Short-eared Owl Wednesday

Time for the second owl post of the week! Today’s featured owl is the Short-eared Owl, one of the most widespread owls in the world. It’s Latin name is Asio flammeus, translated to “flame-colored horned-owl”.

Short-eared Owl (Asio flammeus)

Description:

Short-eared owls are sandy-colored, medium-sized owls. Their short ear tufts are so tiny they are almost impossible to see unless you are close to the owl and it’s alarmed or agitated. Their underparts are heavily streaked and their upperparts are brown with white and buff. Males are grayer than females with whiter undersides/underwings. Their facial disks are lightly streaked and whitish with blackish triangular spots around the eyes. Short-eared Owls have very short tails and round heads. Juveniles are downy, and as they start to get adult plumage, their facial disks are black with white crescents with a white “mustache” chin.

Short-eared_owl_(Asio_flammeus)_Photograph_By_Shantanu_Kuveskar
By Shantanu Kuveskar (Own work) [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)%5D, via Wikimedia Commons
Range:

Short-eared Owls live throughout most of the Northern Hemisphere, including North America, Asia, Europe, and the Middle East. They are also found in the southern part of South America and on islands including Micronesia, the Caribbean, Hawaii, and Galapagos. In North America they are residents in the American West, parts of Canada, and Cuba. They spend the summers throughout Canada and winters in the Midwest and Northeast. Irregular irruptions can be found in the Southwest and Southeastern United States. The Caribbean population regularly invades Southern Florida.

Habitat:

Open country, such as grasslands, marshes, prairies, farmland, dunes, and tundra.

Diet:

Mainly meadow voles, but other small mammals such as mice, muskrats, moles, rabbits, pocket voles, and weasels. Also known to eat large insects and small to medium-sized birds. Short-eared Owls hunt most actively during dawn and dusk, but can be found hunting in daylight. They soar low to the ground and hover over their prey before landing on it.

Breeding/Nesting:

Males perform a “sky-dancing” display which include impressive spiraling flights, diving, calling, and wing-clapping. They will start courting in late winter, but pair bonds don’t usually last for the season. Nests are usually just a small depression in the ground, but Short-eared Owls have be occasionally known to also nest in trees with Long-eared Owls.

Short-eared Owls have one brood per year with the average clutch size of 5-6 eggs. However, when prey is abundant, it’s possible for the female to lay up to 11 eggs. The female incubates the eggs for 21- 31 eggs and hatching is asynchronous (meaning the eggs hatch over a number of days, not at the same time). The male will bring food to the female who will feed and brood the owlets. The owlets will usually leave the nest on foot at 12-18 days and can start to fly around 27 days.

Vocalizations:

Bark calls are given by both females and males, a nasal and harsh eee-YUURK! that can be short or drawn out, or a short rik-rikr-rik!.  Males hoot during courtship activities.

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Short-eared Owl (Image by Gregg Thompson via birdnote.org)

Conservation: 

Still widespread, but have declined by 50-80% in its North American range, mainly due to the fact that these owls are grassland specialists. They are listed as “endangered” or “special concern” in 26 states. They are still relatively widespread in other parts of their range. The Caribbean populations of Short-eared Owls have been expanding. Habitat restoration program have help populations improve.

Fun Facts: 

  • They are one of the few owl species to construct their own nests.
  • Hawaii’s only native owl is the Pueo, a subspecies of the Short-eared Owl.
  • Males can be extremely aggressive towards other males in the territories. They will duel by flying towards each other, locking talons and tumbling to the ground. They let go right before they hit the ground.

 

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Happy Owl-o-ween!

Happy Halloween everyone! Or should I say happy “Owl-o-ween” instead? I apologize that I didn’t have time to write an Owl Wednesday last week, so I wanted to make it up with a special owl post for Halloween.

Owls are mainly nocturnal, so many people associate them with darkness and mystery. At this time of year it’s not uncommon to the see owls in scary movies/shows and on Halloween decorations. It’s easy to see why people would find an owl in the night menacing. They have large glowing eyes, bellowing calls, and heads that they can make turn up to 270 degrees. Since ancient times, owls have fascinated cultures around the world and have become part of their folklore and superstitions.

