BirdAnalyst
Species · BCR 23 · BBS 2025 Release · 1966–2024

Forster's Tern In Prairie Hardwood Transition

All regionsPrairie Hardwood TransitionWetland birds

Forster's Tern in Prairie Hardwood Transition has risen sharply: up 70% on the route-weighted index since 1975.

+70%Since 1975
16Routes In Region
48Years

Notable Signals

long arc increasecomputed index

Forster's Tern has risen sharply in Prairie Hardwood Transition: up 70% on the route-weighted index since 1975.

Forecast

If the recent trend holds, Forster's Tern in Prairie Hardwood Transition is projected to stay roughly flat through 2029, near 0.05 (95% range 0.00–0.21). A 5-year backtest shows a typical error of ±128.1%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2029
0.05Projected 2029 index
0.00–0.2195% range
±128.1%Backtest error
19722029
Projection of the recent trend (dashed) with 80/95% bands — a projection, not a prediction. Habitat, climate, and land use are not modeled.
YearProjected index95% low95% high
20250.060.000.22
20260.050.000.22
20270.050.000.22
20280.050.000.22
20290.050.000.21

Routes In Prairie Hardwood Transition

Routes recording Forster's Tern in Prairie Hardwood Transition.
Indiana DuneINDIANA121994
EdwardsMINNESOTA82022
Le CenterMINNESOTA52014
CascoWISCONSIN41989
JuniataMICHIGAN32004
OmroWISCONSIN32001
Rolling PrWISCONSIN32010
New LondonMINNESOTA22008
Sherburne NrMINNESOTA21997
HudsonWISCONSIN21986
BriggsvilleWISCONSIN22005
MinnetonkaMINNESOTA11995
ManawaWISCONSIN12001
PardeevilleWISCONSIN12024
BrownsvilleWISCONSIN12008
Omro 2WISCONSIN12022

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