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Owls stand out among all living bird groups. These slightly
anthropomorphic winged creatures have conquered the night, while nearly
all other birds are confined to the daylight. But despite what you may
think you know about owls, a lot of information escapes the grasp of
common knowledge. And our wise friends have quite a few interesting
stories to tell.
10 Extreme Blood Flow Adaptations
Owls vary greatly in size, appearance, and coloration, but they all share one thing—the ability to
turn their head
270 degrees. In order to perform this task, their necks contain 14
vertebrae, rather than the usual seven found in “normal” birds. While
the neck vertebrae provide the range of movement, many animals—such as
humans—would suffer traumatic arterial injuries and blood flow
interruptions from such extreme motion.
In their attempt to understand how such capabilities exist,
scientists have discovered that owls have special blood-pooling systems
that collect blood to power their brains and eyes when neck movement
cuts off circulation.
Other awesome owl adaptations include alternative blood vessel routing
and air-cushioned vessel casings to prevent rupture and stroke during
violent head motion.
9 Owl Pseudo-Cannibalism
Cannibalism technically refers to an act of predation against a
member of the same species. And it may come as a shock to the novice
bird enthusiast that owls aren’t really averse to
eating owls
of a different species. Great horned owls are actually the chief
predation threat to the smaller barred owl. In turn, barred owls will
eat even smaller owls.
Expansion of barred owl distribution from southeastern swamps into
the Pacific Northwest is considered to be a partial cause of declines in
Western screech owl populations due
owl-on-owl predation.
Apart from other owls, there are few avian species that will actively
hunt them for food. Fortunately, you can help: If you’re one of those
people who plays recorded bird music to try to draw out birds, stop it.
It may cause the owls to call in response, giving away their location.
8 Crazy Eyes
Owl vision is quite unconventional. Their eyes are
extremely large
and nearly touch inside the head. Owl eyes are also completely immobile
and cannot be considered true “eyeballs,” since they’re actually
tube-shaped. Binocular vision lets owls fully focus on their prey and
boosts their depth perception. However, it also makes the owl more
vulnerable to predators, which include other owls and mobs of irate
songbirds. Owls can rotate their heads 270 degrees, which compensates
for their forward-facing vision and immobile eyes.
7 Some Eat Plants
Owls are among the purest of carnivores in the bird world. Occupying a
fraction of the world’s species total, these night hunters won’t stoop
to scavenging in most cases. However, one species is rather unique in
its conquest of the night. In a freak occurrence among birds, the elf
owl not only feeds on small animal prey, but adds
fruits and seed parts to
its diet. These owls engage in a sort of “cultivation” where they
spread dung around their nest sites in a bid to attract dung beetles.
These enterprising “birds of prey” seem to favor prickly pear berries
and the fruits of the tasajillo cactus for the not-so-predatory portion
of their diet.
6 Many Owls Don’t Hoot Or Screech
Owls are stereotyped for their hooting calls, but a number of species
don’t hoot at all. Snowy owls of the far north produce seabird-like
squeaking calls that are a far cry from a typical owl call. Small owls,
such as
pygmy owls make dull whistling sounds. The most flagrant example is the
screech owl.
It doesn’t screech at all, but gives a “bouncing” series of rapid,
whistling toots. The unearthly screeching calls of juvenile great horned
owls often lead to false reports of a screech owl being heard.
5 They Eat Larger Prey Than You Think
Eagle owls are among the largest winged hunters on the planet and
combine their size with incredible ferocity. They will eat almost
anything and stop at nothing. Veraux’s
eagle owls
will carry off adult vervet monkeys, and young warthogs aren’t much of a
challenge either. They will also target fish-eating owls of nearly
equal size. Eurasian eagle owls are just as fierce as their African
cousins and have killed normally invulnerable golden eagles.
According to one report, a young wolf was attacked, while small deer and even foxes are
taken with regularity.
In one spectacular attack, a Veraux’s eagle owl killed a massive,
cobra-eating secretary bird. Herons have been eaten, but strangest of
all is the owl’s fondness for hedgehog meat, which seems to dominate its
diet wherever available. While most species recoil from the mass of
quills, this owl uses its massive, scaly talons to simply peel the
hedgehog’s quills off.
4 They Live In Cacti
In North America’s Sonoran Desert, saguaro cacti can grow over 10
meters (about 30 ft) in height and form entire forests. The excavations
of specially adapted woodpeckers known as gila flickers are used as
nesting sites by elf owls, which
peer out from the cactus with bright, yellow eyes.
The cactus forests are also inhabited by another small owl, the
ferruginous pygmy owl. This far more aggressive, bird-eating owl is
slightly larger and will also nest in saguaro and organ pipe cacti.
Continuing the theme, huge great horned owls often nest in the crotch of
such a cactus
3 Owls And Human Culture
While the stereotype of the “wise owl” is well established, owls can be regarded as demonic symbols or
harbingers of doom.
Connections to witchcraft are often made as well. Owls have also risen
to prominence as icons in popular culture, such as the famous Hedwig,
the snowy owl featured in the
Harry Potter series.
Apart from cultural significance, owls have been used by humans in
the sport of falconry. Falconer’s owls may be trained to the glove and
sent off in pursuit of a wide range of quarry,
such as rabbits.
Generally, owls are catlike birds—nocturnal and hard to train. While
some of the larger owls distinguished themselves as hunting companions
in Europe, their employment as falconry decoys is more common. Hated and
harassed by hawks, an owl would be tethered to a perch to lure in its
enemy for capture.
2 Weird Relatives
Owls are often referred to as “birds of prey,” but these nocturnal
hunting birds share no relation to hawks, eagles, or falcons, which are
known as diurnal birds of prey. Taxonomy is a controversial and changing
science, but both the
Sibly-Alquist model
of bird classification and alternative methods identify owls as ranking
closer to kingfishers, hummingbirds, and even songbirds (like sparrows)
than to hawks. Hawks and other diurnal birds of prey are relegated to
the more primitive reaches of avian origins, near the cranes, herons,
and other prehistoric-looking birds.
Despite appearing hawklike, owls are kissing cousins of the humble
nightjars,
also known as “goatsuckers.” Similarities between hawks and diurnal
birds of prey are apparent, especially when an owl’s feathers are
parted, revealing a large, hawklike bill, but convergent evolution is
the agent of cause—not relation. Nocturnal and diurnal predatory bird
orders fill similar ecological niches but avoid competition by hunting
within their opposite “hours of operation.”
1 They’re Silent Killers
A large part of what makes owls such effective hunters is their
ability to hear exceptionally well, while remaining silent themselves.
However, this requires some interesting adaptations. Special hooks on
the front of the owl’s wing feathers act as airflow silencers, while
“fraying” on the trailing edges offer silent flight that allows the owl
to
swoop behind prey undetected.
To produce truly cutting-edge powers of auditory detection, owls fly
in the face of conventions of animal symmetry. Several owl genera have
asymmetrical ears, located at different heights on the owl’s head. This
allows the owl to pinpoint the location of sounds in multiple
dimensions, helping to quickly guide the bird into striking range.
