This guy is one of my favorite photographic subjects, the elusive Black Phase Tiger Swallowtail, Papilio glaucus. In my universe there is nothing more enjoyable than walking through a garden, camera in hand, trying to capture a great image of a butterfly. They’re both beautiful creatures and challenging subjects. The thing is, even if you don’t get an amazing shot, it’s still a great way to spend an afternoon. If you are persistent and patient, soon or later you’ll bag a good shot.
The black phase, or dark form, Tiger Swallowtails are a particular challenge. All the dark form Tiger Swallowtails are female, but not all females are dark, so they are a subset of the overall population. There is no definitive information on the percentage of dark forms relative to the population, but it’s believed that the dark forms are more prevalent in areas with large numbers of Pipevine Swallowtails. The two species look quite similar, but the Pipevine Swallowtail has an extremely bitter taste. This mimicry gives the black phase Tiger Swallowtails a better chance of survival.
In my area of the Carolina Piedmont it seems that about 30 or 40 percent of females are dark form. Females of both color morphs have blue markings near the trailing edge of their wings which makes telling males from females easy. The female’s blue and yellow-orange wing markings are slightly iridescent so if you’re lucky, you might catch the right sun angle and capture that added sparkle.
When I find one in the field that’s not too weathered, I’ll chase it as long as I can. The chase is half the fun, it’s not like a little exercise is going to cause problems other than a few sweat stains. Constantly moving, watching the light, and adjusting the camera settings is all part of the game. In mid summer when Swallowtails are most active, they move fast and often. This is hand held, long focal length, macro lens territory. Most of the time I use my Sigma 105mm EX Macro lens with a 1.4 teleconverter, on the crop sensor Sony A77. Not the lightest package to carry around, but it’s fast to operate and when you nail the focus it delivers the goods. Can’t ask for more than that.