Let it Snowl, Let it Snowl, Let it Snowl!
Imagine if you unexpectedly came upon a Polar Bear, an Arctic Fox or a Snowy Owl casually moseying down your street. One might assume it’s also the day when the sun decides to remain under the horizon! But, the sun came out, and a female Snowy Owl, found herself nestled cosily on the ledge of The Washington Post building (fortuitously, a few floors down from the Capital Weather Gang’s workspace) in DC. But sadly, her fate was sealed! She was hit by a bus, and is now being cared for at the zoo.
Birds don’t usually draw the same brouhaha as animals! Hedwig may be more popular than Iorek, but in the human circles, Polar bears outclass Snowies all the time. No one made a fuss about Hedwig being played by male Snowy Owls in the movie because Harry “Daniel Radcliffe” Potter can’t handle a heavy female. The popularity of animals over birds has nothing to do with their beauty, rareness, fearsomeness or intelligence. This is how we have come to size things up. But, this year the Snowies are attracting a deluge of onlookers, because of the unlikely places they are being sighted in.
Snowy Owls are one of very few avian species who have the audacity to wait out the winter season in the Arctic. It is usually the full grown adults wanting to breed that stick around in these unmerciful areas. The Snowies that choose to skip the breeding season, and the young ones who are less equipped to survive up there, fly southward where the weather is less extreme. Still, it nearly never happens that south-flying Snowies fly all the way to the Mid-Atlantic, and as far south as Florida, as we witnessed this year. One curious Snowy even made it all the way to Bermuda!
For years, scientists cerebrated over these on and off massive irruptions, and have not been able to make sense of them. In order to do a systematic study of Snowies, scientists need to understand how the owl’s live in their main domicile, as well as what motivates them to travel to places with extremely different ecologies, especially since they don’t migrate every year but sporadically, and for a limited amount of time. The hypothermic weather in the Arctic makes observing the owls there impracticable. Added to that, Snowies are extremely nomadic even in the Tundra. They not only follow the cyclical nature of lemmings, that are abundant one year and scare another, and move around a lot, but also go after bigger lemmings, and therefore an abundant population of those that breed less! So scientists have been limited to compiling information about the the owls that migrate to the south, where are more easily observable, and have been doing so since the early 19th century!
What they’ve found so far is that Snowies are both individualistic and collectivistic. Every owl follows a different trajectory of living, hunting and breeding, making it difficult to make broad generalizations about the species. At the same time, they also choose to travel in boids (loose groups), so that one’s fate is tied to another’s. It seems as if being a part of a boid to them is a choice and not a given, making boids fundamentally different from flocks.
The magic of the Snowy Owl is not in how they survive in a pitiless landscape, but how they transform themselves physically, and make the impossible possible. But, magicians never reveal their secrets, not even if you put them under a knife. If you saw them in half, they won’t tell you anything at all, and you won’t be able to put them back together, because you are not a magician. I consciously share this analogy to underscore a sad piece of information that I learnt from the Snowy Owl book. Up until the 1940s (and perhaps even later), biologists who wanted to understand the diet of Snowy Owls would cut them open to examine their stomachs’ contents. One particular scientist examined 205 stomachs, meaning 205 Snowy Owls were killed; 78 of them had empty stomachs, which means they were cheated out of life for nothing! This is in spite of the fact that one scientist in the 1930s made popular how owls’ regurgitated pellets could be used to understand their diets, so that owls don’t have to be autopsied to understand their diets! Snowy Owls are one of the most delicate bone digesters in the world. They preserve more bones of prey in their pellets than most other birds and make ‘little’ modification to the bones in their pellets.
Pellet analysis can reveal not only what an Owl ate, but also how many species and the size and weight of each! Moreover, Pellets of owls take as much as 10 years to decompose, because of the cold weather in their chosen habitats, so the information is in tact for a long time! In fact, the Owl too routinely tastes its chicks’ pellets to assess their wellbeing and hunger levels. For instance, the absence of bones in the chicks’ pellets would mean the chicks didn’t get enough food, so the digestion sucked every last calorie from their meal. Fortunately, today, scientists don’t cut open Snowy Owls! They capture, examine, band and release them!