Here are few spooky Halloween superstitions:

  • Owls and witches are often associated with each other. Some people believed that owls were used as messengers by sorcerers and witches. The Romans believed that witches could turn themselves into owls and swoop onto newborns to suck their blood.
  • The Hopi Indians believed that Burrowing Owls, called Ko’ko, were the protectors of the Underworld and the gods of death.
  • Many cultures have associated owls with death. An Appalachian mountain legend states that if you hear an owl call after midnight then death is coming. Many European plays and poems use owls as the symbol for destruction and death. However, a British Isle legend states that if you find an owl feather, you can use it to repel the negative forces that seeing an owl can bring.
  • Owls are often connected with sorcery in parts of Africa. If an owl is tied to a house, then it’s said that a powerful shaman dwells there. Owls also help shamans communicate with the spirit world.
  • In England, an owl screeching on a cold night meant that there was an impending storm.

Not all legends about owls are negative though:

  • The Aborigines from Australia consider owls sacred and think they are the spirits of women. Therefore, if you see an owl on the way to harvest, it will be good year for crops.
  • Some Indian cultures, such as the Dakota Hidatsa and Lenape thought of owls as protective spirits and guardians, especially for brave warriors. The Tlingit tribe would go into battle hooting like owls to strike fear in their enemies.
  • Athena, the Greek Goddess of wisdom, choose the owl as her one of her favorite birds after banishing the mischievous crow. Her owl was the Little Owl (Athene noctua) and they lived in abundance throughout the Acropolis.  It was believed that owls had an “inner light” that gave them ability  to see in the dark. Athena’s owls were a symbols of guidance, protection, and wisdom. It was said that if an owl flew over a Greek army, then victory would be forthcoming.

Some of my favorite legends from the Pacific Northwest tribes are about the Raven, a magical creature who is considered both a hero and a trickster. There is an  Inuit legend about the Raven and the Snowy Owl. Here’s one variation of this tale: the Raven and the Owl were making clothes for each other. The Raven made the Owl a lovely dress of black and white feathers. In return, the Owl made Raven whale-bone boots and a white dress. Owl tried to fit Raven’s dress, but Raven could not stay still. Owl became so frustrated that she threw a pot of lamp oil at Raven. The oil soaked through the dress and that’s how the Raven became black.


The folklore I listed above is just the tip of the iceberg when it comes to owl mythology. Owls have been both admired and fear of hundreds of years, but through scientific research we know that owls are a vital part of the ecosystems in which they live. One thing is certain: that owls have captured our imaginations and will continue to do so.

Happy Owl-o-ween!

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(Image via animals.desktopnexus.com)

Elf Owl Wednesday

Last week we learned about one of the tallest owls in the world, the Great Gray Owl.  This week we’ll go to the other extreme: the Elf Owl, which is the smallest owl in the world.

Elf Owl (Micrathene whitneyi)

Description:

Standing at around 5 inches in length, the Elf Owl is no larger than a sparrow or small thrush. These tiny owls have brown/gray upperparts and white/cinnamon colored barred stripes on its underparts. Their legs are relatively long and covered with small bristles. Elf Owls have piercing yellow eyes that are surrounded by a black rim. Over the eyes there is a narrow white eyebrow. Other owl species have 12 tail feathers, but Elf Owls have only 10 tail feathers.

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Elf Owl (Image via birds-of-north-america.net)

Range: 

Resident of Baja, California  and Central Mexico. Breeds (summer) in parts of Arizona, New Mexcio, Texas, and Mexico. Winters in Mexico.

Habitat: 

Sonoran saguaro deserts, large mesquites, wood canyons, riparian woods, montane forests of oak, thorn-scrub. Does surprisingly well in suburbs, but urbanization is a threat to this species.

Diet: 

Almost entirely insects, scorpions, spiders, but may rarely eat small vertebrates such as rodents, lizards, and small snakes. Elf Owls are crepuscular, meaning they forage most actively at dawn and dusk. They forage while flying, hovering, swerving, or grabbing insects off of trees.

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Elf Owl with a scorpion (Image via pinterest)

Breeding/Nesting:

When male Elf Owls return to their breeding grounds, they will pick multiple potential nesting sites. Females will arrive later, and the male will sing from his cavity entrance to attract her attention. Once the female approaches, the male will continue to sing from inside his cavity to convince the female to go in and mate.

Elf Owls do not make their own cavities. In their Sonoran desert habitat, they rely on existing holes from woodpeckers such as the Acorn, Ladder-backed, and Gila Woodpeckers. In other habitats, they will nest in whatever large trees are available such as cottonwoods and sycamores. Although Elf Owls only stay with a mating partner for one season, they may use the same nest site for up to 3 years.

