Snowy owls usually live in the Arctic tundra, but every so often they'll head south in extraordinary numbers.
This invasion is referred to as an "irruption," and this past winter has marked one of the biggest in decades.
They've mostly flooded the Northwest and Great Lakes region, but some have even flown as far as Florida and Bermuda!
Shocking, I know!
Mega-irruptions can happen once or twice in a lifetime, so researchers have started tagging and tracking owls to learn more about their mysterious lifestyle.
Project SNOWstorm researchers attach GPS transmitters to the owls to track them in real time. (SNOW is the four-letter code that birders use for the snowy owl.)
These harmless trackers don't hurt the owls or influence their behavior in any way, so researchers can watch their natural activity.
Researchers hope the transmitters will reveal more about the birds' ecology and physiology...
...like where they came from and the threats they face during an irruption.
That way they can help conservation efforts.
The devices transmit signals one to two times a day and can store up to 100,000 locations.
This map shows snowy owl sightings for November and December 2013. You can see the live tracking on eBird's map.
Snowies subsist mainly on lemmings, and plentiful food during their summer breeding season might contribute to mass flights.
That's because high populations of lemmings and other small prey leads to large clutches of owl eggs.
Now these young, healthy snowies have ventured out of the nest and moved south.
