One of the major natural wonders of summer-time is the profusion of butterflies. Some call them flying flowers which is very appropriate given both their beauty and their association with flowers as a source of nectar. Although their variation and diversity can be a source of confusion, it is very helpful to learn the most common species first. So here are some of the most abundant butterflies in our farm yard this week.
At the top of the list are the swallowtails, of which the tiger is the most common. However it is confusing since it comes in a yellow and black morph. All males are yellow as the one shown here on a pink thistle flower, and have narrower black stripes on the fore wing and little blue on the hind wing in comparison with the female. The black stripes, including one right down the center of the body of the yellow morph, seem to have the function of diverting attention away from the body and head. Strangely enough we have few yellow females; most of the females are dark as is the individual shown sitting on burdock in our yard. These “black tigers” show some hints of dark stripes with lots of blue on the hind wing; note how the blue color of the wing is present in individual scales. It is believed that this black tiger morph benefits from being a mimic of the toxic pipevine swallowtail, which would be avoided by predatory birds. The coloration and shape of the hind wing with the tails and orange eye spots is also thought to function as a head mimic, diverting the strikes of predators away from the more vulnerable head and body. But no matter how you analyze this butterfly, it is a thing of beauty as well as some scientific mystery.
Another group of butterflies in these fields are the fritillaries which are much more plainly colored. Although great spangled fritillaries are common earlier in the summer, at the moment variegated fritillaries are seen most often. They are particularly attracted by late blooming butterflyweeds which have come up in fields that were mowed June 25; this removed the fescue and allowed warm season grasses and flowers to thrive. Note how dull in color and camouflaged this species is; clearly it is not advertising its presence. A few meadow fritillaries which are smaller and similarly colored are present and one was seen drinking from some biosolids. The predilection of butterflies to congregate on and drink from various sorts of organic material of animal origin and from water sources which contain salts reflects their need for sodium. This is a common problem with herbivores whose diet is high in potassium but not sodium; hence the common use of salt licks. A large group of orange sulphur butterflies and some eastern tailed blues were also “puddling” along our dirt road sipping up the soil water which must contain the desired sodium. You should be able to see how each sulphur has its proboscis extended into the soil. You can even attract butterflies by putting out wet sand which has a dilute solution of sodium chloride in it.
A common group of butterfly relatives in our yard that are very frustrating to identify are the skippers. We have many of these but I do not attempt to determine more than a few of the species since they are so difficult to tell apart. Skippers have large bodies and short wings which they hold out at an angle. One that is obvious is the common checkered skipper, which is well named. In our Florida yard we have one of the most beautiful and distinctive species, the mangrove skipper. It has iridescent blue streaks and patches.
So do not despair, you can easily learn to identify the common butterflies of your area first, and then progress one by one to the less common and perhaps more difficult species to learn. This bootstrap method of gradual progression in knowledge is a good technique to follow for learning dragonflies or plants or whatever taxonomic group that interests you. While there is nothing intrinsically special about knowing the name of something, it is tremendously powerful to be able to recognize individual species since this is the means by which you can begin to make observations on behavior, ecology and thus look for patterns. I find that pattern recognition is the holy grail of ecology and provides special satisfaction to the nature lover. It explains why I find great pleasure in returning to the same habitats time and time again to see how things have changed, or not.
Bill Dunson, Englewood, FL & Galax, VA
wdunson@comcast.net