There's no doubt that this has been a winter that few of us will soon forget.

It's been cold. It's been snowy. And if you've kept your eye to the sky, it's been a winter filled with an unusual sight.

Snowy owls have come to our region in surprisingly large numbers.

As of January, nearly half of Pennsylvania's 67 counties reported sightings of the regal birds. In fact, there's been a surge in sightings all across the mid-Atlantic region. Researchers and biologists are not quite sure why.

The ghost-like owls spend most of their time in the Arctic, where their bright white feathers help them blend into the scenery. The spend much of their time hunting rodents. But every once in a while — and scientists don't know why — they leave their traditional hunting grounds and head south.

These irregular migrations are called irruptions. Minor irruptions involving a small percentage of owls occur every few years. But this year is different. Scientists hail it as a once-in-a-lifetime event. It's the largest irruption the region has seen in more than four decades. Experts have dubbed it a "snow" storm.

Again, nobody knows quite why snow owls head south in such great numbers. It's not about food. There's plenty of food at home for the birds. And it's not about their health. The owls that have come to our region are healthy and, in many cases, fatter and larger than average.

With such good breeding conditions over the last couple of years, one leading theory hints that the irruption is a natural way of spreading the population. Juvenile snow owls are leaving their home grounds, expanding the boundaries of the species' territory.


Not knowing what causes the huge migration is why scientists have put so much energy into following the owls this winter. They're using GPS devices to track the movements of birds as they feed and move up and down the East Coast.

One of the owls that got close attention last month was named Philly. Scientists first began tracking the bright white owl in, you guessed it, Philadelphia. More specifically, it was tagged at the rodent-rich Philadelphia International Airport — where officials were worried about the bird "interacting" with the airplanes.

On Jan. 9, biologists captured Philly and relocated it to the heart of Lancaster County, where several other snow owls have found a safe temporary home. But Philly didn't like the new territory. In just a few days, it flew straight back to the airport, with its tracking device recording speeds of 35 mph along the way. Unfortunately, the owl was recently hit by a cargo plane and died — proving that our region requires a new set of survival skills.

Arctic-based snow owls certainly have not adapted to our environment. And they aren't a common site in southern Pennsylvania. But this winter, I'm convinced they feel right at home.

Hundreds of the iconic owls have made the often-deadly journey south. It's a once-in-a-lifetime treat for the region's bird watchers and yet another reminder that this winter has been like no other.

Andy Snyder writes about the outdoors for The York Dispatch. He can be reached at