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Species · Louisiana · BBS 2025 Release · 1966–2024

Black-and-white Warbler Population Trend in Louisiana

All statesForest birds

Black-and-white Warbler in Louisiana has risen sharply: up 52% on the route-weighted index since 1969.

+52%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 →
36Routes 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 →
56YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Black-and-white Warbler Trends in LouisianaNotable 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 →

Black-and-white Warbler has risen sharply in Louisiana: up 52% on the route-weighted index since 1969.

Black-and-white Warbler Population Forecast in Louisiana

If the recent trend holds, Black-and-white Warbler in Louisiana is projected to fall about 52% by 2029 — from 0.61 in 2024 to a central estimate of 0.29 (95% range 0.00–0.75). A 5-year backtest shows a typical error of ±57.5%, with 60% of held-out values landing inside the 95% band.

-52%Change by 2029TrendPercent 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 →
0.29Projected 2029 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.7595% 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 →
±57.5%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, Black-and-white Warbler in Louisiana is projected to fall about 52% by 2029 — from 0.61 in 2024 to a central estimate of 0.29 (95% range 0.00–0.75). A 5-year backtest shows a typical error of ±57.5%, with 60% of held-out values landing inside the 95% band.19672029
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 →
20250.300.000.76
20260.300.000.76
20270.290.000.76
20280.290.000.75
20290.290.000.75

Black-and-white Warbler Survey Routes in Louisiana

Routes recording Black-and-white Warbler in Louisiana.
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 →
Carterville1319921992
Chatham619731967
Marion619951988
Evelyn620242009
Womack520241999
Linville420241998
Clay320231973
Ivan 2320162014
Plettenberg220021973
Ivan220121998
Trout220231994
Goodwill220242004
Enterprise220242008
Haughton120221990
Fort Jessup120221998
Easton119821968
Derry119881969
Fishville120111970
Cypress119811970
Fort Polk119711971
Longstreet120241967
Fillmore119861970
Lake Cove120152013
Greensburg119991999
Many119891989

Black-and-white Warbler Population Trend in Other States

alabamaarkansascaliforniaconnecticutdelawaregeorgiaillinoisindianakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourinebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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