The female will incubate 3 white eggs for about 2 weeks (although 1-5 eggs is possible). She starts incubating once the second egg is laid. The hatching is asychronous; the first 2 eggs tend to hatch together while the third hatches a few days later. The owlets will nest for about 4 weeks. The parents will encourage the young to fledge by withholding food. An astounding fact about Elf Owls is that they have around a 90% nest rate, the highest of any owl in the world.

Vocalizations:

The males are known for a “chatter call”, 6 or 7 rapid squeaky notes that are higher pitched in the middle.

Conservation: 

Locally common or abundant in manyareas of it’s range, but sharply declined in the lower Colorado River. Population trends are unclear, but they face threats such as urbanization, habitat loss, frequency of wild fires, and droughts.

Fun Facts: 

  • There are 4  subspecies: M. w. whitneyi, M. w. sadfordi, M. w. grayson, and M. w. idonea.
  • It’s assumed that owls migrate individually, but there’s some evidence that Elf Owls may sometimes migrate in small flocks.

Great Gray Owl Wednesday

This week’s featured owl is the captivating and mysterious Great Gray Owl of the northern boreal forests.

Great Gray Owl (Strix nebulosa)

Great Gray Owls are one of the tallest owls in the world, standing at around 3 feet tall with a 5 foot wingspan. But don’t let it’s height fool you; it’s body size is an illusion. Weighting at only 2.5 pounds, Great Gray Owls have a small body core and an impressive number of fluffy feathers that make them seem bigger than they really are. Other North American owls, such as the Snowy Owl and Great Horned Owl are much larger in mass.

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Cross-section taxidermy from the Zoological Museum in Copenhagen shows it’s body core compared to its feathers (Image by FunkMonk via wikimedia commons)

These owls sport beautiful silvery gray, white, and brown plumage. They have long tails and huge facial disks that have gray and brown concentric circles. In between their bright yellow eyes, Great Gray Owls have two pale arcs that form an “X” shape. Another distinctive feature is the white “bow tie”, which are patches of white feathers on their throats. Females are slightly larger and darker than males.

Range:

Canada and the Pacific Northwest, as well as Scandinavia, Mongolia, Russia, and Siberia. When food is scarce, some owls will irrupt southeast to the northern Midwestern and Northeastern regions of the United States. An irruption is an irregular migration to a location that is not normally part of a bird’s range, usually due to food scarcity.

Habitat: 

Boreal forest, also know as taiga, with a combination of mixed woods/conifers and openings such as sedge meadows and wetlands in lowland areas. Also fir and pine forest next to montane meadows (ecosystems with seasonally moist to waterlogged soil)

Diet:

Mainly small mammals, such as voles, pocket squirrels, mice, weasels, and other rodents. A small percentage of their diet is other birds. Great Gray Owls have terrific hearing and will mainly hunt by sound while sitting on a perch or gliding silently over the snow. Their large facial disks help them focus the sound, and they use their asymmetrical ears to locate the prey. They will plunge over a foot into snow to catch rodents. These owls mainly hunt at dusk and dawn.

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Great Gray Owl (Image via pinterest)

Breeding/Nesting:

Great Gray Owls do not build their own nests, they use abandoned raptor or corvid nests. They generally choose a nest near an open bog or meadow. Pairs are monogamous during breeding season. Males will feed the female as a courtship behavior and the pair will allopreen (preen each other). 

Snow depth seems to determine when a female will lay eggs. Depending on the region egg laying can take place anywhere between mid-March and late May. Females will start incubating the eggs after the first one is laid. A brood may have between 2-5 eggs. After 28-36 days of incubation by the female, the eggs will hatch. The male will supply the food while the female feeds the young for about 3 weeks. At that point, the owlets may start to slowly venture from the nest. The female will usually abandon them to be taken care of by the male after they owlets fledge. Great Gray Owls generally have 1 brood, but may breed multiple times if prey is abundant.

Vocalizations:

Deep, powerful whoos that may be repeated up to 10 times and descend in pitch towards the end. Females are higher-pitched than the males. A bi-syllabic contact call: doo-it doo-it. 

Conservation/Status:

Due to their elusive nature, it’s difficult for ornithologists to get a clear number on population. Estimates are around 31,000 individuals in North America. They are considered “vulnerable” in some areas. The greatest threat to Great Gray Owls is timber harvest, and land management programs are in place to protect their habitat. It’s unclear how climate change and its effect on rodent populations will impact Great Gray Owls.