This year Snowies migrated southward is unusually high numbers! This kind of irruption hasn’t been seen in may never happen again (even though a long-term look at irruption patterns point to more and more Snowies migrating over the years!). Over two dozen researchers, including the Pulitzer nominated author Scott Weidensaul have come together to work on Project Snowstorm to understand this anomaly, and other physical and behavioral characteristics of the owl! They are using new methods of tracking the birds, such as solar-powered GPS-GSM transmitters, and also performing DNA and feather analyses, among other things.
The transmitters weigh 40 grams, which is the size of one lemming, and about 1.5-3% of the owl’s weight. This makes me uncomfortable, as owls determine what they eat and what they feed their chicks based on the weight of the hunted prey and their energy budget! The transmitters that are attached to their wings using a backpack harness should make flying inconvenient and cost them some energy on top of their usual expenditure.
That being said, scientists are already recording many differences in hunting strategies and invalidating many commonly held notions about their migratory motivations and their movements. One such myth is that the Snowies are here due to a shortage of lemmings in the Arctic. In fact, the abundance of lemmings in summer, led to a successful breeding season, and the current bumper crop of Snowies!
It has been believed for a few years now, that the mass irruption is the result of complex stochastic processes having to do with the availability of prey, winter snow thickness, but more importantly, the relationship between individual owls in their boids. Snowy Owls tend to travel to wintering grounds and breeding grounds in groups. It’s a loose structure where individuals keep safe distance from each other while also monitoring each others movements to get to places with rich food sources. Sometimes, this strategy works very well, and they hit a lemming bonanza, and pair up and start breeding. But, in some other years, they find themselves in an infertile area deficient in lemmings or alternate prey, but are too weak to move elsewhere and leads to mass deaths!
Snowies' most-preferred urban habitats are airports, because they offer vast open spaces with few trees and limited human access, and noise pollution. The noise factor gives the Snowies an advantage over other owls that use their ears and hunt in the dark close to dawn and dusk! Even though the Snowy Owls are diurnal, in the airports, they become very active when the sun begins to set. Here, they capture everything from tiny insects to large raptors, and even the Great Blue Heron and other Snowy Owls. While some airport owls are very healthy, others, especially the adults are exhausted and underweight.
Some years there are as many as fifty owls in one airport, which makes them all the more susceptible to being hit by planes. FAA recorded over 120,000 wildlife strikes (the vast majority were birds) in a 10-year period, and 11,000 strikes last year alone. Bird strikes have caused up to $700 million a year damage to civilian and military aircraft. At least five snowy owls were hit by planes in the US this winter season! A few States have “shoot-to-kill” orders, but most prefer to trap and relocate them.
But, in the early 1980s, research of 385 owls at Logan Airport revealed that the presence of owls in airports discourage flocking birds from roosting in the area. And attempting to disperse the owls only created a greater risk of a bird strike than just leaving them alone.
I recently watched the Magic of the Snowy Owl, which documents the life of one Snowy Owl pair raising their young in a very bleak part of the Alaska North Slope, where food seems scarce and there is little relief from cold winds, rainstorms and freezing fogs. It’s a story of struggle and triumph with all the deflating and elevating elements of reality-melodrama. There is this sense that you are furtively observing The Addams Family of Snowy Owls. The narrator suggests that everything the family are doing is unusual and never been recorded before; like one kawaii scene of owlets daring to cross the river. It was the first time that this behavior was ever recorded or filmed.
In reality, a lot of what the movie thinks is unusual has in fact been observed many times before. The Snowy Owl book by Eugene Potapov and Richard Sale that I mention a few times in this post, provides both scientific and anecdotal evidence from all over the world to this effect. If you’ve enjoyed the movie, I recommend the book to contemplate the bird’s stunning and peculiar ways and facets.
In a different post, I share insights from the book, and clarify some of what the movie thinks is unusual. But mainly, I intend to share how the owl magically transforms itself physically and does amazing non-birdlike things; such as how it changes its spots, manipulates the sex-ratio of its offspring, and enjoys recreational sex, among other things!