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On the Wing 

Damselflies and moths

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Photo by Anthony Westkamper

Damsels in fall

The unseasonably warm and dry weather seems to be allowing some species of insects to linger later in the year than I've seen before. Among them are two damselflies. I checked my archives and this is the latest date in the year I've ever noted either the rubyspot or California spreadwing (Archilestes californica).

I don't really have one favorite bug; I have many. Some for intriguing lifestyles, some for their oddity and some for sheer beauty. One of the last group is a male damselfly, the American rubyspot (Hetaerina americana). Like most damselflies, they fold their wings over their back when resting, hiding the brilliant red coloration which gives this common fall species their name. Like all members of Odonata (damselflies and dragonflies), they are predators. Taking up a prominent perch usually overlooking water, they chase after anything that flies within a couple of meters.

So, I set my camera for a high-speed series of exposures, took up a position and waited. And waited. Finally, the rubyspot damselfly dashed out but was out of my field of view before I managed to press the shutter release. It did return, however, while I was still holding down the button allowing me to capture some frames as it stuck the landing. The red on the wings is prominent but even the images produced by my best camera/lens combination lose something. I suspect the wings reflect into the violet part of the spectrum, which does not transmit well through optical glass lenses. Some insects can see farther into the ultraviolet than we can. This may make the gaudy coloration even more attractive to a potential mate or intimidating to a rival.

I mentioned that unlike their cousins the dragonflies, damselflies usually rest with their wings folded over their backs. The exception to the rule is the family known as "spreadwings" (lestidae). I think these may be what I call "relict" populations — now out of the business of reproduction, they are merely living on instinct until cold weather kills them off.

Lepidoptera (butterflies and moths)

Walking along the Van Duzen River after three frosty nights, I noted four different kinds of butterflies. We saw many Mylitta crescents (Phyciodes mylitta), got a brief glimpse of what was most likely a woodland skipper (Ochlodes sylvanoides) and a West Coast lady (Vanessa annabella). A California sister (Adelpha californica) flitted up and posed at the last minute.

Butterflies and moths make up the order lepidoptera. Although butterflies get a lot more attention, many experts find moths more interesting. Typically, butterflies fly in day and moths by night. While butterfly antennae are thin and end in a knob, moth's antennae have other shapes, from thin filaments to elaborate fronds. In North America it is estimated there are about 700 species of butterfly, while moths may number more than 11,000. Some experts consider butterflies merely a family of day-flying moths.

In the age-old arms race between insectivorous bats and night flying moths, moths have developed several survival strategies. One strategy is early detection of the bat's sonar, which triggers evasive flying tactics. Others have developed a form of acoustic stealth. Many night-flying moths are extremely fuzzy. A recent article in Science News points out that this fur can deaden the bat's sonar echoes.

As there are so many more types of moth than butterfly and they have been around so much longer, it stands to reason they might have an even more diverse set of lifestyles. Like butterflies, the majority of moths mainly eat higher plants as larvae and sip nectar as adults, but there are exceptions. Some moth larvae are known to eat natural fiber fabrics, a couple of species of wax moths inhabit beehives, eat wax and can actually digest some plastics.

Perhaps the oddest moth lifestyle is that of the genus Calyptra. Known as "vampire moths," they do indeed suck blood from higher mammals, but have no fear, that group doesn't live anywhere near here. Yet.

Read more of Anthony Westkamper's HumBug on Sundays at www.northcoastjournal.com.

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