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

Field Sparrow Population Trend in Louisiana

All statesGeneralists

Field Sparrow in Louisiana has collapsed: down 91% on the route-weighted index since 1969.

-91%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 →
27Routes 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 →
44YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Field Sparrow 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 declinecomputed 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 →

Field Sparrow has collapsed in Louisiana: down 91% on the route-weighted index since 1969.

Field Sparrow Population Forecast in Louisiana

If the recent trend holds, Field Sparrow in Louisiana is projected to stay roughly flat through 2020, near 0.00 (95% range 0.00–0.91). A 5-year backtest shows a typical error of ±155.7%, with 100% of held-out values landing inside the 95% band.

n/aChange by 2020TrendPercent 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 →
0.00Projected 2020 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–0.9195% 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 →
±155.7%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, Field Sparrow in Louisiana is projected to stay roughly flat through 2020, near 0.00 (95% range 0.00–0.91). A 5-year backtest shows a typical error of ±155.7%, with 100% of held-out values landing inside the 95% band.19672020
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 →
20160.000.000.91
20170.000.000.91
20180.000.000.91
20190.000.000.91
20200.000.000.91

Field Sparrow Survey Routes in Louisiana

Routes recording Field Sparrow 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 →
Derry719891970
Freetown419781978
Roseland419711971
Mamou319711971
Longstreet320091967
Many319911991
Womack320071999
Derry 2320001990
Easton219751975
Fort Polk219751967
Rayville219731971
Gran Chenier119811981
Lacombe119681968
Plettenberg119901973
De Ridder120141967
Mayflower119711971
Cypress119731970
Chatham119721971
Clay120101971
Fillmore119781969
Lake Cove120152014
Trout120001997
Carterville119921992
De Quincy120152015
Zwolle119981998

Field Sparrow Population Trend in Other States

alabamaarkansascoloradoconnecticutdelawarefloridageorgiaillinoisindianaiowakansaskentuckymainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanew-hampshirenew-jerseynew-yorknorth-carolinanorth-dakotaohiooklahomapennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasvermontvirginiawest-virginiawisconsinwyoming

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