What's up with house wrens?

Q Every year we look forward to the arrival of our favorite bird, the house wren. This year we haven't seen or heard a single wren. Where have they gone?

A It can be a mystery why a bird species will be around for years on end, then not be seen for a while. Birds can be "spotty" like this. For example, a number of readers lamented this spring that they hadn't seen any orioles, yet other readers wrote that they were inundated with them.

In the case of the wrens, there may have been a change in the local ecology or the wrens found another address. If you have a log pile, stone wall or wren nest boxes you're almost guaranteed to host wrens, either this year or next.

Switch up suet Q I like to put out chunks of raw suet all year round for birds. Will this go rancid in hot weather? I can switch to those suet cakes but the birds seem to prefer the real thing.

A I'm sure your birds appreciate suet to replace energy lost during the busy nesting season and to feed their youngsters. But raw suet can become rancid in the heat. Even worse, it starts to melt on hot days and can drip onto bird feathers. They can't remove this oily mess and it impairs their feathers' ability to keep them waterproof and insulated. So I would strongly recommend suet cakes in the warm months.

Squirrel trapping issues Q My neighbor has been trapping gray squirrels and releasing them across town because he's tired of them getting into his feeders. I don't think this is a good idea, but don't know why.

A This is a heartless and useless idea for a lot of reasons. For one thing, at this time of year, an adult squirrel trapped down on the ground likely is a mother squirrel anxious to feed before going back to her brood. If she's taken away, her young will die a lingering death.

It would be better if your neighbor put his energy into outwitting his pesky squirrels. Try a Google search for "Cornell Lab outwitting squirrels," which will point you to an excellent, downloadable file you can print out for your neighbor.

Window safety Q I've lost the column I clipped earlier this year -- could you list again some sites for making home windows safer for birds?

A The windows in our homes take a terrible toll on birds, so kudos to you for wanting to make your property safer.

The Audubon Minnesota site has good, comprehensive information: mn.audubon.org/birdsafe-homes. Another good site is at birding.about.com/od/birdconservation/a/prevent windowcollisions.htm.

Two good commercial products are window decals that reflect UV light: www.windowalert.com, and window tape: abcbirdtape.org. You can find these two products at wild bird supply stores locally.

A Thanks for your observation, and even though I've never seen this myself, I'd bet it's not all that unusual. Jays and woodpeckers are smart birds that watch what other birds are up to, and then may copy their behavior. They both dine on fruit and berries in the fall, so it must seem like an out-of-season treat to find your saucer of jelly hanging outdoors.

Sandstone swallows Q I noticed some road construction in a rural area had left an expanse of exposed sandstone. It was riddled with holes and some small, swooping birds seemed to be busy bringing in food. Could these have been barn swallows?

A Thanks for sharing your interesting observation. It sounds like you saw a colony of bank swallows, small birds that catch flying insects for their young and themselves. It's their habit to excavate nest burrows in riverbanks, gravel pits and highway cuts, and, being social birds, they live in large colonies. (Barn swallows, on the other hand, build their nests out of mud and attach them under bridges and eaves.)

Eagle food Q I was interested in the recent question about an eagle eating a rabbit. My guess is that the eagle didn't catch the rabbit but found it dead on the road.

A I'm sure you're right, that this almost surely was a scavenged meal. Live rabbits move too fast to be caught by an eagle. But eagles are famous for scavenging and this one was doubtless pleased to find some roadkill.

A Barn swallows are very persistent little birds, as you've found. The best solution is to exclude them from that air vent area, either using heavy-duty bird netting or chicken wire over the site. Another approach is to hang heavy plastic, the theory being that swallows can't attach their mud nest base to the slippery surface. (The Washington Department of Fish and Wildlife has an excellent downloadable pamphlet on this topic at wdfw.wa.gov/living/swallows.html.) Remember, it's not legal to take down nests after the birds lay eggs. People who really want to help barn swallows can place a nesting platform some distance from a home's doorways and utility structures.