It’s an invasion of historic proportions. While the term “invasion” has plenty of negative connotations, this one is making news all over the state in a positive way. It’s got people from all walks of life jumping in vehicles and heading to the country to catch a glimpse of these winter visitors. And if you ask nature enthusiasts and birders about the significance of this event it ranks right up there with the best of them.

“It’s best described as a ‘Northern owl’ invasion,” said Dr. David Seibel, biology professor at Johnson County Community College who has his Ph.D. in Ornithology. “When snowy owls come down into the United States, other owls like great gray owls and northern hawk owls come down, too.”

But it’s the snowy owl that’s creating quite a stir in the Sunflower State right now. More than 70 sightings have been confirmed with countless others likely yet observed.

“Most years we get one or two reports of snowy owls in Kansas,” Seibel said. “But we’re approaching the maximum number we’ve ever observed.”

While their presence may not sound like a big deal to some, consider where they come from. Snowy owls are at home on the tundra of the Arctic and Sub-Arctic and Alaska. The distance from these reaches is more than 3,000 miles. So why are they here?

“Basically, it’s food,” Seibel said. “They feed on several species of lemmings and these animals have dramatic population swings that often crash.”

Snowy owls are large and bulky, mostly white with a few specks of dark brown or gray standing about 2 feet tall. They’re striking birds that weight about 3½ pounds but look much larger due to a 5-foot wingspan. Female snowy owls, like many birds of prey, are larger than their male counterparts. Snowy owls are the largest of the North American owls.

Unlike their nocturnal relatives, snowy owls are active by day. It’s no surprise as daylight is almost continuous within the Arctic Circle during the summer nesting season.

Snowy owls in poor years may not nest or lay only a few eggs. However, in good years with lots of lemmings individual nests may contain up to 14 eggs with an average clutch of seven to 10 eggs.

Eggs are laid in a shallow depression scraped in the tundra by the female lined only with a few feathers and pieces of grass or moss. The female lays consecutive eggs anywhere from a few hours apart to several days. As a rule, the last egg is laid about 15-16 days after the first.

The female snowy owl begins incubation as soon as the first egg is laid. The resulting nest of young will have chicks of various sizes, reflecting staggered incubation and the eggs will hatch in just over a month. Chicks may leave the nest when only two or three weeks old and the male snowy owl takes care of them. The young owlets aren’t able to fly until they reach about 8 weeks of age.

After a successful nesting season there is a big demand for food. In their home territory snowy owls eat arctic hares and ptarmigans, but their main food source is the lemming. A lemming resembles a small field mouse and they’re prolific enough their populations get huge quickly and destroy their available food. During these times lemmings die of starvation and disease in huge numbers.

It’s during these lemming crashes when southern Canada and the northern and central United States see the biggest influx of snowy owls. Many that venture down into the United States are young birds.

“This year we’ve got a statewide distribution of reports,” Seibel said.

In Kansas, many snowy owls take up residence near reservoirs. They seem comfortable around big water and the openness of the surroundings allows them to see a long way. The rocky rip-rap along the face of the dams are common hangouts and apparently remind them of the rocky outcroppings where they were raised.

Snowy owls in Kansas often stay in the same area and are visible for quite some time. They can be seen perching on fence posts or other high vantage points remaining motionless watching for food. In Kansas these birds prey on small rodents and birds and they’re fairly opportunistic.

Snowy owl adults have few natural predators in their Arctic abode, but the eggs and nest are predated by a number of other animals and birds. In Kansas, they have other worries as snowy owls aren’t used to man-made structures like power lines and vehicles. As a result, several have died after collisions with both.

Several birds have been reported outside Topeka and up to three have been seen at Clinton Reservoir. They are easily identified and many Kansans have spent hours searching to catch a glimpse or photograph one.

Seibel, a well-known freelance photographer, enjoys their presence and despite having snowy owl photos in his files he won’t pass up opportunities to get more or even better ones.

“Normally, they’re hard to photograph,” he said. “But now dozens of people are getting pretty good photographs and I still find it exciting.”

Seibel also offers up some photography and bird watching etiquette tips.

“You don’t want to harass the birds,” he said. “But some are very approachable while others aren’t.”

And according to Seibel there’s still time to mark it off your birding list if you haven’t seen one yet.

“I imagine many of them will be here another two or three months,” he said. “If they survive they’ll head back by early March.”

Marc Murrell can be reached

at mmoutdoors@cox.net.