The main differences are that they are elusive and nocturnal, for the most part. You are far more likely to hear than to see one, but even that is hit or miss. They are carnivores, whereas most birds I’m familiar with tend to be more omnivorous. Several once common species are in sharp decline. Those dependent on nocturnal, decent-size flying insects seem to be in trouble, as are those that eat vertebrates. Some vertebrate prey is also dependent on the aforementioned insects, (bats) so all are affected by declining insect populations and habitat destruction.  Some large owls are apex predators, most other birds are not. Using hearing to hunt is also unusual, as most birds are primarily visual. 

Most owls are night hunters with exceptions, like the Northern Hawk owl.  And I must say, the barred owls that make our property their territory…hunt at night and during the day.  I often see one perched nearby our bird feeder station.

I found the explanation and diagrams showing an owl's digestive organization very interesting.   I learned that there are a few other bird species that produce pellets, but none of the pellets are as formed and as big, like the owl pellets, depending on the size of the owl, of course.  Fascinating.  Now I understand better the process of pellet production for Owls.  Examining the contents of owl pellets is very revealing about what they eat.  Insects and worm parts don't show up, of course.  I was fascinated to learn that some owls eat earth worms, creatures that they did not evolve with in North America.  Of course, other birds, like Robins have adapted to hunt for earth worms.

Interesting note, Red Foxes in North America do not hunt for earth worms, but their cousins in Europe, where earth worms evolved, do.  So, owls are better at adaptation than Red Foxes in N.America.

Not so much lifestyle, but I didn't previously realize that owls have zygodactyl feet, like woodpeckers.

Owls are cavity-nesters and nest-box-nesters, much like chickadees, House Wrens, bluebirds, and Tree Swallows. That owls using nest boxes don't do much to make a comfy bed for their owlets made me think of the scraggly nest of the Mourning Dove.

I never gave any thought to owl migration, or lack of it. Makes sense that they don't go far, if they go at all, since migration is generally driven by changes in the food supply.

Speaking of food supply, I was rather horrified to learn that some species of larger owls will prey on their more diminutive cousins. Reminds me of what able hunters Cooper's Hawks are on songbirds. I wish there were a way to entice raptors to leave the native birds alone and instead pick off exclusively the non-natives, especially the European Starlings and House Sparrows.

Unlike many songbirds, owls don't build their own nests, and don't expend much energy preparing their nest sites. They use cavities in trees (like those created by woodpeckers), or take over other nests (like squirrel nests). They produce several eggs over a period of days, but they don't hatch at the same time. Like other raptors, the female sits on the nest while the male is busy hunting for food. Most owls don't migrate like many songbirds do. They are permanent residents in their range, and defend their territories. Owls produce large pellets by regurgitating undigested food, and many other species do too. But owl pellets are large and easy to identify, unlike the pellets of other bird species. I know that great horned owls are early nesters. In the Pacific Northwest, an owl pair might start preparing a nest in December. The owlets need the extra time to grow to the adult size before they are ready to live on their own.

Owls are nocturnal while most other birds are diurnal (and have poor night vision). Owls also have much duller colors than many other birds, this helps them hunt better. Though not exclusive to owls, they regurgitate pellets of indigestible fur and bones after a meal.

For this contribution I am going to compare to the bird called a Merlin Falco columbarius.  This is a bird that I have seen on two occasions in my yard, most recently about one month ago (December) near my bird feeder.  I live in Western Oregon and recently there was a clear cut in my vicinity.  I believe that this has concentrated birds at the edge of what was once forest and the concentration of smaller birds has raised the attention of predators, including predatory birds.

A merlin is a falcon, so one more likely to be seen during the day.

Similar to many owls their coloration of brown, vertical stripes on their front makes this a difficult bird to see hence they are well camouflaged.  Each time I have seen them they sit very still on a perch, but it is the downward facing tail with bands that give them away.  They are similar to kestrels or peregrines but appear stockier with a broad chest area.

