Curious young herons hang out on deck

Q: Three green herons showed up on our deck railing in late summer, and spent some time watching the comings and goings of the songbirds at the feeders before disappearing. We've seen these herons on the nearby pond and wetland, but never before on our property. Is this unusual behavior?

A: What a fun sight that must have been, and I'd say this was not unusual behavior by the green herons, especially as your photos show them to be youngsters. I'm betting they recently left their nest somewhere nearby and all the songbird activity at your feeders caught their eyes. Eager to test their flight skills, they soon left to make more discoveries about their new world.

A hawk and zinnias

Q: My granddaughter made a heart shape out of zinnia flowers on our lawn, and later that day we observed a Cooper's hawk eating some of the zinnias. The next day we found a dead Cooper's hawk near the flowers. We assume it was the same hawk as the day before and since we never use chemicals on our property, we're wondering: What killed the hawk?

A: It doesn't seem as if the zinnias contributed to the hawk's death, since many creatures, from bees to butterflies, sip zinnia nectar and goldfinches and sparrows are fans of zinnia seeds. I checked with the Raptor Center, whose staff said that the hawk might have been infected with West Nile virus. There's apparently a high rate of disease this year and it can cause all kinds of odd behaviors, before leading to death.

Safer jelly

Q: Have you heard anything about grape jelly with high fructose corn syrup being bad for birds? I can't believe it's not harmful to them, but it's hard to find jelly without that ingredient. Any thoughts?

A: Good question and I think you're right, if high-fructose corn syrup isn't good for humans, it probably isn't good for birds, either. I made a quick internet search and found many brands that lack that sweetener, including Welch's Natural Concord Grape Spread, Smucker's Simply Fruit, Songbird Birdberry Jelly, Crofter's Concord Grape Spread. Good and Gather Organic Concord Grape Fruit Spread, Duncraft BirdBerry Jelly, and many others. These brands may not be readily available in all stores, but you could order online for next year.

Horning in

Q: I've had a sock thistle feeder for years, but this is the first year that I've noticed many species other than goldfinches eating from it, such as downy woodpeckers, sparrows and chickadees. Is this unusual?

A: That nyger seed is popular with a number of birds other than goldfinches. Over the years I've had downies, chickadees and house finches visiting my nyger-and-chips feeder. This seed must be very tasty and it has a high oil content, which appeals to seed-eating birds.

Noisy crow

Q: Why are the crows around my neighborhood cawing all day long from spring to late summer? I see no predators in the area, like owls or hawks, but still the crows caw while flying, caw from the roof and caw while sitting in the street. Can anything be done to move them out of the neighborhood?

A: Crows, as you know, are great communicators, and they communicate a lot. My suspicion is that you're hearing a crow family calling to each other: Young birds might be begging for food, or for a parent to appear or might be signaling to a sibling perched nearby, etc. Their parents call to stay in touch, and to warn other birds and humans to keep their distance.

I can't think of many measures that might drive crows away that wouldn't also be disturbing to humans (loud radio, banging pot lids, etc.). One suggestion I found online is to find some life-size crow Halloween decorations and place several around your yard, with one lying in the grass, maybe one hanging upside down from a tree limb. This will look like dead crows to the living crows and might frighten them away. Another tip was to hang shiny objects from tree branches (CDs, DVDs, pie plates, etc.), since crows are said to dislike things that reflect light.

As fall comes on, the crows should leave the neighborhood to meet up with other crows and establish nighttime roosts (let's hope this is far from your property).

Horn heads

Q: I noticed two sparrow-like birds at my platform feeder in late August, but they had what appeared to be feather-like horns on their heads, more like bumps than feathers. The birds were streaked all over and somewhat dark. Any thoughts?

A: This strikes me as a very good description of young house finches. Their parents often have two broods each summer, and the second brood could be fledging in late August. Also, juvenile house finches often still have downy head feathers until their molt is completed, and these could very well look like horns.

Black headed cardinal

Q: I have a male cardinal with a black head coming to my feeder, but the rest of him is bright red. What can cause this?

A: I believe that you're seeing a bald cardinal, one that lost its head feathers in a very short time. With their black skin and reptile-like heads, bald cardinals resemble their dinosaur ancestors. Sometimes the baldness can be due to feather mites causing the bird to itch so much it scratches out its head feathers, but this is uncommon.

A more likely explanation is that a few species of birds, especially cardinals and blue jays, sometimes have a gene that leads to an abnormal molt, causing all their head feathers to fall out quickly. This doesn't harm the birds and within a couple of weeks, as the molt progresses, your cardinal should regrow a full set of red head feathers.

Just a few minutes ago I was looking out the window at two dark-headed blue jays. They appear to be siblings and losing their head feathers all at once seems to run in the family.

St. Paul resident Val Cunningham, who volunteers with the St. Paul Audubon Society and writes about nature for a number of newspapers and magazines, can be reached at valwrites@comcast.net.