BirdAnalyst
Species · BCR 24 · BBS 2025 Release · 1966–2024

Double-crested Cormorant In Central Hardwoods

All regionsCentral HardwoodsWetland birds

Double-crested Cormorant in Central Hardwoods has surged: up 45× on the route-weighted index since 1996.

45×Since 1996TrendPercent 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 RegionSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
27YearsYears 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 →

Double-crested Cormorant has surged in Central Hardwoods: up 45× on the route-weighted index since 1996.

Double-crested Cormorant In Central Hardwoods Population Forecast

If the recent trend holds, Double-crested Cormorant in Central Hardwoods is projected to rise about 457% by 2029 — from 0.11 in 2024 to a central estimate of 0.60 (95% range 0.00–1.4). A 5-year backtest shows a typical error of ±1377.5%, with 100% of held-out values landing inside the 95% band.

+457%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 →
0.60Projected 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 →
0.00–1.495% 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 →
±1377.5%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, Double-crested Cormorant in Central Hardwoods is projected to rise about 457% by 2029 — from 0.11 in 2024 to a central estimate of 0.60 (95% range 0.00–1.4). A 5-year backtest shows a typical error of ±1377.5%, with 100% of held-out values landing inside the 95% band.19912029
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 →
20250.520.001.4
20260.540.001.4
20270.560.001.4
20280.580.001.4
20290.600.001.4

Routes In Central Hardwoods

Routes recording Double-crested Cormorant in Central Hardwoods.
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 →
Wheeler DamALABAMA1022023
ElkmontALABAMA362014
KarnakILLINOIS242013
PleasurevillKENTUCKY112015
SanduskyILLINOIS72016
PeytonsvilleTENNESSEE72024
Valhermoso SpgsALABAMA32010
BelmontINDIANA32003
TrianaALABAMA22011
DelwoodILLINOIS22024
RoyaltonILLINOIS22002
TullahomaTENNESSEE22015
Valhermoso Spg 2ALABAMA12014
RussellARKANSAS12017
Brnt PrairieILLINOIS12016
PulaskiILLINOIS12024
BelknapILLINOIS12022
Beaverdam LkILLINOIS12023
PimentoINDIANA12021
CantonKENTUCKY12015
KeysburgKENTUCKY12012
RiverqueenKENTUCKY12018
PulaskiMISSOURI12022
CentertownMISSOURI11994
Pond CreekTENNESSEE12001

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