What do you feed boreal owls recovering from winter misadventures here?
That's the kind of question answered at the Raptor Center at the University of Minnesota campus in St. Paul after an influx of boreal owls moved south from their Canadian homes. This tiny polar owl has been seen in northern Minnesota in unusual numbers over the past three months.
Two are at the Raptor Center. One was delivered with an injured eye, the other undernourished.
So what do you feed them? Mice and day-old chicks — dead, frozen, thawed and chopped. In limited quantities, two mice and one chick per day.
The owls are getting the nourishment they need for recovery and eventual release. They aren't fed all they might eat, however, because they tend to get fat. No, really — owls can get fat.
They'll eat as much as they're given because in the wild, birds eat as much as they can whenever they can, given that the next meal is unpredictable.
The owls' main dish in the wild is a red-backed vole. At this point in my interview with Lori Arent, Raptor Center clinic manager, I asked what I considered to be a dumb but necessary question: Since the owls take much of their prey from beneath snow cover, and since they locate prey by sound, do red-backed voles somehow sound different from other small rodents?
No (just as I thought!). These voles sound like other voles or mice or shrews. And if the catch isn't the preferred species, the owl does not say sorry and move on. Caught is synonymous with eaten.
I didn't ask why the boreal owls consider red-backed vole a favorite. Think about it: What possible difference could there be in small rodents? Every living thing has its job, however. Somebody has to do voles.
In mid-February birders routinely saw as many as seven boreal owls a day along Old Hwy. 61 between Duluth and Two Harbors. Mike Hendrickson, who guides birders in the Duluth area, told me that maybe 40 or 50 individual owls had been reported in the past several weeks. That might not sound exactly like Broadway, but for this species here that's Big Time.
Consider, though, the unknown. How many of these little fellows were here but not seen, the sightings not recorded? Hundreds or thousands could be back in the woods, hunting on thousands of square miles of suitable Minnesota habitat.
Remember 2005 when great gray owls came south into Minnesota by the hundreds? You could see dozens in a day if you drove the right roads. Thousands of great grays were seen, but again how many were not seen?
Boreal owl reports declined in late February as the birds moved on. Some died; dead owls were found here and there, two as far south as Sherburne County.
Starvation is the likely cause of those deaths. It's young birds that come south to find food, unable to compete with adult birds at home. Juvenile hunting skills are a work in progress. The birds come to an area not quite familiar. Crusty snow has made hunting difficult.
And some of them go to the hospital, where, just like for you or me, someone is making certain nobody eats too much.
Lifelong birder Jim Williams can be reached at firstname.lastname@example.org. Join his conversation about birds at www.startribune.com/wingnut.