Fun Facts:

  • Most of the year these owls are nocturnal, but they tend to be more diurnal in the summer and midwinter. Some scientist believe their proportionally small eye-size contributes to a partially-diurnal lifestyle.
  • Great Gray Owls tend to be less aggressive than other raptors in general, but will fiercely defend their nests and young. They are also one of the few owls that have been documented in performing distraction displays to lure intruders away.
  • The Great Gray Owl is the provincial bird of Manitoba.
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By Arne List (http://www.flickr.com/photos/arne-list/2363789109/) [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)%5D, via Wikimedia Commons

Burrowing Owl Wednesday

This week for Owl Wednesday I chose the Burrowing Owl. Why? Just Google “Burrowing Owl” and look at the images. Cuteness abounds. You won’t be disappointed. 🙂

Burrowing Owl (Athene cunicularia)

Description: 

Burrowing Owls are small owls (about blue jay-sized) with long legs and short tails. These brown and white birds are mottled/spotted on their underparts and horizontally barred on their upper parts. Their facial disk features a prominent white eyebrow and a white lower margin below the bill. Burrowing Owls have bright yellow eyes, but some juveniles in the Florida population have olive or brown eyes that may transition to a gold color with brown spots. Burrowing Owls are the only North American owls that are non-reversed size dimorphic. This means they are the only owl species where the males are larger than the females in measurement. These owls are also unique because they are diurnal (active during the day), although they can be nocturnal as well.

Range:

Western population north to south from Canada to Arizona/New Mexico and west to east from California through the Midwestern states are migratory/partially migratory. They winter in Texas, parts of Central America, and South America. Populations in the Southwest, the northern part of Central America, Florida, and the Caribbean are residents.

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By travelwayoflife (Flickr: Owl Family Portrait) [CC BY-SA 2.0 (https://creativecommons.org/licenses/by-sa/2.0)%5D, via Wikimedia Commons
Habitat:

Open places, such as prairie lands, range lands, deserts, coastlines, open scrubland, golf course, sage brush, pastures, road sides, agricultural fields, vacant lots, housing developments. They are usually found with prairie dog towns of the West, but have become closely  associated with humans due to habitat loss.

Diet:

Mainly insects. Rodents, small birds, lizards, snakes, beetles, grasshoppers. Sometimes jackrabbits, cottontails, and young prairie dogs. They catch prey with their talons by walking, running, flying, and hovering. They hunt most actively at dusk and dawn.

Breeding/Nesting:

As their name suggests, Burrowing Owls nest in burrows underground. They are the only owl in the world to consistently do so. These owls are semi-colonial, so they can be found nesting closely in small groups. Many owls in the Western population depend on existing burrows from prairie dogs, ground squirrels, armadillos, and other ground-nesting mammals. However, there are not many large burrowing animals in the Florida population, so they tend to excavate their own nests.

Burrowing Owls have 1 brood per year, with a clutch size of typically between 4-9 eggs. Some females will begin to incubate once they lay their first egg, but some Canadian females wait until half the clutch is laid. Eggs are incubated for about a month and owlets will come above ground starting at around 2 weeks. The young fledge at about 6-7 weeks old. Burrowing Owls will return to their breeding grounds between mid-March through May, and owlets tend to disperse in late summer.

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Burrowing Owl Family (Image by animalspot.net/burrowing-owl.html)

Vocalizations:

2 or 3 note wa-WAAH-oo by male. Females respond with eep!. Famous for “rattlesnake rasp” given by nesting females and owlet, which makes these birds sound almost exactly like a rattlesnake. Alarm chatter is WEEt-whit-whit-whit with typically 5-7 sharp notes.

Status/Conservation:

Populations have decreased over time. Listed as endangered in Canada, and although not listed under the Endangered Species Act, considered endangered in 15 of the 19 states where they live. Threats include habitat loss, prairie dog/ground squirrel control programs, agricultural practices, pesticides, and collisions with vehicles.  Artificial nesting sites, protective legislation, and habitat preservation programs have all aided Burrowing Owls to recover in some areas.

Fun Facts:

  • Burrowing Owls will line the entrance of their burrows  with dry manure. Some scientist believe dung is used to attract beetles and other insects for food, while others think its to mask their scent to mammals. However, they will line their burrows with other items such as corn cobs, pieces of bone, feathers, metal foil, bottle caps, and other man-made trash.
  • The species name, cunicularia, derives from the Latin word cunicularius, meaning “burrower” or “miner”.
  • DNA microsatellite analysis shows that there are many genetic differences between the Western and Florida subspecies. The evidence from this study suggests that these species diverged approximately 350,000 years ago.
  • All other small owls have vertical breast markings, while Burrowing Owls have horizontal barring.
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Burrowing Owls (Image from vk.com via Gary Nealy Jr./Pinterest)

 

Owl Wednesday!: Barn Owl

Guess what, friends? The weekly featured bird profiles are returning!

