern Coastal Plain is projected to stay roughly flat through 2019, near 0.00 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±324.4%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2019TrendPercent 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 →
0.00Projected 2019 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.0995% 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 →
±324.4%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 Tern in Southeastern Coastal Plain is projected to stay roughly flat through 2019, near 0.00 (95% range 0.00–0.09). A 5-year backtest shows a typical error of ±324.4%, with 100% of held-out values landing inside the 95% band.19662019
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 →
20150.000.000.09
20160.000.000.09
20170.000.000.09
20180.000.000.09
20190.000.000.09

Routes In Southeastern Coastal Plain

Routes recording Common Tern in Southeastern Coastal Plain.
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 →
Dauphin Is 2ALABAMA32014
St Vincent IFLORIDA22010
Myrtle GroveNORTH-CAROLINA22014
MashoesNORTH-CAROLINA21973
Dauphin IsALABAMA11989
Ft Waltn BchFLORIDA11976
ShallotteNORTH-CAROLINA11981
MerrimonNORTH-CAROLINA12003
GrandyNORTH-CAROLINA11975

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