Species · BBS 2025 Release · 1966–2024

Brown Creeper

CerthiidaeForest birdsCerthia americana

Brown Creeper has surged: up 553% on the route-weighted index since 1968.

About the Brown Creeper

The Brown Creeper (Certhia americana) is a North American member of the Treecreepers (Certhiidae). In this analysis it is grouped with the forest birds.

Size
4.5–5.5 in long (12–14 cm) — a tiny tree-climbing bird (typical for the family)
Habitat
Woodlands and forest edges, including wooded suburbs and parks.
Diet
Insects and spiders gleaned from foliage and bark, with seeds and berries in season.
Range
Recorded on 1,023 Breeding Bird Survey routes across 37 states, most concentrated in the Northern Pacific Rainforest.
Family
Certhiidae · Forest birds

Notable Brown Creeper 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 Brown Creeper. See the full index history below.

Brown Creeper Population Forecast

If the recent trend holds, Brown Creeper is projected to stay roughly flat through 2029, near 0.27 (95% range 0.21–0.33). A 5-year backtest shows a typical error of ±19.7%, with 60% of held-out values landing inside the 95% band.

If the recent trend holds, Brown Creeper is projected to stay roughly flat through 2029, near 0.27 (95% range 0.21–0.33). A 5-year backtest shows a typical error of ±19.7%, with 60% 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 →
20250.260.200.32
20260.270.210.33
20270.270.210.33
20280.270.210.33
20290.270.210.33

Where the Brown Creeper Is Detected

BBS routes recording Brown Creeper, sized by most recent count.

Brown Creeper Population Trend by State

Brown Creeper 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 →
Alaska-61%198245
Arizona+130%197620
California+308%1970129
Colorado-29%197539
Connecticut+21%197119
Idaho-46%197429
Illinoisinsufficient datan/a1
Indianainsufficient datan/a1
Iowainsufficient datan/a1
Maine+120%196863
Maryland+78%19789
Massachusetts+462%196831
Michigan+408%197563
Minnesota+704%197825
Montana+36%197923
Nebraskainsufficient datan/a1
Nevadainsufficient datan/a4
New Hampshire+757%196825
New Jersey-0%19827
New Mexico-45%198116
New York+200%196888
North Carolina+13%19938
North Dakotainsufficient datan/a1
Ohio+57%20016
Oregon+30%197095
Pennsylvania+682%197068
Rhode Islandinsufficient datan/a5
South Dakota+54%199810
Tennessee+217%19913
Texasinsufficient datan/a1
Utah-50%199018
Vermont+590%196922
Virginia+3%199410
Washington+402%197168
West Virginia+754%198016
Wisconsin+180%196939
Wyoming-34%199114

Brown Creeper Population Trend by Region

Bird Conservation Regions are the ecological unit for trends.

Brown Creeper 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 →
BCR 2-68%19904
BCR 4-67%198516
Northern Pacific Rainforest+286%1970148
Great Basin+16%197064
Northern Rockies+13%197093
Boreal Hardwood Transition+418%196998
Lower Great Lakes / St. Lawrence Plain+348%196845
Atlantic Northern Forest+381%1968137
Sierra Nevada+137%197039
Southern Rockies / Colorado Plateau+197%197474
Badlands and Prairies+46%199810
Prairie Hardwood Transition+162%197829
Appalachian Mountains15×1968138
New England / Mid-Atlantic Coast+371%196857
Coastal California+21%197139
Sierra Madre Occidental+6%197619

Brown Creeper Conservation Status

Our route-weighted index shows it up about 553% since 1968.

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