Barn owls are one of the most widely distributed birds in the world and can be found on every continent except Antarctica. Despite their name, barn owls do not actually require barns or other human-made structures to thrive. However, they will readily nest and roost in old barns, abandoned buildings, and hollow trees if suitable habitat is available. This has led to the common name “barn owl”, though they are not true owls in the strictest sense.
Do barn owls nest in barns?
Barn owls sometimes nest in barns or other agricultural outbuildings, but they do not depend on these structures. Their habitat requirements are:
- Access to open hunting grounds such as grasslands, marshes, or agricultural fields
- Suitable nesting sites in cavities, crevices, or ledges
- Ample prey such as small mammals and other vertebrates
Old barns, abandoned buildings, hollow trees, and caves can provide the nesting sites barn owls need. However, they will also readily use nest boxes put up specifically for their use. The presence of old barns and outbuildings can benefit barn owl populations by giving them safe nesting options near good hunting habitat. But they are not essential for barn owls to persist in an area. The owls are also not specifically adapted to nest in barns, unlike some birds such as barn swallows.
Barn owl habitat and behavior
Barn owls can occupy a wide range of ecosystems as long as their basic needs are met. Some key aspects of barn owl habitat and behavior include:
- Grasslands, agricultural areas, forest edges, wetlands – Provide open hunting grounds
- Cavities, crevices, ledges, nest boxes – Used for nesting and roosting
- Feed primarily on small mammals like mice, voles, shrews
- Nocturnal hunters that locate prey by sound
- Do not build their own nests, dependent on existing cavities
- Non-migratory, occupy home ranges year-round
- Can coexist near human habitation
Due to their ability to hunt by sound and tolerate some human disturbance, barn owls can do quite well in proximity to farms, rural houses, and suburban areas that provide shelter and hunting habitat. Barn owls form monogamous breeding pairs and show nest site fidelity, often reusing the same nesting spot annually.
Barn owl populations and conservation
Barn owl populations dropped steeply in the 20th century in the U.S. and Europe. Intensification of agriculture and removal of old barns and hollow trees likely contributed to the decline by reducing nest sites. Barn owls are now considered an endangered species in several states. Conservation steps such as installing nest boxes and protecting grassland habitat have helped stabilize populations in some regions. Other barn owl population threats include:
- Habitat loss
- Vehicle collisions
- Declines in small mammal prey
- Pesticides reducing prey
- Climate change
Ongoing conservation and research programs monitor barn owl populations, contribute to scientific knowledge, and aim to further habitat protection for the benefit of barn owls and other species. This includes tracking occupancy rates of nest boxes and working with landowners to enhance barn owl habitat through sustainable agricultural practices.
Barn owls and rodent control
One reason farmers may appreciate the presence of barn owls is their potential to help control rodent pests. An individual barn owl may eat up to 1,000 small mammals per year. Rodents like voles and mice make up over 90% of the typical barn owl diet. Having owls around can therefore limit impacts of rodents on crops and stored grains. However, barn owls alone are unlikely to fully control rodent populations, especially rapidly multiplying species. Efforts to attract barn owls can be one component of an integrated pest management plan, but further control methods may also be required to protect crops and reduce disease risks.
Rodent Species | Estimated Consumed by Barn Owl (annually) |
---|---|
Voles | 400 |
Mice | 350 |
Rats | 50 |
Other | 100-200 |
As shown in the table, common rodent prey consumed annually by an individual barn owl include about 400 voles, 350 mice, 50 rats, and 100-200 other small vertebrates. Voles and mice make up the bulk of the diet. The appetite of barn owls for rodents may provide some biological control, but does not guarantee complete protection of crops and feed supplies from damage. Barn owl conservation should be treated as just one possible component of integrated pest management programs.
Attracting barn owls to farms and rural areas
If you want to attract barn owls to your property for rodent control or to conserve the owls, here are some tips:
- Put up barn owl nest boxes in undisturbed areas away from human activity
- Leave dead trees standing where feasible, for potential nest cavities
- Maintain areas of tall grassy vegetation as hunting grounds
- Avoid pesticide overuse so prey remains abundant
- Follow legal guidelines and best practices for barn owl boxes and conservation
Having a combination of grassy hunting habitat, intact cavities or nest boxes, and healthy rodent populations gives barn owls what they need. Be aware they may still only occasionally or locally reduce rodents, so additional management may be warranted. Consider participating in barn owl monitoring programs to help track populations over time. Enjoy their presence but avoid disturbing nests and give them adequate space.
Tips for installing barn owl nest boxes
If installing nest boxes specifically for barn owls:
- Use a box design made for barn owls with appropriate interior dimensions
- Place boxes 10-15 feet high sheltered from the sun and rain
- Orient entry holes away from prevailing winds
- Locate away from roads, noisy areas, and human activity
- Annual maintenance may be needed to clean boxes out
- Consider pairing boxes to give nesting and roosting options
Properly constructed and positioned nest boxes can provide excellent barn owl habitat. However, boxes left unchecked may become occupied by other species. Follow best practices to create nesting opportunities suited to barn owls.
Barn owls as sustainable pest control
Barn owls show how conservation of native predators can potentially reduce reliance on chemical pest control methods. While owl predation alone is not sufficient, as part of an integrated pest management plan they provide free, natural rodent control. This ecosystem service benefits farmers trying to reduce pesticide use and environmental impact. Promoting barn owl populations through habitat management represents a sustainable agriculture practice building on nature’s own rodent control agent – the barn owl.
Conclusion
In summary, while barn owls are often associated with rural barns, they do not inherently need barns to survive. Their key habitat requirements are accessible hunting grounds, cavity nest sites, and abundant small mammal prey. Barn owls readily adapt to nesting in human structures, but also occupy natural tree cavities and crevices. Conservation efforts can benefit barn owls by providing nest boxes where natural sites are limited. Having barn owls around helps control rodent populations, though other management practices are still likely needed. With proper habitat available, barn owls can persist in rural areas and provide natural rodent control, representing one part of sustainable agriculture systems. Their presence contributes to biodiversity and healthy ecosystems.