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

Caspian Tern Population Trend in Minnesota

All statesWetland birds

Caspian Tern in Minnesota has held roughly steady: down 9% on the route-weighted index since 1985.

-9%Since 1985TrendPercent 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 →
14Routes 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 →
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 Caspian Tern Trends in MinnesotaNotable 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 Caspian Tern in Minnesota. See the full index history below.

Caspian Tern Survey Routes in Minnesota

Routes recording Caspian Tern in Minnesota.
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 →
Pine River719861986
Backus619921989
Hartland319901990
Edwards319871983
Big Stone219971997
Le Center220112011
Minnetonka119961992
Nebish119891989
Princeton120012001
Osseo119921992
Knapp119921992
St Stephen119931993
Mille Lacs119791979
Evergreen119901985

Caspian Tern Population Trend in Other States

alabamaalaskacaliforniadelawarefloridaidahoillinoisindianalouisianamarylandmichiganmontananevadanorth-carolinanorth-dakotaoregonsouth-carolinatexasutahvermontvirginiawashingtonwisconsinwyoming

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