BirdAnalyst
Species · BBS 2025 Release · 1966–2024

Western Kingbird

TyrannidaeAerial insectivoresTyrannus verticalis

Western Kingbird has increased: up 49% on the route-weighted index since 1969.

+49%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 →
1,607RoutesSurvey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
57Years SurveyedYears surveyedNumber of years with at least one standard-protocol run in this geography. A longer record makes the trend more reliable.Full methodology →

About the Western Kingbird

The Western Kingbird (Tyrannus verticalis) is a North American member of the Tyrant Flycatchers (Tyrannidae). In this analysis it is grouped with the aerial insectivores.

Size
4.5–9 in long (12–23 cm) — a small to medium flycatcher (typical for the family)
Habitat
Open airspace over fields, water and towns; nests in cavities, earthen banks or on structures.
Diet
Flying insects caught on the wing.
Range
Recorded on 1,607 Breeding Bird Survey routes across 29 states, most concentrated in the Great Basin.
Family
Tyrannidae · Aerial insectivores

Notable Western Kingbird TrendsNotable signalsLong-arc shifts the engine flags automatically — sustained declines or increases large enough to stand out from year-to-year noise.Full methodology →

No notable trend signals for Western Kingbird. See the full index history below.

Western Kingbird Population Forecast

If the recent trend holds, Western Kingbird is projected to rise about 38% by 2029 — from 2.3 in 2024 to a central estimate of 3.2 (95% range 2.3–4.1). A 5-year backtest shows a typical error of ±50%, with 0% of held-out values landing inside the 95% band.

+38%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 →
3.2Projected 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 →
2.3–4.195% 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 →
±50%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, Western Kingbird is projected to rise about 38% by 2029 — from 2.3 in 2024 to a central estimate of 3.2 (95% range 2.3–4.1). A 5-year backtest shows a typical error of ±50%, with 0% of held-out values landing inside the 95% band.19672029
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 →
20253.22.34.1
20263.22.34.1
20273.22.34.1
20283.22.34.1
20293.22.34.1

Where the Western Kingbird Is Detected

BBS routes recording Western Kingbird, sized by most recent count.

Western Kingbird Population Trend by State

Western Kingbird population trend by state.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Alaskainsufficient datan/a1
Arizona-74%197081
Arkansas+95%20025
California+7%1970219
Colorado-7%1970125
Idaho+157%197046
Illinoisinsufficient datan/a4
Indianainsufficient datan/a1
Iowa-72%196914
Kansas-71%196964
Louisianainsufficient datan/a1
Michiganinsufficient datan/a1
Minnesota-63%196934
Mississippiinsufficient datan/a1
Missouri-80%197121
Montana+74%197081
Nebraska+10%196971
Nevada+54%197248
New Mexico+61%197283
North Dakota+55%196950
Oklahoma-35%196962
Oregon-0%197087
South Dakota-71%196959
Tennesseeinsufficient datan/a1
Texas+824%1969205
Utah+228%197091
Washington-20%197066
Wisconsininsufficient datan/a3
Wyoming+142%197082

Western Kingbird Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Western Kingbird population trend by Bird Conservation Region.
TrendPercent 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 →Baseline yearThe first year of the smoothed window the trend is measured from. An earlier baseline means a longer record stands behind the number.Full methodology →Survey routesHow many standard-protocol BBS routes contributed counts. More routes means a steadier, better-sampled index; very thin coverage is suppressed.Full methodology →
Northern Pacific Rainforest-42%197052
Great Basin+30%1970226
Northern Rockies+238%1970114
Prairie Potholes-35%1969106
Sierra Nevada+27%197220
Southern Rockies / Colorado Plateau-19%1970181
Badlands and Prairies+16%1969126
Shortgrass Prairie+181%1969137
Central Mixed Grass Prairie-65%1969129
Edwards Plateau+326%197319
Oaks and Prairies+615%196972
Eastern Tallgrass Prairie-65%196969
Prairie Hardwood Transition-48%197011
Central Hardwoods+2%20068
West Gulf Coastal Plain / Ouachitas-41%197815
Coastal California+25%1970108
Sonoran and Mojave Deserts-59%197083
Sierra Madre Occidental-82%197032
Chihuahuan Desert+607%196954
Tamaulipan Brushlands24×197125
Gulf Coastal Prairie+45%198413

Western Kingbird Conservation Status

Our route-weighted index shows it up about 49% since 1969. Aerial insectivores have fallen sharply across the continent, a decline widely linked to dwindling insect prey.

Source: USGS North American Breeding Bird Survey, retrieved 2026-05-22. Trend is a route-weighted relative-abundance index, not an absolute population.