Q: Our housing association recommends that birdseed be microwaved to prevent it from germinating. Do you know how long we should zap it and what setting we should use?

A: This question has been around for a long time, and there are a number of Internet sites that recommend baking or microwaving seed to prevent germination. However, bird experts don't seem to think it's a good idea. For one thing, heating the seed will pull out the oils, making a mess and causing the seed to be less nutritious for birds — they need the calories in the oil. In addition, some research indicates that baking at low temperatures won't eliminate the possibility of the seed sprouting. If seeds sprouting under feeders is a major concern, there are more effective things you can do.

For one, you could place pavers under the feeders to catch dropped seed and shells, then sweep or rake up this material on a regular basis. Or you could offer seed that has no possibility of sprouting, such as shelled pieces of sunflower seeds and shelled peanuts. These are an excellent food source for birds and are very popular with many species. The only drawback here is that rain can spoil these foods, since they lack a protective shell, so feeders should be shielded from the elements by a roof (or taken in when it rains).

Gosling day care

Q: Last year we had two pairs of Canada geese hanging out with their goslings on our pond. I'm wondering if they were sharing parenting responsibilities or just happened to like the same location.

A: You're right about Canada geese sharing gosling-minding duties. Sometimes several adults will keep a watchful eye on 10, 15 or even more youngsters, while their parents take a break. This kind of gathering is called a crèche by ornithologists, and is an amazing sight.

Tree swallow boxes

Q: I've built two dozen tree swallow nest boxes with perches and want to put them up soon. When should I do this?

A: You deserve a big pat on the back for creating housing for cavity nesters, since there are never enough holes in trees to go around. I hope you can take one more step, though, and that is to remove those perches. Tree swallows don't need them because they fly straight into a nest box without stopping, but perches tend to attract house sparrows. As you probably know, house sparrows compete fiercely for nest boxes and will even kill swallows to take over their space.

As soon as the boxes are "perchless," I'd set them out in likely habitat for your swallows. They prefer to be near water and open spaces so they can pursue flying insects. It's best if the entrance hole faces east or south, which will help keep the prevailing winds and rain out of the boxes.

Nesting materials

Q: I was given a decorative container that holds pieces of nesting material for birds to use. When should I put this out and where should I hang it?

A: That's a very timely question, since birds are nesting now. I'd hang the container from a tree branch at about the 5-foot level right now. This will give birds time to investigate this new thing and decide to give its contents a try. Robins and cardinals, especially, both of which raise two broods, might be happy to have some additional materials. If rain is in the forecast, it would be a good idea to bring the container indoors until the storm has passed, to keep the contents from getting wet. And if squirrels damage the container or carry it off, you still could offer string and yarn for birds. Just cut these into 6-inch lengths and drape them on tree branches and twigs. To augment the string and yarn, you could rake up some of winter's accumulation of twigs into a corner of your yard, along with some of your old leaves, and let birds pick through the pile for construction materials.

Hawks and feeders

Q: It seems that a Cooper's hawk couple have come back to nest in a tree in my back yard, as they did last year. The hawks are dramatic and entertaining, but the songbirds get very quiet when they're around and I'm wondering if I should retire my bird feeder until the hawks move on.

A: That's a very good question, and I salute you for caring about both the hawks and the songbirds. If the hawks do establish a nest in your back yard, it will be very hazardous for small birds visiting your feeder. As you know, Cooper's hawks feed on other birds, and they'll need plenty of food as they raise their nestlings. Once one of the hawks discovers how easy it is to hit a goldfinch or cardinal at your feeder and carry it away, they'll return time and time again. So I would recommend that you take down your feeder until the hawks have raised their brood and dispersed from the area, which could be late June or early July. The hawks will still be catching small birds, but they won't be those lured in by your feeders.

Sparrow deterrent

Q: The sparrows have taken over my feeders and kicked all the other birds out. I stopped feeding and they disappeared for a week, but came right back when I put food back in the feeders. Any ideas for getting rid of sparrows?

A: Sounds like you're a good candidate for a device called The Halo; many people swear by these sparrow deterrents. You can buy one or make one yourself — start here to get an idea of what's involved: http://tinyurl.com/kny8aum.

Dive-bombing robin

Q: A robin dive-bombs our windows for hours at a time, leaving marks where it hits the glass with beak or claws. Have you ever heard of this? What can I do?

A: Your robin is exhibiting a fairly common behavior at this time of year. With hormones at their seasonal peak, birds are intent on attracting a mate and driving away any competitors. Robins, cardinals, blue jays, bluebirds and even goldfinches try to fight their reflection in windows or car mirrors, not realizing that they're seeing themselves. The behavior subsides after nesting is well underway and hormones calm down. But it's no fun for homeowners and car owners in the meantime. The key to stopping the behavior is to stop the reflectivity of the window by placing cardboard on the outside of the window being attacked. If the bird moves to another window, place cardboard over it. Closing the curtains doesn't end the problem, because windows still have some reflectivity. I hope you will give the cardboard barrier a try, for your peace of mind and because birds can harm themselves during their relentless attacks.

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 val​writes@comcast.net.