Bank Swallow
Bank Swallow has fallen sharply: down 74% on the route-weighted index since 1968.
About the Bank Swallow
The smallest North American swallow, the Bank Swallow digs nest burrows in colonies in sandy banks and bluffs.
- Size
- 4.5 in long, about 0.5 oz (12 cm, 14 g)
- Habitat
- Open airspace over fields, water and towns; nests in cavities, earthen banks or on structures.
- Diet
- Small flying insects caught low over water and open ground.
- Range
- Recorded on 1,615 Breeding Bird Survey routes across 44 states, most concentrated in the Eastern Tallgrass Prairie.
- Family
- Hirundinidae · Aerial insectivores
- Conservation
- Least Concern
Notable Bank Swallow Trends
Bank Swallow has fallen sharply in surveyed states: down 74% on the route-weighted index since 1968.
Bank Swallow Population Forecast
If the recent trend holds, Bank Swallow is projected to stay roughly flat through 2029, near 0.62 (95% range 0.00–1.2). A 5-year backtest shows a typical error of ±39.2%, with 100% of held-out values landing inside the 95% band.
| Year | Projected index | 95% low | 95% high |
|---|---|---|---|
| 2025 | 0.73 | 0.11 | 1.3 |
| 2026 | 0.70 | 0.08 | 1.3 |
| 2027 | 0.68 | 0.06 | 1.3 |
| 2028 | 0.65 | 0.03 | 1.3 |
| 2029 | 0.62 | 0.00 | 1.2 |
Where the Bank Swallow Is Detected
BBS routes recording Bank Swallow, sized by most recent count.
Bank Swallow Population Trend by State
| Alabama | insufficient data | n/a | 3 |
| Alaska | -82% | 1976 | 91 |
| Arkansas | -53% | 1992 | 4 |
| California | +505% | 1971 | 27 |
| Colorado | -54% | 1973 | 35 |
| Connecticut | +77% | 1968 | 17 |
| Delaware | +10% | 1969 | 8 |
| Idaho | -63% | 1970 | 39 |
| Illinois | -95% | 1968 | 60 |
| Indiana | -82% | 1969 | 47 |
| Iowa | -92% | 1969 | 34 |
| Kansas | -82% | 1969 | 38 |
| Kentucky | +15% | 1977 | 10 |
| Maine | -92% | 1968 | 52 |
| Maryland | -82% | 1968 | 30 |
| Massachusetts | -53% | 1968 | 28 |
| Michigan | -44% | 1968 | 89 |
| Minnesota | -74% | 1969 | 73 |
| Mississippi | insufficient data | n/a | 1 |
| Missouri | -13% | 1972 | 27 |
| Montana | -75% | 1970 | 70 |
| Nebraska | -56% | 1969 | 40 |
| Nevada | +2% | 1996 | 11 |
| New Hampshire | -97% | 1968 | 24 |
| New Jersey | -67% | 1968 | 18 |
| New Mexico | -86% | 1973 | 5 |
| New York | -88% | 1968 | 108 |
| North Carolina | -88% | 1977 | 7 |
| North Dakota | -0% | 1969 | 51 |
| Ohio | -68% | 1968 | 49 |
| Oklahoma | -70% | 1969 | 16 |
| Oregon | +501% | 1971 | 43 |
| Pennsylvania | -85% | 1968 | 60 |
| Rhode Island | insufficient data | n/a | 1 |
| South Dakota | -81% | 1969 | 41 |
| Tennessee | +448% | 1980 | 12 |
| Texas | -92% | 1969 | 27 |
| Utah | -96% | 1974 | 31 |
| Vermont | -93% | 1968 | 24 |
| Virginia | -72% | 1972 | 15 |
| Washington | -69% | 1970 | 62 |
| West Virginia | -97% | 1976 | 16 |
| Wisconsin | -91% | 1968 | 86 |
| Wyoming | -5% | 1971 | 85 |
Bank Swallow Population Trend by Region
Bird Conservation Regions are the ecological unit for trends.
| BCR 2 | -68% | 1985 | 22 |
| BCR 4 | -79% | 1976 | 57 |
| Northern Pacific Rainforest | +53% | 1974 | 27 |
| Great Basin | -42% | 1970 | 129 |
| Northern Rockies | -80% | 1970 | 130 |
| Prairie Potholes | -2% | 1969 | 111 |
| Boreal Hardwood Transition | -92% | 1968 | 93 |
| Lower Great Lakes / St. Lawrence Plain | -84% | 1968 | 73 |
| Atlantic Northern Forest | -94% | 1968 | 122 |
| Southern Rockies / Colorado Plateau | -87% | 1974 | 45 |
| Badlands and Prairies | +1% | 1969 | 77 |
| Shortgrass Prairie | -97% | 1969 | 27 |
| Central Mixed Grass Prairie | -62% | 1969 | 54 |
| Oaks and Prairies | -10% | 1970 | 11 |
| Eastern Tallgrass Prairie | -90% | 1968 | 163 |
| Prairie Hardwood Transition | -86% | 1968 | 147 |
| Central Hardwoods | +7% | 1975 | 37 |
| Mississippi Alluvial Valley | -97% | 1980 | 5 |
| Southeastern Coastal Plain | -46% | 1989 | 8 |
| Appalachian Mountains | -95% | 1968 | 130 |
| Piedmont | -80% | 1968 | 26 |
| New England / Mid-Atlantic Coast | -74% | 1968 | 87 |
| Coastal California | -95% | 1972 | 11 |
| Tamaulipan Brushlands | -86% | 1970 | 10 |
Bank Swallow Conservation Status
Least Concern
The IUCN Red List rates this species as Least Concern. Our route-weighted index shows it down about 74% since 1968. 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.