Happy #SuperbOwl Sunday! I spent a decade studying #owls for my masters and Ph.D. In that time, I've accumulated a lot of interesting facts about our favourite feathered friends. I thought I might take this opportunity to share some. 🧵1/ *all images mine unless otherwise noted.
There are 243 species in the order Strigiformes (owls and barn-owls) divided into 2 families. Here in Manitoba, we have ten species (all in family Strigidae), though burrowing owls are starting to get a foothold again (which is mess up my poster 😉) 2/ #SuperbOwl
The great gray owl (Strix nebulosa) is the largest owl in North America by size. They have a wingspan of about five feet, but they're not the heaviest (they only weigh about 1 kg - 2.2 lbs). Snowy owls can weigh up to 4 lbs. In most species females are larger. #SuperbOwl 3/
Here in North America, most owls hunt at night, or are crepuscular (hunting at dawn and dusk). Snowy owls and northern hawk-owls are exceptions. Other species, like great grays, become more active during the day in the winter. 4/ #SuperbOwl
Owls have very large tube-shaped eyes to allow for large corneas to let light in. If we had similar-sized eyes, they would be the size of dinner plates. Their retinas have way more rods than cones, so they have excellent night vision at the expense of colour vision. #SuperbOwl 5/
These eyes, like those of all birds, are fixed in their sockets. They can't move them from side-to-side like we can, so instead they turn their heads. They can rotate their heads 270 degrees to look right over their back. #SuperbOwl 5/
Many owls also use sound to locate prey and have asymmetrical ear openings. Sound hits each ear at a slightly different time. Their brain can process differences of 1/10,000th of a second an use it to pinpoint prey in the dark or under snow. #SuperbOwl 6/
The ears are helped by large discs of stiff feathers that can take up much of the face. This works like cupping your hands behind your ears, funneling sound into the openings. Great gray owls can hear prey under a foot of snow! 7/ #SuperbOwl
Because sound is so important to both them and their prey, owls are silent fliers. This is thanks to tiny serrations on the leading edge of their wing feathers that break up the air into tiny eddies, muffling the sound. 8/ #SuperbOwl
Owls have sharp talons and zygodactyl feet - two toes in front and two in back. However, they can swing one back toe forward, if-needed. Great grays have long legs and can punch through snow crusts strong enough to hold up an adult man! #SuperbOwl 9/
Owls don't built their own nest. Large owls, like great grays, great horneds, and long-eared lay their eggs in abandoned stick nests, but will also use platforms, and like this one great-horned, a duck tunnel! 10/ #SuperbOwl
Smaller owls, like screech-owls, northern saw-whet, boreal owls, and the larger barred owl, nest in tree cavities, but will also happily take nest boxes. It's this use of nest boxes that made my research on saw-whet owls possible. 11/ #SuperbOwl
Depending on the species, owls can lay between 2 and 8 or 9 eggs. The average for the saw-whets I worked with was 5-6. They lay one egg every 2 days and start incubating after the second one. 12/ #SuperbOwl
You end up with young of different ages in the same nest. The oldest can be 2 weeks older than the youngest and at different developmental stages. It's insurance: in good years all will make it. In bad, the youngest will die, but they don't lose the whole brood. #SuperbOwl 13/
Owls are fascinating birds and a critical part of their ecosystems. The engender a lot of awe and excitement when people are lucky enough to encounter these often elusive birds. 13/14 #SuperbOwl
They're also sensitive to disturbance like habitat loss and overzealous naturalists/photographers. Many of these images were taken during the course of permitted research and all with the owl's welfare in mind. Always give them space and let them stay wild. #SuperbOwl 14/14

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More from @SecondNatureMB

Dec 23, 2022
With so many people in North America experiencing cold they're not used to, I thought it might be a good time to look at how wildlife handles snow and cold in places like here in Manitoba where these temperatures are the norm. 1/ Looking out over a frozen lakeshore. All of the trees and ro
Although many insects die in the winter, leaving their eggs behind to hatch in the spring, some do hibernate. These overwintering insects break down glycogen that they accumulated from their diet into glycerol that acts as an antifreeze in their blood and tissues. A bulge in a goldenrod stalk is a gall where a goldenrod galA spotted tussock moth caterpillar. This black and yellow stA brown butterfly with pale yellow wing edges is a mourning
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About a month ago, I watched a little red-backed vole dash into this hole in an old downed aspen tree in my backyard. It was clear that it was living there, so I set up my trail camera to catch a glimpse of the wildlife using this log. #cameratrap 1/ 🧵
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Feb 3, 2022
I get a lot of questions about how our wildlife can survive the cold. It can be -35C and you'll still hear and see signs of animals everywhere. How do they do it? I thought it might be fun to take a look at some of our wildlife's amazing adaptations for winter. #scicomm 1/
Losing heat, especially from the core, is their biggest problem. We just put on more clothes and in some ways, animals do too. Chickadees have 50% more feathers in the winter. Mammals grow thicker fur, with longer guard hairs that trap warm air near the body. 2/
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Happy #WorldWetlandsDay! Wetlands are critical to the well-being of the planet. I've been lucky to have had many opportunities to share the stories of wetlands through interpretive signage and thought it might be fun to look back on a few. #sciart #scicomm 1/
I often find myself answering the question 'What good are wetlands?' Once considered wasteland by farmers and developers, we're finally understanding the important ecological services they provide. #WorldWetlandsDay #sciart #scicomm 2/
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May 12, 2020
I was asked if I could outline the steps I go through to create a panel like this. It's a long process and I'm lucky to have the skills and training to do all of the pieces: content writing/research, illustration & layout, so I thought I'd walk you through it. 1/ #scicomm #sciart
It starts with a concept sketch. The client and I discussed the story they wanted to tell and the looks we liked and I scribbled it into my sketchbook. Species were chosen from the garden plants this panel was for and I researched their associated pollinators. 2/ #sciart #scicomm
Once I have an general idea of what images I need, I start drawing. I have a huge reference photo library, but will sometimes ask for permission from other photographers to use their images as references. 3/ #scicomm #sciart
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