Species · Wisconsin · BBS 2025 Release · 1966–2024

Mourning Warbler Population Trend in Wisconsin

Mourning Warbler in Wisconsin has increased: up 35% on the route-weighted index since 1968.

+35%Since 1968
80Routes In State
58Years

Notable Mourning Warbler Trends in Wisconsin

No notable trend signals for Mourning Warbler in Wisconsin. See the full index history below.

Mourning Warbler Population Forecast in Wisconsin

If the recent trend holds, Mourning Warbler in Wisconsin is projected to rise about 49% by 2029 — from 2.0 in 2024 to a central estimate of 3.0 (95% range 1.2–4.7). A 5-year backtest shows a typical error of ±62.4%, with 100% of held-out values landing inside the 95% band.

+49%Change by 2029
3.0Projected 2029 index
1.24.795% range
±62.4%Backtest error
19662029
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
20252.91.24.7
20262.91.24.7
20272.91.24.7
20283.01.24.7
20293.01.24.7

Mourning Warbler Survey Routes in Wisconsin

Routes recording Mourning Warbler in Wisconsin.
Bayfield1520241967
Mellen1520241998
Montreal1320241968
Popple River1220241966
Cavour1020241998
Amnicon Falls920241998
Hollister820241967
Shanagolden720241966
Iron River620241967
Grand View620241966
Land O Lakes620161967
Amberg620241980
Land O' Lakes 2620242017
Chaffey520241966
Couderay520191969
Irma520241967
Mcnaughton520241967
Flambeau420241998
Minong320241967
Cumberland320181966
Cadott320191968
Hatfield319791978
Wis Rapids320151981
Stevens Pt320231980
Holway219891967

Mourning Warbler Population Trend in Other States

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