Natural Curiosities

Q.I saw a chipmunk outside our patio door with a dying mouse in its mouth. Was the mouse a competitor?

Chris Lotzer

Buffalo

A. Meal is more like it. Although usually vegetarian, chipmunks and other woodland squirrels sometimes eat small animals, including snails, frogs, worms, insects, and mice.

Q.Last fall I observed a large concentration of dragonflies headed south. Do they migrate?

David Parker

Plymouth

A. The dragonflies you saw were probably green darners (Anax junius). Found statewide, green darners begin breeding on shallow lakes, ponds, and backwaters in April. In August and September, the new generation flies south. No one knows for sure where these dragonflies go.

Q. What makes a river a river? I have seen many rivers that are much smaller (and appear more shallow) than many bodies of water designated a creek or stream.

Valinda McCarter

Minneapolis

A. Stream is a generic word used to describe either a creek or a river, says DNR Waters program supervisor Glen Yakel. Although there are no universally accepted rules to distinguish between the two, most people think of creeks as smaller than rivers. However, you may occasionally encounter a place where a named river runs into a named creek. This is a result of local usage, and has nothing to do with the size of the respective streams.

Q. Last year I did not see any wrens, and there seem to be none this year. I normally had more than one pair. I’ve had them come back to my birdhouses for years until last year. Did West Nile virus get this little bird?

Marvin Hernwall

Garfield

A. That’s a possibility–but so is a cat, a jet engine, an owl, a parasite, or one of numerous other causes of mortality in birds. If there have been no major habitat changes in your vicinity, another pair will probably take over your welcoming accommodations soon.

Q. Two summers ago a neighbor had a caterpillar that lit up like a firefly. The glow was like a diagonal stripe. What was it?

Mrs. Morris Evans

Comfrey

A. It might have been a firefly. Also known as lightning bugs, fireflies (family Lampyridae) are famous for their blinking lights, which attract mates. The larvae are sometimes luminous as well. Active at night, larvae can be seen in marshy areas under leaf litter or decaying vegetation, feeding on bugs, snails, and other small creatures.

Q. I sometimes give the ducks in the pond behind my house cracked corn. I hope this is good for them. Is it?

Kelly Hoopman

Apple Valley

A. While not ideal waterfowl food, says DNR duck expert Ray Norrgard, cracked corn will not cause any harm as long as you store the feed in a dry place and the birds clean up all the corn at each feeding. Wet corn can attract fungi that can kill the birds. During spring and summer, ducks and ducklings need a high-protein diet. The best source of protein is aquatic invertebrates such as insect larvae, snails, and crustaceans, not corn.

Q. How long does it take turtle eggs to hatch?

Bruce Lindfors

Princeton

A. Typically 70 to 80 days. Weather affects the timing because turtles lay their eggs in a hole in the ground, bury them, and leave them to be incubated by the warmth of the sun, says DNR amphibian and reptile specialist Carol Hall. The hotter the summer, the more quickly the eggs develop and hatch. Most turtles lay eggs in early to mid-June, and hatchlings emerge in mid-August to early September. Some overwinter in the nest as hatchlings. They emerge the following spring.

Q.Our bird feeders at our home near Bruno have been demolished. We think it’s bears. Is there a particular time of day or night they come out? Do we have reason for worry if we walk outside?

Mary Rynerson

St. Paul

A. Many northern Minnesota residents don’t feed birds in the summer because of bear concerns. Once black bears find a food supply, they will return regularly and become a nuisance. Black bears are active mainly during the day. They rarely attack humans, but may suddenly become aggressive in defense of their space, cubs, or food. For a free pamphlet called Bear Country: Learning to Live With Bears, contact the DNR Information Center (see page 79).