Trumpeter swans becoming more common sight on Twin Cities lakes

Q: I keep an eye on the local wetland and there has been a pair of swans on its small lake on many days. I'm wondering if these might be different birds passing through or could they be the same swans? And might they stay and nest here?

A: These are good questions, and not knowing the answers I turned to someone who does.

"If it's just a single pair of swans, then they are not migrants," says John Moriarty, senior manager of wildlife for Three Rivers Park District, noting that several pairs of trumpeter swans nest within a mile of your wetland area, so the birds you're seeing might be one of those pairs.

Moriarty suggested that the walking trail along the lake you watch might make it unattractive to the swans, but if they find a good spot, they may stay to raise cygnets.

And he ended with this heartening news: "There will be more nests in the metro area in the future as the state population of trumpeter swans continues to grow."

Q: I enjoy the cardinal's springtime song and it inspires me to ask whether cardinals mate for life.

A: Cardinals are fairly unusual in the bird world, since a pair typically remains together all year long — they don't split up after the breeding season, as many other species do. The male and female remain as a pair unless one of them dies, but then the survivor will seek another mate. This, in the bird world, is the definition of "mating for life." Cardinals have such a frenetic nesting season — a pair raises two broods during the summer — that they need to pair up and begin nesting quickly.

A: Glad to hear you want to start looking closely at the birds around you, and buying a pair of binoculars is an excellent investment in enjoying them. However, you don't need to shell out big bucks to get a good view because there are many affordable binoculars on the market these days. In fact, the Audubon Society recently looked at a wide range of binos and was impressed with some in the "under $200" category. You can find out more here: audubon.org/news/category-get-game.

Q: We set up a birdbath for songbirds to use for drinking and bathing, but have noticed a crow comes most days and dunks its food into the bath. Usually this is bread that it finds somewhere, and it makes a bit of a mess. Any tips?

A: Some crows like to soften their food in water before eating it, and your crow has found your birdbath a convenient stop for this. Since there's little harm done, other than leaving behind some gunky water, I'd suggest hosing out the birdbath after the crow visits.

Q: After I filled a feeder with seed I'd had for a while, the birds wouldn't eat it. Does seed go bad?

A: Birdseed does indeed get old and lose its appeal to birds. Seeds are full of oils, which is why birds like them, and oils become rancid over time. Generally, most seed will remain fresh for about six months, so if your seed is a year old, it's best to toss it in the trash and start over. It's also a good idea to toss any leftover seed after winter and start fresh in spring. Seed lasts longer if properly stored in a dry container out of direct sunlight.

A: I'm glad you asked this question, and the answer is a clear "yes." As a woodpecker perches on the bag to feed on suet, its feet may become trapped in the woven material. In its struggles to get free the bird can harm itself. And it's not just woodpeckers: Wildlife veterinarian Leslie Reed at the Wildlife Rehabilitation Center says, "Anything involving string has the potential to entrap any bird and should be avoided."

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