By VAL CUNNINGHAM

Q I feed peanuts in the shell to the back-yard squirrels and birds and have noticed the blue jays doing something odd with them. They'll pick one up, lay it down, pick up another and then drop it in favor of a third peanut, before flying off. Any ideas about what they're doing?

A This behavior points up how smart blue jays are. They want the biggest reward first, so they're picking up each peanut, looking for the heaviest one. Once they have a heavy peanut in the beak, they fly off to consume it or hide it for a later snack. Then they return to find the next heaviest nut, and so on. Blue jays can clear out a pile of peanuts very quickly. This is pretty amazing bird behavior, and it may be even more amazing that researchers have studied jays to come up with the answer.

So many crowsQ The sight of all those crows heading toward downtown for the night fascinates me. Does this mean that crows have recovered from West Nile Virus? When they head out for the day, what do they eat?

A I asked Kevin McGowan, a researcher at the Cornell Lab of Ornithology, about crow roosts and he notes that we can't tell much about the health of crow populations by the size of a nighttime gathering. The roosts we see may be drawing in all the crows around our area. Midwest crows were hit harder than crows in any other area by the nearly always fatal virus and no one knows whether the population is recovering yet. When they head out during the day, they're looking for what omnivores eat, anything and everything. Crows eat roadkill, but they also check compost heaps, lake ice for fishsicles, farm fields, bird feeding stations, crabapple trees and so on.

Birds for kidsQ Our little granddaughter, who loves watching birds, is coming for a visit and I want to make sure there are birds to see. Any suggestions?

A It's wonderful that you're introducing your granddaughter to the fascinating world of birds. In this extremely cold winter, birds have sometimes seemed scarce. Try sweeping off a spot for ground-feeding birds, then toss some cracked corn and millet seed there each day. A suet feeder should bring in woodpeckers but is also popular with squirrels, so try hanging the feeder from a shepherd's hook pole.

If you have a deck or patio (or swept spot), it's fun to toss out 15 or so peanuts in the shell and watch the blue jays show up. They'll "weigh" each one, departing with the heaviest first, then return until they've carried them all away. A birdbath with heater is a reliable way to attract winter birds: Even if they can find food in the wild they're always thirsty for a drink.

Feeding without fearQ After seeing a Cooper's hawk swoop in and grab a bird, I'm wondering if I can build some kind of shelter for birds as they feed.

A Good question -- most of us are just trying to feed our back-yard birds, not feed them to predators. If you search on the Internet, you will find a variety of suggestions for building shelters for birds, from a kind of plywood teepee to a simple brush pile. A pile of branches and twigs does provide excellent shelter for birds in all kinds of weather and from most kinds of predators.

Another way to protect ground-feeding birds, a category that includes cardinals, mourning doves, sparrows and juncos, is to place chicken wire around the base of an evergreen tree or shrub. Toss seed inside the wire and birds feed happily and safely inside. I saw a kestrel once slam into such fencing around a pine tree, with no injury to itself and he was not able to snag a sparrow feeding inside.

Hawk or owl?Q Could a red-tailed hawk kill a cottontail rabbit? We found a rabbit carcass in our yard, with no tracks around it, and wondered what animal did this.

A A carcass with no tracks around it does sound like it was killed by a bird of prey. Red-tail hawks can and do capture and kill rabbits, but so do great-horned owls. Hawks work the day shift, owls hunt at night. So if you found the carcass in the morning and it hadn't been there before, I'd vote for an owl as the predator. If the rabbit remains showed up sometime during the day, then it might have been a hawk's prey.

Pileated woodpecker makes urban visitQ A large bird landed in a tree near where I was walking, and I realized it was a woodpecker, the largest I've ever seen. When I looked it up in a bird book I found it was a pileated woodpecker. I live in the city and wonder if it's unusual to see these birds here, and will it come back?

A These large (crow-sized) woodpeckers patterned in black, white and red are always an awesome sight. It's not usual to see them in an urban area but they're not a rare sight, either. Pileateds have fairly large feeding territories, which include ample woodlands. They range through their territory, stopping to search for insects hidden in old or dead trees. Sometimes you'll hear the pileated's wacky, high-pitched call before you spot one. This website has a recording of their call: www.allaboutbirds.org/guide/pileated_woodpecker/id.

Val Cunningham, a St. Paul nature writer, bird surveyor and field trip leader, can be reached at valwrites@comcast.net.