Q: Since I was seeing robins in January, it wasn't such a thrill to see some in mid-March. If they're around all winter, what bird can we use as a sign of spring?

A: You're right, some robins remain in our area all winter and survive just fine on dried berries and whatever water they can find. They have a reliable way of signaling that spring is near, however: When you hear their sweet, loud melody in March, you'll know that males are beginning to establish their territories.

Feeding style

Q: Blue jays gulp quantities of sunflower seeds at my feeders, and then fly off. I'm wondering if they swallow the seeds whole and rely on their gizzards to grind them up, or if they peck each seed open and discard the hulls.

A: That's an excellent question, and because these big, handsome birds are so secretive, few of us are ever lucky enough to see them eat. Blue jays gulp a lot of seed and store it in their throat pouch, but they don't swallow seeds whole. Instead, they carry them off, either to hide for later or to peck open one by one, often standing with a seed between their toes and hacking with their beak.

Ugly duckling cardinals

Q: We watched cardinals raise their family in our backyard shrub last year, and I'm wondering when the youngsters develop that distinctive bright orange beak.

A: Young cardinals are "ugly ducklings," compared with their handsome parents, through their first six months or so. But as fall approaches, the young birds begin to drop their brownish feathers for adult plumage, and their beaks take on color. Both beaks and feathers gain color from the seeds and berries the birds eat after they leave the nest. By midwinter, most first-year cardinals look a great deal like their parents.

Pine nesters

Q: We have a pine tree in the backyard and wonder what birds might nest in it.

A: The American robin is the bird most likely to build a nest in an evergreen in early spring. They often build their first nest of the season on evergreen branches, since these provide shelter from the elements for nestlings at a time when deciduous branches are bare. For their second nest later in the season, robins generally choose a deciduous tree or shrub, or build under some kind of overhang on a house or garage. Blue jays also build their nests in evergreens, but later in the season.

Bad boxes?

Q: What do you think about these bluebird houses in the photos I've attached? They look a bit decrepit. You can see that they're nailed to trees.

A: The best thing to do with these nest boxes is to pull them down and use them for firewood. Woodpeckers or squirrels have enlarged the entrance holes, so it will be easy for unwanted birds, like starlings, to enter and take over the boxes. The boxes are in bad shape and will allow rain and cold to enter, thereby endangering the occupants. And boxes attached to trees are open invitations to squirrels, raccoons and many other creatures to reach in and pull out eggs and/or nestlings.

Providing housing for bluebirds and other cavity nesters is serious business and a very exacting enterprise. Please visit the North American Bluebird Society website for excellent information on helping without causing harm: nabluebird society.org

Note to readers

Now is a good time to give your backyard feeders a good going-over. If any have broken edges or sharp pieces of wood or plastic that might harm birds, please repair or replace them. It's also time to give each feeder a thorough cleaning (scrub away any droppings, swish through a bath of 1 part bleach to 9 parts water, rinse thoroughly, then dry them before refilling with bird food).

Check your stash of birdseed — unless it's been stored outdoors in the cold, it's probably time to replace the nyger and cracked corn and any sunflower seed that's becoming aged. One last thing: The ground beneath feeders is now full of debris and droppings that can sicken birds, so please rake this up and remove it. There, now you're ready to offer your best hospitality to your regular visitors and migrants just passing through.

St. Paul resident Val Cunningham, who volunteers with the St. Paul Audubon Society and writes about nature for local, regional and national newspapers and magazines, can be reached at valwrites@comcast.net.