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

Tree Swallow Population Trend in Maine

All statesAerial insectivores

Tree Swallow in Maine has collapsed: down 87% on the route-weighted index since 1968.

-87%Since 1968
77Routes In State
58Years

Notable Tree Swallow Trends in Maine

long arc declinecomputed index

Tree Swallow has collapsed in Maine: down 87% on the route-weighted index since 1968.

Tree Swallow Population Forecast in Maine

If the recent trend holds, Tree Swallow in Maine is projected to fall about 100% by 2029 — from 1.9 in 2024 to a central estimate of 0.00 (95% range 0.00–7.0). A 5-year backtest shows a typical error of ±75.6%, with 100% of held-out values landing inside the 95% band.

-100%Change by 2029
0.00Projected 2029 index
0.00–7.095% range
±75.6%Backtest error
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 index95% low95% high
20250.250.007.3
20260.000.007.0
20270.000.007.0
20280.000.007.0
20290.000.007.0

Tree Swallow Survey Routes in Maine

Routes recording Tree Swallow in Maine.
Northfield4519811976
Benton4419801971
Manchester3919951971
Waite2419771977
Medway2020181976
Moose River1820081983
St David1420051982
Forest Sta1320001966
Carrabassett1220231983
Boundary1220161993
Otisfield Gr1120151966
Warren1119901973
Carrying Pl1020231979
Charleston1020191975
Brooks920191977
Jefferson920101991
Turner820101972
Hermon720191966
Seboomook Lk720141972
Grnd Lk Strm720001966
Rome720231996
Harmony620241967
Baxter619841977
Cambridge620141967
Washburn620051979

Tree Swallow Population Trend in Other States

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

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