By By Bill Danielson
As we begin the month of July, we find ourselves in an interesting moment in the year.
Most of the birds have already had their first round of chicks, and some species may try for another round of breeding. Other species of birds have made their only attempt at reproduction, and, successful or not, they will not try again. It is something that you can actually hear across the landscape in the early morning. Some species are still singing, while others are now quiet.
The world of insects has some similar patterns, but the majority don鈥檛 make much noise, which means that you have to go outside and actively look for them to find them. With birds, you just listen and turn your head in the right direction. With insects, it is a much more active and demanding pursuit to find them, but sometimes you can stack the odds in your favor by simply planting a pollinator garden.
Today, I introduce you to the question mark butterfly (Polygonia interogationis). For my money, I would place this species at the top of the 鈥淢ost Beautiful鈥 list for our local butterfly species. You may have a personal favorite that you think could challenge the question mark for this top position, but I鈥檓 going to need a lot of convincing to change my mind. This species has a velvety softness to its coloration and the spectacular contrast between black and a light robin’s egg blue along the outer margins of the wings. Gorgeous!
So, where can one find a question mark? (Other than at the end of that last sentence?) Well, homeowners are in luck if they live near the woods. The question mark is a species of woodlands, where it can find one of its favorite host plants, the American elm (Ulmus americana). Sadly, the American elm is a species in real trouble because of a fungal infection known as Dutch elm disease, which was accidentally introduced to North America in the 1920s and 1940s. This disease has run through elms like a fire through dry grass, but we are fortunate that the question mark has other species that its larvae can feed on; most notably nettles (Utrica species).
AMPLE OPPORTUNITY
Since both of these very different sorts of plants live in forests and open places, respectively, the question mark is a species of forests and forest edges. It is also a species that has three different generations in a given year, which means that it will seem to be present during spring, summer and fall. The first set of adults appear in the middle of June, the first brood generally appears in the second half of July, and the second brood appears in early October. This means that there is ample opportunity to find one and, as a bonus, possibly the two different forms of the species.
鈥淪ummer鈥 question marks have a coloration like the one that you see in today鈥檚 photo. The forewings are orange with black spots and the hindwings are mostly black with a trim of blue. These are the butterflies to look for in a couple of weeks, and they should be at their peak of abundance for two weeks after that. The adults will rely on their amazing camouflage to avoid predators, appearing as nothing more than dead leaves. There is a curious silvery marking on the underwings that someone thought looked a little like a question mark, and thus the name of the species was decided. However, it is the top of the open wings that are particularly beautiful.
MIGRATE SOUTH
Question marks that emerge in October have a different look. The hindwings of this third generation are more of a dull chocolate brown, and the blue edges just don鈥檛 鈥減op鈥 on this form in the same way. The most extraordinary thing about this last batch of butterflies is the fact that, like the monarch butterfly, the question mark is migratory. Large 鈥渨aves鈥 of these butterflies can be seen headed south before winter arrives, but it is not known exactly how far they go. How, after all, would we be able to track individual butterflies? There are also places where the species will hibernate for the winter, but how do you tell the difference between migrants and residents? Science can be tricky!
The 鈥淔all鈥 question marks are the ones that finally appear in June as adults. Courtship flights commence with the males perching in exposed locations where they can get a good look at the world. When something moves through their field of view, the males will launch themselves to investigate. This means that they will chase other types of insects and sometimes even birds. The males release pheromones to attract females and then they must closely scrutinize anyone who comes near. Once a female is located, mating will commence and then the females will lay their eggs, often on plants that are not food for their offspring. The tiny larvae that hatch out of the eggs have to go in search of their food, which is a bit odd.
Your mission, should you choose to accept it, is to prepare yourself for an expedition into the woods in two weeks. Scout out some promising locations that have forest edges where fields abut woods, and then get out and see if you can locate a 鈥渟ummer鈥 question mark. Males and females look alike, so that鈥檚 one less thing to worry about. (I鈥檇 like to say that this message would self-destruct in 5 seconds, but we honestly don鈥檛 have the budget for that.)