Herons herald spring

Q When do the blue herons return?

A The first great blue herons typically appear in the state by mid-March, though a few birds usually winter here along the Mississippi River.

If you have a lake cabin, you can expect your local herons to return after ice-out. By the beginning of April, most large roost colonies in the state will have birds on them, repairing and building their large platform nests.

Owls at home Q We have a saw-whet owl nesting in one of our wood duck houses. Could it have been driven to find shelter by our cold winter?

A Northern saw-whet owls and Eastern screech-owls are known to roost in nest boxes built for wood ducks, so the bird in your yard wasn't driven by the cold. It's likely that the bird is an Eastern screech-owl because saw-whets are rarely found in the Twin Cities.

Owls don't excavate, which makes them dependent on finding a suitable cavity. They look for cavities made by another bird (usually woodpeckers) or artificial ones. As people cut down standing dead trees and prune dead limbs, nesting cavities become more difficult to find.

Owls use cavities for roosting year-round. Because they roost during the day, it can appear as if they are nesting. If you want to find out for sure, try to peer into the nest with a mirror.

A You can, but curing bacon involves a concentration of salt, preservatives and other chemicals that may not be good for the birds visiting your feeder. We suggest using rendered beef fat as suet instead.

After rendering, you can add bits of bacon or any number of other ingredients including peanuts, berries or seeds.