“There’s a snowy owl along Highway 71, just north of Spirit Lake.”
It seems that plenty of people have gotten to experience the excitement of seeing the largest owl, by weight, in North America. So far this winter, more than 160 snowy owl sightings have been reported to the Iowa Ornithological Union.
It seems rare to see this many snowy owls this far south, when usually Iowa only has 10 or so in the state, but the higher number this season is not all that uncommon. The populations of the owls grow in a cycle of every four to five years, and when populations boom there is not enough space in their southern migration grounds, so more end up traveling even farther south than usual to find food.
Snowy owls spend their summers in the Arctic hunting lemmings, ptarmigan and other prey in the 24-hour daylight. Their primary food source is lemmings, and these rodents have cyclical population patterns, spiking every five to 10 years. When their populations spike, the numbers of snowy owls rise as well.You can see in this range map that Iowa is a part of the snowy owl’s typical winter range, and they can often be found along shorelines, near agricultural fields and by airports.
Although snowy owls are not completely uncommon in the state they still are a majestic bird that gets people out taking pictures and traveling long distances to be able to see one.
So what makes these birds such a draw?
Probably the biggest draw to snowy owls is their bright, white feathers. Males tend to be whiter, while females will have more brown or black markings on their body and wings. Males will even become paler and whiter as they age.
Snowy owls are easier to spot than other owls because they are diurnal — meaning, of the day. They hunt during daylight hours, because in their breeding grounds in the Arctic it’s always daylight. In Iowa, that makes them easier to spot as they sit near the ground, looking for prey.
They will also stay in the same spot for a long time, often hours, as they look and listen for prey.
The snowy owl is also impressive because of its huge size. Adults typically weigh about 4 pounds, partially due to their thick feathers and fat that insulate them in the cold.
For reference, a great horned owl weighs about 3 pounds on average while a great gray owl — America’s tallest owl — weighs about 2 pounds.
Snowy owls are known as irruptive, appearing in some winters but not in others, and since they live in such remote areas and have huge territories it’s difficult for scientists to estimate their actual population size. Partners in Flight estimates a global breeding population of 200,000, with 24 percent wintering in the U.S.
Have you seen a snowy owl this winter? Let us know where and when!