Q: I've been noticing more and more wild turkeys around the metro area and have been wondering what their nests look like.

A: You're right, turkeys are becoming more prevalent in our cities and suburbs. A female turkey scratches a shallow depression on the ground to hold her eggs, usually in a wooded area. She incubates the eggs for about 28 days, then leads her poults away from the nest site. The young turkeys shelter under their mother's wings at night and on cold days.

Screen-shredding finches

Q: Finches are pecking at my screens and causing a lot of damage. Is there any way to stop this behavior and have you ever heard of this before?

A: No, I'd never before heard of finches damaging screens. Your message arrived just as goldfinch nesting season was getting underway, making me wonder if that wasn't a factor. I found a wild bird store page www.startribune.com/a2422 that shows a goldfinch causing significant damage to a window screen. If your screen-shredding finch appears again next year, you'll need to deter it from causing damage. Try hanging Mylar tape or balloons alongside the window under attack, or attach CDs to wires and suspend them nearby. A plastic snake might even do the job. Good luck with this; there's always something new in the bird world.

Coughing duck

Q: On our evening walk around a pond we've noticed a female mallard who seems to have a cough, or possibly hiccups. Might she have an infection and could she pass it to other ducks?

A: I checked with a veterinarian at the Wildlife Rehabilitation Center in Roseville, and was advised that an upper respiratory infection is a possibility, but sneezing and eye discharge would be more likely symptoms. However, ducks preen a great deal, especially now, during molting season, and she might have got a feather stuck in her throat. If the duck seems to otherwise be doing all right, it sounds like you needn't worry about her infecting other ducks.

Fresh water

Q: How often should we be hosing out the birdbath? Sometimes when the starlings get finished with their communal baths the water is grisly!

A: You're right, a troop of bathing birds can really cloud the water, and even add poop to the mix. During the summer, birds make such heavy use of our two birdbaths that we hose them out several times each day. You may have noticed that birds seem to stay away from a really dirty birdbath, so leave the hose nearby and refresh the water often.

Crestless cardinals

Q: We have a pair of cardinals that look a little different from usual, in that neither has a crest. Could they be some sort of mutants, or juvenile birds?

A: These could be young birds from their parents' first nest this year, who haven't yet molted the feathers that create the characteristic cardinal crest. Or they might be older birds who lost all their head feathers at once (the "bald cardinal" effect) and are just now starting to molt those feathers back. Sometimes cardinals suppress their crests for brief periods, when not excited or threatened, but you've observed this pair for some time, so I'd vote for either youth or a fast molt.

No hummingbirds

Q: We've always had an abundance of hummingbirds until this year, when only a few have shown up. They seem to taste the nectar I put out, then fly off without returning. I haven't made any changes in the nectar mixture, so I wonder if there's some problem with the little birds this year.

A: There haven't been any reports of changes in the hummingbird population, so I suspect you're experiencing the rather typical behavior of birds moving to other feeding territories for unknown reasons. They can be fickle little birds, and I've had reports from other readers this year who are enjoying record numbers of hummingbirds at their feeders. I'll bet you'll enjoy many visits to your nectar feeders during fall migration, which starts in mid-August. (One remote possibility: Hummingbirds are said to be able to detect very low levels of soap residue in feeders, so it's best to wash them without using soap.)

Wimpy blue jays

Q: I put out peanuts for blue jays but lately they've been failing to take them. My husband has seen the jays being chased away by orioles and sometimes catbirds. Have you heard of such a thing before?

A: I don't think I've ever heard of blue jays being intimidated by smaller birds. I wonder if the jays could be young birds who don't know yet that they're bigger than orioles and catbirds and don't need to fear them. I'll bet the dynamic will shift fairly soon and at the very least, the orioles and catbirds will migrate away this fall.

Foiling squirrels

Q: Do you have any suggestions for keeping squirrels out of bird feeders? I'm just about ready to give up.

A: I perfectly sympathize with your wish to keep squirrels out of your feeders. They can cause so much damage, and while they're jumping at or sitting in feeders the birds stay away. I'd like to suggest a feeding system that should work perfectly, although it does require an initial investment. We've had this kind of system going in my back yard for 20 years and have never, ever had a squirrel in the feeders.

Here's what you need, in terms of hardware:

• A shepherd's hook — a pole with two or three arms sticking out (get the 8-foot kind).

• A squirrel baffle for the pole — we use the metal "witch's hat" kind, but some folks modify a garbage can lid to fit around their pole.

• For finch feeders, a tall pole that a tube feeder can be screwed into, plus a baffle guard for the pole.

Place the pole in a spot where you can see it from the house (so you can enjoy your visitors), at least 15 feet from any kind of structure or tree — squirrels can jump quite high, and don't forget, they can drop down from branches, too. If you've put the pole out in a spot where squirrels can't jump or drop into the feeders, and you've added a squirrel baffle, so they can't climb the pole, then you should have a squirrel-free system. Hang feeders from the hooks and sit back and enjoy the birds. Squirrels will still visit to glean the seeds that drop to the ground, but they won't be able to get into your feeders. You can find these products at wild bird supply stores, garden stores or on the Web.

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.