BirdAnalyst
Species · BCR 26 · BBS 2026 Release · 1966–2025

Northern Rough-winged Swallow In Mississippi Alluvial Valley

All regionsMississippi Alluvial ValleyAerial insectivores

Northern Rough-winged Swallow in Mississippi Alluvial Valley has surged: up 19× on the route-weighted index since 1969.

19×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 →
58Routes In RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
58YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable SignalsNotable 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 →

Northern Rough-winged Swallow has surged in Mississippi Alluvial Valley: up 19× on the route-weighted index since 1969.

Northern Rough-winged Swallow In Mississippi Alluvial Valley Population Forecast

If the recent trend holds, Northern Rough-winged Swallow in Mississippi Alluvial Valley is projected to fall about 43% by 2030 — from 12 in 2025 to a central estimate of 6.7 (95% range 0.00–14). A 5-year backtest shows a typical error of ±56.3%, with 40% of held-out values landing inside the 95% band.

-43%Change by 2030TrendPercent 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 →
6.7Projected 2030 indexProjected indexThe central forecast of the abundance index if the recent trend continues. A projection of the current trajectory, not a prediction.Full methodology →
0.00–1495% 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 →
±56.3%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, Northern Rough-winged Swallow in Mississippi Alluvial Valley is projected to fall about 43% by 2030 — from 12 in 2025 to a central estimate of 6.7 (95% range 0.00–14). A 5-year backtest shows a typical error of ±56.3%, with 40% of held-out values landing inside the 95% band.19672030
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 →
20266.40.0013
20276.50.0013
20286.50.0013
20296.60.0013
20306.70.0014

Routes In Mississippi Alluvial Valley

Routes recording Northern Rough-winged Swallow in Mississippi Alluvial Valley.
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 →
WilsonARKANSAS3872025
DeventerMISSOURI2222024
Delta N.F.MISSISSIPPI1152016
Eagle LakeMISSISSIPPI1102023
Tchula 3MISSISSIPPI642022
ShawLOUISIANA382024
IsolaMISSISSIPPI332022
KeystoneLOUISIANA312004
EnglandARKANSAS122025
PawpawTENNESSEE112009
FrogmoreLOUISIANA102024
TransylvaniaLOUISIANA102022
DundeeMISSISSIPPI102022
Bardwell 2KENTUCKY72025
MayflowerLOUISIANA72024
Morgan CityLOUISIANA62018
Cp GirardeauMISSOURI62018
South BendARKANSAS52023
MaynardARKANSAS52025
Port AllenLOUISIANA52022
HughesARKANSAS42025
SaffellARKANSAS42019
Augusta 2ARKANSAS42009
MoonMISSISSIPPI42019
HarrisburgARKANSAS31987

Source: USGS North American Breeding Bird Survey, retrieved 2026-08-14.