I used to write a weekly bird profile column, each season about a different family (such as Migration Monday, Waterfowl Wednesday, etc, links are to the right on this page). I stopped these in the spring (not intentionally, things just got super busy!), but now they’re back. This autumn’s featured family: Owls!

I was inspired to do an autumn owl feature for two reasons: 1. I just love owls and 2. Dave bought me the Peterson Reference Guide to Owls of North America and the Caribbean by Scott Weidensaul for my birthday. He also bought me Hummingbirds: A Life-size Guide to Every Species by Fogden, Taylor, and Williamson, but we’ll save that for another season. (Fun fact: owls are more closely related to hummingbirds than they are hawks/falcons). I also recently purchased this lovely Barn Owl print by David Kiehm of Dead Studio. So without further ado, let’s talk about Barn Owls!

Barn Owl (Tyto alba)

Description:

Barn Owls are one the most distinctive owls in the world. Their heart-shaped faces and pale bodies give them a ghost-like appearance as they silently fly through the night. Barn Owls have long legs and round wings combined with short tails. Their heads and upperparts are a tawny brown while their underparts are pale and mottled. Males and females look similar, but females tend to be more heavily spotted. They have large black eyes and lack ear tufts. Barn Owls have a pectinate middle claw; a modified comb-like talon mainly used for preening and parasite control.

Barn Owl chicks go through  two downs coats. A white natal coat is later replaced by a thicker gray coat. It takes about three molt cycles for young owlets to replace all their juvenal flight feathers.

6-6 we're ready for our closeup!
Young Barn Owlets at various development stages (Screen shot taken by BirdNation from Cornell Lab’s Barn Owl cam)

Range:

Barn Owls are the most widespread raptors found on the planet. They can be found all across the continental United States, Mexico, and South America. They also live in the Middle East, Europe, and Africa.

Habitat:

Open land; grasslands, marshes, fields, open woodlands, farms, prairies, and desert. Generally avoids dense forests.

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Barn Owl (Image via Pinterest.com)

Diet:

90% rodents. Rat, voles, mice, shrews, lemming, rabbits, and bats are common prey items. Occasionally eats birds. Barn Owls swallow their prey whole and cough up pellets  twice a day with undigested materials. While nesting, they will cache prey items for later use. A nocturnal hunter that tends to stay low to the ground and moves slowly.

Breeding/Nesting: 

Barn Owls are generally monogamous and mate for life (although polygamy has been observed sometimes). Males will attract females by doing flight displays, and when a nest location is selected, will bring prey to the female. Barn Owls nest in cavities and will use artificial nest boxes. The female will line the nest with shredded regurgitated pellets before laying 3-8 eggs (but usually 4-6). A new egg is laid every 2-3 days. This means that chicks will hatch 2-3 days apart putting the older owlets at an advantage. Eggs are incubated between 29-34 days, with young fledging about 50-60 days post-hatch.

The mortality rate of Barn Owls in fairly high. Competition for food among 4-6 owlets is fierce, and often times younger chicks will not survive if food sources are scarce. It is possible however that the younger owlets can survive if prey is abundant. Barn Owls can have up to 3 possibly broods per year and can breed at any point during the year, even in their Northern-most range.

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Female (left) and male (right) owls in nest box (Screen shot taken by BirdNation from Cornell Lab’s Barn Owl cam)

Vocalizations:

Hair-raising, high-pitched screams, hisses, and screeches. Can have between 4-15 different vocalizations

Status/Conservation:

Populations are hard to track, but may have slightly increased in some areas and listed as a “special-concern” species in other areas. Sensitive in changes to agricultural practices, suburban/urban development, and pesticides. Often struck by cars. Nest boxes have helped numbers improve in many areas.

Fun Facts:

  • Barn Owls are the only species in the family Tytonidae, while the other North American owls are in the family Strigidae. There are 46 races of Barn Owls worldwide. The North American race Tyto alba pratincola is the largest, while the Galapagos Island race is the smallest.
  • Barn Owls, unlike many other birds, will roost in their cavities all year, not just during breeding season.
  • Barn Owls have excellent hearing to help aid in hunting, but also have great low-light vision.
  • Barn Owl mates form strong pair-bonds. They will often call to one another, allopreen (preen each other), and link beaks to strengthen their bond.
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Pair-bonding (Screen shot taken by BirdNation from Cornell Lab’s Barn Owl cam)