Burrowing owls (Athene cunicularia) are small, long-legged owls found throughout open landscapes of North and South America. They are considered an indicator species, meaning their presence reflects the overall health of the ecosystem they inhabit. Burrowing owls get their name from their habit of nesting underground in burrows dug by mammals like prairie dogs, ground squirrels, and badgers. Understanding where they are most commonly found gives insight into their habitat preferences and conservation needs.
Distribution in North America
In North America, burrowing owls are found from southern Canada through the western and central United States, south through Mexico and into central America. They are considered a grassland specialist, preferring open habitats including prairies, plains, deserts, and agricultural areas. Their breeding range centers around the Great Plains region.
Some key areas where burrowing owls are found in North America include:
- Western grasslands and deserts – Throughout the Great Basin and desert Southwest including southeastern Oregon, southern Idaho, Nevada, Utah, western Colorado, Arizona, New Mexico and west Texas.
- Great Plains – Primarily in Oklahoma, northwestern Texas, eastern Colorado, Nebraska, South Dakota, and southeastern Wyoming.
- Central Valley of California – An important wintering area, centered in the Imperial Valley.
- Coastal prairies of Texas and Louisiana – Wintering burrowing owls concentrate along the central and southern Texas coast and in southern Louisiana.
- Florida – Scattered breeding occurs in central and southern Florida, and the Florida peninsula hosts wintering owls.
- Mexico – Distributed across Mexico below 2,000 m elevation, with concentrations in northwestern Mexico.
Though widespread, burrowing owl populations have declined substantially over the last century due to habitat loss. They are listed as endangered in Canada, threatened in Mexico, and a species of special concern in many U.S. states.
Distribution in Central and South America
In Central and South America, burrowing owls occupy open habitats from Mexico south to Tierra del Fuego at the southern tip of Argentina and Chile. They can be found in grasslands, savannas, agricultural areas, deserts, and scrublands at elevations below 2,500 m.
Some regions where they are common include:
- Northern Colombia and Venezuela
- Central Brazil
- Peruvian coastal desert
- Grasslands in southern Brazil, Paraguay, Uruguay, and northern Argentina
- Pampas grasslands of central Argentina
- Patagonian steppe of southern Argentina
Though still widespread, some Central and South American populations are declining, particularly in agricultural areas where changes in land use have reduced habitat availability.
Key Habitat Features
Across their range, burrowing owls show selection for open, level to gently sloping landscapes with low vegetation suitable for nesting and foraging. Some key habitat features include:
- Short, sparse vegetation – Allows for visibility and hunting while walking or hovering in flight.
- Bare ground – Provides access to prey like insects and small mammals that burrowing owls capture while on the ground.
- Underground burrows – Provides nesting, roosting and refuge sites. Burrowing owls are dependent on the burrows dug by other species and rarely excavate their own.
- Low slopes – Facilitates burrow drainage to prevent flooding.
- Elevations below 2,500 m – Represents their physiological limit due to their adaptations for open, arid environments.
These habitat features may be found in native grasslands and shrublands as well as some agricultural areas and urban environments. Loss of suitable nesting burrows is a major limiting factor across the owl’s range.
Climate Factors
Burrowing owls inhabit relatively dry climates throughout their range. They are well-adapted to arid and semi-arid grasslands and deserts. Some key climate factors where they occur include:
- Annual precipitation less than 40 inches (100 cm)
- Little precipitation during breeding season
- Areas with frequent drought periods
- Regions with high diurnal and seasonal temperature variation
- Annual temperature ranges from freezing to over 100°F (38°C)
These climate patterns characterize many of the prairies, plains, and deserts burrowing owls occupy. Their adaptations for drier environments include specialized feathers for thermoregulation, ability to withstand high temperatures, and ability to survive without free standing water.
Threats and Conservation
Though still widespread, burrowing owl populations have declined substantially over the last 100 years. Major threats include:
- Habitat loss due to urbanization and conversion to agriculture
- Reduced availability of burrows due to control of prairie dogs and other burrowing mammals
- Habitat degradation from overgrazing by livestock
- Vehicle collisions in areas near roads
- Predation by dogs, cats, and other urban wildlife
Conservation efforts focus on protecting remaining grasslands from development, maintaining populations of burrowing mammals, installing artificial burrows, and reducing vehicle collisions. Their adaptability to some human-altered environments, if properly managed, may assist in their conservation.
Conclusion
Burrowing owls inhabit open, arid environments with low vegetation and available burrows for nesting. They reach their highest densities in prairie and desert regions, particularly in the Great Plains of North America. Though adaptable to human disturbance in some regions, habitat loss poses the greatest threat to most populations. Their status as an indicator species means protecting burrowing owl habitats will benefit many other grassland and shrubland species experiencing decline.
