If it looks like a hummingbird, flies like a hummingbird, and feeds like a hummingbird, it should be a hummingbird, right? Not necessarily. If it's smaller than a hummer, it's probably a hummingbird moth.
Hummingbird moths are a type of sphinx moth. Every summer readers send me detailed descriptions of a strange hummingbird-like creature. Most report that it's fuzzy, looks like a bee, has antenna, and a long beak. Such detailed accounts, coupled with its habit of hovering above flowers while feeding, make identification easy.
Species of sphinx: About 100 species of sphinx moths inhabit North America. In fact, the first one I ever saw in flight was on the shore of Lake Powell in northern Arizona. And at first, like everyone else, I was puzzled. I thought I had spotted one of the many hummingbirds that inhabit the western U.S. But a quick survey of my field guides introduced me to these curious moths.
Most are active at dusk and after dark, when they sip the nectar of tubular flowers that remain open at night. In return for the meal, sphinx moths pollinate the flowers. The "beak" is actually a long, flexible tube (the proboscis) that stays coiled under the head when the moth is not feeding.
Several species are likely to be seen locally. One is small with a body that's only about an inch long. Others are larger, but still smaller than hummers.
Clearwing hummingbird moths are among the smallest of these fascinating insects. I saw the first ones this year in early June at mid-day. They were drinking nectar from the blooms on my lilac bushes. I approached slowly and was able to observe one carefully for several minutes. I could see its proboscis uncoil as it approached each flower, and its transparent wings were obvious.
The white-lined sphinx has a long white line extending the length of its front wings and a rosy colored stripe across the rear wing. It's heavy brown body tapers to a point at each end and has a series of dark bands across its abdomen.
The other common local species is known by the name of its caterpillar and is probably more familiar to readers who garden. Tomato hornworms, those fat, green, fleshy caterpillars that eat your tomatoes and their leaves, eventually transform into five-spotted hawk-moths.
Adult tomato hornworms are large, gray moths with wingspans of about four inches. A series of five or six bright orange spots on each side of the abdomen helps identify them.
Larval hornworms are called hornworms because of the soft, spine-like & quot;horn & quot; that projects upward from the rear end of the body. Though the spine looks like a stinger, it's quite harmless. When alarmed, hornworms erect themselves in a stiff, sphinx-like pose -- hence the general name of this group of moths.
A tomato hornworm has eight V-shaped white marks on its sides, and its horn is black. Other species are marked differently and may have different colored horns.
Don't be alarmed: If you find hornworms covered with tiny white capsules, be relieved not alarmed. These white objects are pupal cases of tiny wasps that parasitize hornworms and control their numbers. They are harmless to people. By the time these pupae hatch, the hornworm will be dead. The larval wasps consumed the hornworm from the inside before emerging to pupate. .
The life cycle of sphinx moths is simple and includes a complete metamorphosis. Early in the summer females lay up to 300 eggs on the underside of leaves of tomatoes and other host plants such as peppers, potatoes, petunias, and geraniums. In about a week the caterpillars hatch. They feed furiously for the next four to six weeks and molt five times before burrowing underground to pupate for the winter. The following June adults emerge and repeat the life cycle.
Hummer note: By the way, has anyone noticed hummingbirds coming to feeders after dark? A recent thread on a birding list serve I subscribe to had several reports of hummers visiting feeders between 9 and 10 p.m. I'm curious how common such late feeding is. If any readers have noticed this, please let me know.