Similar to owls they do not build their own nests but instead will take over residence of larger predatory birds like hawks as well as crow nests during their breeding season.  Their habitat is similar to many owls in that they are most likely to be inhabiting semi-open areas like forest edges or grasslands.  Their diet is specific to small birds, some owls eat birds, but like all falcons these birds are diurnal.  The Merlin is far more specialized in being a predator of smaller birds - hence why I saw them near my feeder and all the small birds were cleared out that afternoon of seeing this remarkable bird.  To find this bird, which reportedly has been said to be seen near towns or wherever there are concentrations of Dunlins (like marshes) it is best to look for snags of old trees where it is likely watching for prey.   Similar to an owl they make a fast descent from their perch and capture their prey with fierce talons.  I have not seen this in person, but I can only imagine how decisive this effective predator must be in its specialized niche.

Sources:

Merlin Overview, All About Birds, Cornell Lab of Ornithology

Birds of the Willamette Vally Region by H. Nehis, T. Avers and H. Opperman (2005).

Owls hunt at night and regurgitate pellets. They eat small mammals. Songbirds are more active during the day, they don't regurgitate pellets and eat seed and suet.

An interesting thing happened two seasons ago, a GHOW took over an Osprey nest which was built over four lanes of traffic on the horizontal street sign that marked the local high school.  It became the most popular birding spot in Englewood, FL.  Many observers were worried that the two young owlets might branch before being able to fly.  First season, not a problem, both owlets fledged.  This past season, one of the parents was hit by a car and died, but the solo parent raised the single chick.  The chick did try to branch on the metal piping and fell into the road.  Luckily an observer scooped it up off the road, took it to a local rehab, which later released it in the nearby environmental park.  The parent and owlet were reunited.  I petitioned the park to install an osprey platform away from the road with the hope that a safer, alternative nest site will prevent future issues.  

I compared the Great Horned Owl with the Red-tailed Hawk, because I commonly see and/or hear both similarly sized raptors, more often the hawk since it is diurnal and likes to perch on street lamps. They are both generalist predators that hunt in the same wide variety of areas with a dietary species overlap of some 50%, according to an abstract. They both will eat the local rattlesnakes, and the stronger owl (talon strength is equal to and up to twice that of the hawk) will sometimes make a meal of the hawk. They are both perch hunters, but the hawk has speed to catch prey, while the owl has stealth. DAY OR NIGHT: While the hawk is diurnal, the owl is mostly nocturnal. MEMORABLE FIELD MARKS: cinnamon-red tail of hawk; horn-like ear tufts of owl. MEMORABLE VOCALIZATIONS: hawk’s iconic cry for movie soundtracks “KEE-EER!”; owl song mnemonic “WHO’S AWAKE? ME TOO.” NEST BUILDERS: The Red-tailed Hawk builds a nest of sticks with its mate, which it rebuilds in another location the following year if a Great Horned Owl claims it first as the owls are not nest builders.

I didn't realize until last year while watching the barred owl cam that owlets typically leave the nest before they can fly. I'm always on edge watching them climb up tree trunks and hopping from branch to branch!

I was surprised to learn that owls don't make their nests but use another bird's. I'm amazed by how many birds nest in the tree cavities or next boxes.

Comparing the Barred Owl to Osprey:

SIZE: Barred Owls are smaller than Ospreys. // On average: Barred owls have a Length of 21 inches; Wing Span of 42 inches; Weigh 1.6 pounds (720 grams). // Ospreys have a length of 23 inches; Wing Span of 63 inches; and Weigh 3.5 pounds (1600 grams). ////

COLORS AND MARKINGS: Barred Owls and Ospreys are distinctively different in colors and markings. It is extremely unlikely that a Barred Owl can be mistaken for an Osprey. // Barred Owls have mottled brown and buffy coloring. They have lots of spots, bars, and stripes, allowing them to blend into their habitat easily. Barred Owls have a distinctive rounded face with a facial disc. // Ospreys are more boldly marked black and white that include a white forehead and a dark mask; spots on their chest. ////

