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

Northern Mockingbird Population Trend in Connecticut

All statesGeneralists

Northern Mockingbird in Connecticut has surged: up 290% on the route-weighted index since 1970.

+290%Since 1970TrendPercent 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 →
19Routes 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 Northern Mockingbird Trends in ConnecticutNotable 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 Mockingbird has surged in Connecticut: up 290% on the route-weighted index since 1970.

Northern Mockingbird Population Forecast in Connecticut

If the recent trend holds, Northern Mockingbird in Connecticut is projected to rise about 68% by 2029 — from 1.0 in 2024 to a central estimate of 1.7 (95% range 0.00–9.6). A 5-year backtest shows a typical error of ±161.4%, with 100% of held-out values landing inside the 95% band.

+68%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 →
1.7Projected 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 →
0.00–9.695% 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 →
±161.4%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 Mockingbird in Connecticut is projected to rise about 68% by 2029 — from 1.0 in 2024 to a central estimate of 1.7 (95% range 0.00–9.6). A 5-year backtest shows a typical error of ±161.4%, with 100% of held-out values landing inside the 95% band.19682029
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 →
20252.10.0010
20262.00.009.9
20271.90.009.8
20281.80.009.7
20291.70.009.6

Northern Mockingbird Survey Routes in Connecticut

Routes recording Northern Mockingbird in Connecticut.
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 →
New Hartford919871972
E Hartland619921969
Mystic320231973
Uncasville320241973
Woodstock220051973
Sherman220181972
Long Hill220181972
Granby220241988
Buckingham120221970
Westbrook120241969
Willimantic120181971
No Woodbury120241970
Greenwich120171968
Danbury120231971
Warren120101974
Mid Haddam120241973
Southington120241973
New Hartford120061994
Warren 2120162016

Northern Mockingbird Population Trend in Other States

alabamaarizonaarkansascaliforniacoloradodelawarefloridageorgiaidahoillinoisindianaiowakansaskentuckylouisianamainemarylandmassachusettsmichiganminnesotamississippimissourimontananebraskanevadanew-hampshirenew-jerseynew-mexiconew-yorknorth-carolinanorth-dakotaohiooklahomaoregonpennsylvaniarhode-islandsouth-carolinasouth-dakotatennesseetexasutahvermontvirginiawashingtonwest-virginiawisconsinwyoming

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