Quick Answer
Yes, short-eared owls do eat birds. As predators, short-eared owls hunt small mammals, birds, and reptiles to survive. Birds make up a significant portion of the short-eared owl’s diet.
Overview of the Short-Eared Owl
The short-eared owl (Asio flammeus) is a medium-sized owl found throughout much of the world. Some key facts about short-eared owls:
- Scientific name: Asio flammeus
- Average length: 13-17 inches
- Wingspan: 35-44 inches
- Average weight: 7.8-15.3 oz
- Lifespan: Up to 12 years in wild, up to 25 years in captivity
- Habitat: Open grasslands, prairies, meadows, marshes
- Range: North and South America, Europe, Asia, Africa, Australia
The short-eared owl gets its name from the small, barely visible ear tufts on the top of its head. These owls have yellow eyes and buff-colored plumage with darker brown streaks. Their undersides are lighter with thick brown barred patterns. Short-eared owls have broad wings and long tails that give them a distinctive silhouette in flight.
Short-eared owls are found in open habitats like grasslands, meadows, prairies, and marshes where they hunt for prey. They are opportunistic hunters and will consume any small animals they can capture including mammals, birds, reptiles, amphibians, and insects.
Short-Eared Owl Diet
Short-eared owls are generalist predators and eat a wide variety of prey. Their diet typically consists of:
- Small mammals – voles, mice, rats, moles, shrews, rabbits
- Small birds – sparrows, larks, blackbirds, starlings
- Reptiles – snakes, lizards, frogs, toads
- Insects – beetles, grasshoppers, moths
The relative proportions of these prey items can vary based on habitat and geographic location. But small mammals like voles and mice make up the bulk of their diet in most cases. Birds are also a vitally important prey item for short-eared owls.
Birds as Prey
Numerous studies have shown that birds make up a substantial part of the short-eared owl’s diet. Analyses of pellets, nest remains, and direct observation indicate that small birds are frequently consumed by these owls. Some key points about short-eared owls hunting birds:
- Up to 75% of prey remains in pellets were identified as birds in certain habitats
- Nestling short-eared owls were provisioned mainly with bird prey by parents
- Passerines like sparrows and larks are most commonly taken, but other familes are eaten too
- Will prey on anything from hummingbirds to pigeons and grouse
- Ground-nesting species and fledglings are especially vulnerable to owls
Short-eared owls often hunt during the day and use visual cues to locate prey. Their ability to find and capture birds in flight sets them apart from many other owl species. Certain local conditions like cyclic vole population crashes may force short-eared owls to rely more on abundant bird prey.
Hunting and Foraging Behaviors
Short-eared owls exhibit a number of interesting hunting and foraging behaviors related to catching birds:
- Still-hunting – Perch on elevated post and swoop down on prey on the ground
- Quartering flight – Fly back and forth over open ground while listening for prey
- Hovering – Hover in mid-air while scanning for prey and then dropping down on it
- Ground pursuit – Run along the ground after flushed birds before taking off in pursuit
Their long wings and sleek body profile make short-eared owls agile flyers. This aerial agility allows them to swiftly change direction during flight and gain speed in order to run down bird prey. Short-eared owls have even been observed capturing birds mid-air using their sharp talons.
One study in Scotland found that short-eared owls were significantly more successful at hunting birds when using hovering and ground pursuit techniques compared to still-hunting perched on posts. This demonstrates their specialized adaptations for hunting bird prey while on the wing.
Impacts on Bird Populations
Due to their appetites for birds, short-eared owls do exert predatory pressure on songbird and other small bird populations. However, in most cases this predation does not adversely impact the stability of prey species.
Several factors prevent short-eared owls from overexploiting bird prey:
- Generalist diet includes many small mammal prey as well
- Nomadic movements limit density of owls in one area
- Most prey are common species with high reproductive rates
- Predation is compensatory and replaces other mortality factors
There are exceptions in isolated habitats like oceanic islands where short-eared owls have greater detrimental impacts. But on continental land masses their influence is usually sustainable. Short-eared owl predation removes older, weaker individuals and helps maintain balance within food webs.
Special Adaptations for Hunting Birds
A number of anatomical and behavioral adaptations give short-eared owls an evolutionary edge when hunting bird prey:
- Daylight vision – Increased visual acuity in bright light compared to nocturnal owls
- Asymmetrical ear placement – Precise directional hearing to detect prey
- Stealth flight – Specialized wing feathers muffle sound while flying
- Cushioned feet – Soft feathers on feet allow silent approach on prey
- Curved talons – Sharp claws optimized for quickly grabbing and killing prey
These adaptations along with the short-eared owl’s speed, maneuverability, and aerial agility perfect it as a bird hunting specialist.
Notable Bird Prey Species
Short-eared owls have been documented hunting an extensive range of bird species across multiple families:
Bird Order | Families | Example Species |
---|---|---|
Passeriformes | Emberizidae, Fringillidae, Motacillidae, Passerellidae | Song sparrow, junco, lark bunting |
Charadriiformes | Charadriidae, Scolopacidae | Lapwing, dunlin, dowitcher |
Gruiformes | Rallidae | Yellow rail, sora |
Columbiformes | Columbidae | Rock pigeon, mourning dove |
Galliformes | Phasianidae, Odontophoridae | Northern bobwhite, ptarmigan |
Their choice of bird prey depends on factors like size, abundance, and vulnerability. Smaller passerines are widely eaten while larger prey like ducks, pheasants, and pigeons are taken opportunistically. Nestlings and fledglings of all types are easier targets for short-eared owls.
Hunting Bird Behavior by Region
There are some notable geographic patterns and preferences in terms of short-eared owls hunting different bird groups:
- North America – Voles, sparrows, blackbirds, meadowlarks
- Europe – Voles, pipits, skylarks, waders
- Hawaii – Seabirds like shearwaters, petrels, albatrosses
- Galapagos Islands – Mockingbirds, finches, doves
These preferences reflect the locally abundant food sources that short-eared owls have adapted to exploit. For example, they focus heavily on available seabird prey on isolated Pacific islands. Bird family composition also varies between continents – waders morecommon in Europe while blackbird predation more noted in North America.
Conclusion
In conclusion, birds clearly make up an important component of the short-eared owl’s diet across their worldwide range. While small mammals are eaten in higher quantity overall, short-eared owls frequently prey on varied bird species to meet their nutritional needs. Their unique adaptations like daylight hunting, aerial agility, acute hearing, and silent stealth flight allow short-eared owls to regularly hunt and consume bird prey. However, their generalist diet and other ecological factors prevent short-eared owls from negatively impacting most bird populations. Their role as predators of birds is simply part of the natural order and balance of ecosystems.