RANGE: Barred Owls are found in North America, northern west coast, northern Canada; Eastern Canada and USA. Wherever there are mature mixed forests. // Ospreys are found in Northern Canada; Northern USA in the summer. // The Barred Owl and Osprey differ in that the Barred Owl is a resident, non-migratory bird. Ospreys do migrate and winter in Northern South America, passing through Central USA and Mexico as they migrate.  ////

HABITAT AND NESTING CHOICES: Barred Owls are often found near water, they are always in mature forests with hidden nests in tree cavities that are 20-40 ft above ground. // Ospreys must live within view of either salt or fresh water. Osprey nests, though high above ground, are open and exposed; always within 12 miles of water. // Both birds will use man-made structures for nests: Barred Owls will use nest boxes; Ospreys use platform nesting areas. ////

PREDATORS: Both Barred Owl and Osprey share the some of the same predators: the Great Horned Owl, raccoons, snakes, fishers. // Barred Owls must look out for Northern Goshawks and weasels. // Osprey must look out for Bald Eagles. ////

HUNTING: Barred Owl and Osprey hunting strategies differ. Barred Owls are nocturnal hunters. Barred Owl will choose to “Sit and Wait” or “Perch and Pounce method using both sight and hearing. Barred Owls have a facial disk and ears where one is placed higher on the head than the other. These two aspects of the Barred Owl allow for excellent hearing. Specialized feathers that mute the sound of feathers passing over one another in flight are unique to Barred Owls. With their exceptional hearing, Barred Owls can hear small mammals tunnel under snow.// Osprey are diurnal hunters. Ospreys differ in hunting techniques and do not use hearing, but only sight. Ospreys will circle above water, hover then dive down  to the water to grab fish using feet that have barbs to keep fish from slipping away. The success of an Osprey’s hunt is weather dependent; especially on wind speed; the calmer the day, the more successful the hunt. // Both the Barred Owl and the Osprey have binocular vision, forward facing eyes, which is essential for hunting. Both the Barred Owl and the Osprey have zygodactal feet with two toes forward and two toes back, with the uniqueness of allowing one toe to shift forward and backward. Both birds strike with their feet first to capture their prey. ////

FOOD: There are differences in food choices between the Barred Owl and the Osprey.// Barred Owl will choose small mammals such as squirrels, chipmunks, mice, voles, rabbits, amphibians and reptiles. // Osprey live exclusively on fish. ////

SEXUAL MATURITY: Barred Owls may breed for the first time at about 2 years old. // Ospreys are at least 3-4 years old at first breeding. ////

BREEDING: Both Barred Owls and Osprey are monogamous.// Barred Owl pairs retain and defend their territory throughout the year. // Ospreys migrate, but return to the same nest every year. // Both Barred Owls and Osprey engage in courtship feeding where the male feeds the female. // Clutch size differs slightly. Barred Owls have 1-3 eggs and lay one clutch per breeding season. // Ospreys have 2-4 eggs and lay one clutch per season. ////

CHICKS and YOUNG: In both the Barred Owl and the Osprey, chicks are altricial after hatching. Males bring food to the nest while the females incubate the eggs and feed the young in both species.// Barred Owl chicks will engage in ‘branching’ at five weeks. Branching is when owlets leave the nest explore the world from their places on branches. They may fledge between 6-8 weeks. // Ospreys remain in their nests until they are fledged at 6-7 weeks. They will remain in the area for 1-2 months before setting off to South America.  ////

CONSERVATION: Barred Owls and Ospreys are both rated as Least Concern on the International Union for Conservation of Nature’s (IUCN) Red List of Threatened Species. ////

PERSONAL LIFE LIST: I have yet to add a Barred Owl to my life list. I am ever hopeful that I will see one soon. // I have watched Ospreys weekly every summer at the same platform nests since I began birding in 2020 including nest building, incubation period, interaction between males and females, feeding young, and watching parents teach young to use their wings.

