Q I've seen robins at my birdbath all winter, so I guess they're not a sign of spring. What bird is?

A More robins are overwintering in our area, perhaps because of our warmer winters. In fact, one local birder has seen more than 1,000 robins come to roost in the pine trees near his home. So a robin in early March may not be a migrant from the south, pulling spring behind it.

A more reliable harbinger of spring is the red-winged blackbird. And we're happy to report this species already is filling area marshes and wetlands with its familiar "con-garee" call.

Night hunters Q Why do owls hunt at night?

A Well, not all owl species hunt at night. But those that do -- including our great horned owl and barred owl -- choose night because that's when their prey is most available. Owls hunt primarily small mammals. And these small mammals leave their dens and burrows after dark because darkness gives them cover from many predators. Except owls, of course.

Update that guide Q Is my field guide from the 1960s as useful today as it was then?

A Sort of. The newest ID books are likely to have more and better illustrations and the text is likely to be more informative. In addition, the range -- and even the names -- of some birds have changed since the '60s. Buy a new book. You won't regret it.

Out with sparrows Q House sparrows have taken up residence in our garage. How can I get these messy birds out of there?

A Plug all cracks and holes and keep the doors shut.

Get rid of wet seed Q After a rain or wet snow, there are clumps in the seed in my feeders. Is this a problem?

A Yes, it is.

Those clumps mean the seed has gotten wet. Damp or wet seed is a problem for birds because it's a breeding ground for disease. Check your feeders after each storm and get rid of any clumps of seed. It's also a good idea to empty your feeders every couple of weeks and start over with fresh seed.

Val Cunningham, a St. Paul nature writer, bird surveyor and field trip leader, can be reached at valwrites@comcast.net. Lifelong birder Jim Williams can be reached at two-jays@att.net. Join his conversation about birds at www.startribune.com/wingnut.