BirdAnalyst
Species · BCR 14 · BBS 2025 Release · 1966–2024

Common Tern In Atlantic Northern Forest

All regionsAtlantic Northern ForestWetland birds

Common Tern in Atlantic Northern Forest has surged: up 304% on the route-weighted index since 1984.

+304%Since 1984TrendPercent 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 →
5Routes 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 →
13YearsYears 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 Tern has surged in Atlantic Northern Forest: up 304% on the route-weighted index since 1984.

Routes In Atlantic Northern Forest

Routes recording Common Tern in Atlantic Northern Forest.
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 →
St DavidMAINE112005
DebloisMAINE41966
Baker LakeMAINE31997
NewcastleMAINE11973
MedwayMAINE11993

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