BirdAnalyst
Species · New Jersey · BBS 2025 Release · 1966–2024

Great Blue Heron Population Trend in New Jersey

All statesWetland birds

Great Blue Heron in New Jersey has surged: up 401% on the route-weighted index since 1968.

+401%Since 1968TrendPercent 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 →
35Routes 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 →
57YearsYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

Notable Great Blue Heron Trends in New JerseyNotable 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 →

Great Blue Heron has surged in New Jersey: up 401% on the route-weighted index since 1968.

Great Blue Heron Population Forecast in New Jersey

If the recent trend holds, Great Blue Heron in New Jersey is projected to rise about 31% by 2029 — from 0.76 in 2024 to a central estimate of 1.00 (95% range 0.13–1.9). A 5-year backtest shows a typical error of ±34.8%, with 100% of held-out values landing inside the 95% band.

+31%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 →
1.00Projected 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 →
0.13–1.995% 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 →
±34.8%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, Great Blue Heron in New Jersey is projected to rise about 31% by 2029 — from 0.76 in 2024 to a central estimate of 1.00 (95% range 0.13–1.9). A 5-year backtest shows a typical error of ±34.8%, with 100% of held-out values landing inside the 95% band.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 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 →
20250.960.091.8
20260.970.101.8
20270.980.101.9
20280.990.121.9
20291.000.131.9

Great Blue Heron Survey Routes in New Jersey

Routes recording Great Blue Heron in New Jersey.
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 →
Croton420021970
Hope419931970
Pottersville320231977
Ramseysburg320241995
Woodbury Hgt220231967
Albion219921992
Bloomsbury220241973
Dover220231992
Pomona220211979
Ocean City220241984
Pedricktown 2220242014
Pedricktown220121992
Winslow220231990
Greenwich120241966
Six Points120211979
Spraguetown 2120052005
Toms River120241968
Ancora119731973
Bennett Mill119991996
Sandbrook120181988
Holmansville120042004
Clarksville119781978
New Bedford120141988
Midvale120221970
Kemah Lake120221968

Great Blue Heron Population Trend in Other States

alabamaalaskaarizonaarkansascaliforniacoloradoconnecticutdelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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