Snowy owls graced our state in unheard-of numbers this winter. One of them will help researchers track the movements as these Arctic predators head north.
The magic will begin to end in March.
That’s when we can expect our snowy owl visitors to fly away north.
It’s been an exceptional visit, unprecedented, spectacular and well-followed. Certain owls, those faithful to a location, have received human visitors day after day. There has been national and local television coverage, radio stories and lots of print press.
For all of that, misunderstandings are common.
These owls, thousands of them from here to Maine, from Newfoundland to Virginia, came south for one reason. Not hunger. They needed space, according to Jean-Francois Therrien of the Department of Biology at Laval University in Quebec.
Therrien took a photo in northern Quebec in July. It showed a snowy owl nest rimmed with 70 dead lemmings. They had been brought to the nest by the male owl as the hen tended eggs.
I’m not certain that the hen owl was done laying when the photo was taken. She had but four eggs. When food is plentiful, snowy owls often hatch 10 or 12 young.
At that rate, 100 pairs of owls (200 birds) would in a few weeks increase by 1,000: 100 nests, 10 eggs per nest. There were hundreds, perhaps thousands of pairs of nesting snowy owls in the eastern Arctic. Do the math.
The birds simply did not have enough space to divide into hunting territories. Surplus birds were pushed south.
The birds will disperse as they return north, said Therrien, searching for places where lemmings are plentiful. The birds are not faithful to their hatching location. Owls raised in Quebec may well nest in Alaska or Greenland.
Lemmings sometimes exist in such large numbers that they eat themselves into starvation. They run out of food where they live beneath the snow, and die in numbers that mirror summer’s bounty.
This is not a problem that extends throughout the lemming universe. Lemmings are vigorous somewhere. If not, snowy owls eat ducks and small seabirds, rabbits and shorebirds. They will move onto the Arctic ice, scavenging polar bear leftovers. At least one owl is on record as having made a meal of a great blue heron.
If owls do not find sufficient food to feed a family, they will not breed.
Tracking their path
One Minnesota owl has been participating in a novel owl study called Project SNOWstorm.
As many as a dozen snowy owls scattered from here east have been tagged with tiny transmitters that broadcast location. Signals are collected every 30 minutes.
This is a long-hoped-for opportunity to learn about an animal that mostly spends its life in the essentially inaccessible Arctic.
Our owl is named Ramsey, after the city in which it is wintering. It was tagged Jan. 26. You can see a map showing Ramsey’s rather consistent movements in his small territory by going to www.projectsnowstorm.org.
Ramsey is a young male, hatched last summer. He was captured on site by Frank Nicoletti and David Alexander of the Hawk Ridge Bird Observatory in Duluth. They attached his transmitter, which rides lightly on his back and uses the sun for power.
The transmitter will work for years, sending signals to the project’s Philadelphia headquarters via cellphone networks. When the owl is not in cellphone range (or if his signal is dropped) the device will store signals for transmission whenever. It can store up to 100,000 location entries.
Researchers now will be able to see exactly where and when these nomads move.
If the owls remain available at this date, and if you visit them, be polite. Keep your distance. Don’t disturb the bird. Use binoculars or a spotting scope. Do not bait owls for photos. Absolutely do not feed the owls. Captured owls have been found to be fat and healthy, and don’t need human help. If they can’t find food, they will move.
When and if the owls will return here in such numbers is unknown. Weather changes in the Arctic are beginning to impact lemming populations, among other things. If the base of the food pyramid shrinks, no one is certain what that means for predators at the top.
Lifelong birder Jim Williams can be reached at firstname.lastname@example.org. Join his conversation about birds at www.startribune.com/wingnut.