Prairie wanderings: Wasps, weasels, bats, and flies
By PAUL G. JANTZEN
Contributing writer
A seasoned college biology teacher once told me that learning is really fun, and teaching involves continuous learning. One factor that has helped me learn is the questions people ask. I here review several such instances.
A student brought me a fleshy green caterpillar of possibly a tomato hornworm, its back covered with white cocoons standing on end. The cocoons, I learned, may have been those of a tiny parasitic wasp. These wasps lay their eggs in live caterpillars which the hatching wasp larvae eat. Caterpillars not attacked by wasps feed on tomato leaves during the summer and fall. They become adult moths which are a mottled dark gray with five pairs of yellow spots on the sides of the abdomen. They have a wingspan of about 4.5 inches (114 mm). The larvae of tachnid flies also parasitize many kinds of caterpillars and other insects.
So, when we use a spray to control these caterpillars, we also destroy their natural enemies.
Our daughter Lisa, who lives near Middle Creek, brought me a shiny black beetle about an inch (25 mm) long for identification. The jagged orange stripes across its wing covers the golden hairs under its black thorax identified it as a yellow-bellied burying beetle. This beetle is attracted to the dead bodies of mice and small birds through its keen sense of smell. The beetle removes soil from under the corpse until it is lowered into the ground. The female beetle then lays eggs in the dead body. As young beetles hatch, they eat the dead flesh until they mature.
Over 1,000 other kinds of beetles in this family plus various maggots and countless kinds of decay bacteria and fungi help to eventually return the nutrients of dead bodies back to the soil. These nutrients are then available to green plants that provide food for the next generation of animals.
During the winter of 1987, Clara Bartel was startled by a white mouse-sized creature in the doorway of her bathroom. Intimidated by its aggressive appearance, Clara called a neighbor for help. He killed the furry animal and tossed it into the alley.
Two weeks later, she called to report her discovery. I found it easily in its white winter pelage. She had encountered a least weasel, Kansas' smallest carnivore.
Least weasels are most common in grasslands feeding on voles, deer mice, harvest mice, a few birds, and insects. The first verified capture of least weasels in Kansas was in 1964 in northern Kansas. By 1985 they were reported in Harvey and Marion counties and in 1987, in our town.
Back in 1993, neighbors Laura and Suzy Lindsay invited me to look at a bat knocked to the ground by the previous night's storm. After observing the bat's intricately folded wings and her two young suckling at her breasts, I photographed the young family for more careful identification and released them near the shrubs and trees lining the North Cottonwood River.
Adding the photos taken of a bat Elaine and I rescued one night in 1958, I sent the pictures to Thorvald Holmes Jr., of the Kansas University Museum of Natural History. He identified both as red bats, one of at least 14 species of bats found in Kansas. We recalled the day we recorded 32 small, long-horned grasshoppers devoured by our 1958 bat.
After a day of canning meat for overseas relief, fellow worker Olin Ensz asked what I knew about the green spiders he finds in the nests of the mud dauber wasp. I told him I knew nothing about them but would try to find out and let him know.
The female black and yellow mud dauber builds a mud nest containing many chambers. In each chamber she deposits several paralyzed spiders or small insects. She then lays an egg in the cell and seals it. After the wasp larvae hatch, they feed on the spiders.
Blue mud dauber wasps often occupy the old nests of black and yellow mud daubers after cleaning out the old chambers and furnishing new spiders before laying an egg in each cell.
Neighbor Suzy Lindsay brought what looked like a large ant safely contained in a lidded glass jar. What she found was Kansas' largest velvet ant, a female common eastern velvet ant measuring up to 18 mm (0.7 inch) in length. Actually it is a wasp. While the male appears much like other wasps, the female is wingless and hairy. The hairs on its back are reddish-orange. With her fierce sting, she kills other wasps in their burrows and lays eggs on the victim's larvae for her own larvae to eat when they hatch.
A local resident asked about the flies collecting on the window sill above a sink used occasionally for washing pots and pans.
I scooped up a dozen dead flies and took them to Tabor College entomologist Richard Wall for identification. He immediately recognized them as moth flies or sewer flies. They breed in sink traps, he said, especially in accumulations of organic matter.
The 2000 edition of "Insects in Kansas" describes them as a common species that also occurs on the walls of outdoor toilets and in drain pipes. They are one-eighth inch long (3 mm), have elliptical wings and are covered with gray hairs. There are white dots between the veins along the wing margins.
Indoor remedy: clean the sink drain with Drano.