Owls, like most other birds, fly, hunt for food, and raise their young. Some differences are how they don't make their own nests, instead they use tree cavaties or abandoned bird nests (eagle, hawk, raven...) Owls are also known for regurgitating indigestable food in pellets- this can be seen as a similarity and a difference as many other birds do produce pellets, but owls are known for them because of how large the pellets are.

Owls are very similar to other raptors, but they are incredibly adapted to hunting at night using their sight and hearing. I was suprised that larger owls can hunt smaller ones and that they don´t make their own nests.

 

I think it is very hard to tell young owls apart from each other because of the fluff and feather patterns.

If you compare owls to other raptors like eagles, I was surprised to learn that owls do not make their own nests. Instead, they inhabit tree cavities, man-made structures (such as chimneys) or abandoned nests, including abandoned bald eagle nests. Another surprising fact is that non-migratory owls don’t always reuse the same nest but move around depending on prey availability. While Eagles are active hunters’ owls use different strategies, such as the “sit and wait” method. Like owls, which can be migratory or non-migratory, eagles may be fully migratory, partially migratory or resident. However, most eagles migrate due to food-scarcity, whereas snowy owls, an irruptive species, migrate south not from a lack of food but due to booming lemming populations. A surplus of lemmings leads to increased snowy owl population, triggering migration south due to increased competition. Eagles and owls rarely interact since they hunt at different times (diurnal vs nocturnal). However, as apex predators, eagles also prey on smaller owl species. Both eagles and owls produce pellets, though eagles do so less frequently, and their pellets are smaller pellets and less compact.

Owls are nocturnal while most other birds are diurnal.  Many other things like laying eggs and raising young are similar to other birds.

Owls, like most other birds, incubate eggs and defend and feed their young until they are ready to take off on their own. They will breed more successfully in the presence of plenty of food. Unlike many birds, they don’t build their own nests and take over suitable accommodations from others. They also regurgitate pellets instead of only eating what they can digest. Some migrate, but most are permanent residents in their ranges as long as there is plenty of food.

I knew that owls took other birds' nests, and they sometimes even hunt birds. Owls being mostly solitary, unlike a lot of other types of birds, did not surprise me either, but I did not know that some would nest together.

Owls fly, hunt for food, lay eggs, and raise their young like other birds. But they definitely have their own niche. They hunt at night. They use nests they find, rather than building their own nest. And most birds don’t regurgitate pellets like owls do.

Many birds migrate; most owls stay in one place year-round. From time to time the Snowy Owls move south, much to the delight of birders in the Seattle area. I’ve seen Snowy Owls a couple of times. These gorgeous birds are easy to spot here since we normally don’t have snow on the ground.

The fact that owls are less social and more solitary than other birds definitely stands out to me. However, the way that the mother owls care for the eggs and the father owls find food for them is similar to the roles of parents with other bird species.

Similar:

-like the potus, some owls have cryptic plumage, they hunt at night and they eat insects -an example is the Eastern Screech Owl

-like all raptors, they have very strong talons and a broad diet;  the talons are adapted to the particular food source - for example, a fish owl has large talons to catch fish similar to the golden eagle

Different:

-owls are different from other birds in that they sometimes use the abandoned nest of a rodent

-with some exceptions, other birds do not regurgitate pellets

I'd never previously given thought to the differences in hunting styles between species of owls.  Some hunt by sight and others totally by sound.  Thinking about the night hunters, relying upon listening for prey, and then successfully catching the prey is pretty amazing to me.   And I come back to the Great Gray Owl, who has been known to catch mice in 18 inches of snow..by sound.  So fantastic.

They are similar in the sense that they mate, lay eggs in some sort of nest, incubate their eggs, raise their young.

The main difference is the fact that they are active at night, whereas most other birds are active during the day.

The shape of their eyes and the location of their eyes and ears in their skull is also different.  How they utilize sight and hearing to find food explains why these differences are so pronounced.