The Carolina grasshopper, Dissosteira carolina, ranks among the most common species of Orthoptera on Martha’s Vineyard, and also among the most easily found and recognized. With notable regularity, the first adults take wing around the second week of July (the 14h of the month was when I noticed my first one this season). And the species can be found most years into early November, when cold weather puts an end to their capers.
When in flight, a Carolina grasshopper is hard to miss, and instantly identifiable. This large species, about two inches long, is a member of the subfamily Oedpodinae, or band-winged grasshoppers, and like most of its relatives, the Carolina grasshopper has boldly colored hind wings that show in flight. The majority of a Carolina’s wing is solid black, and a margin, ranging from off-white to distinctly yellow, occupies the outer fifth or so of each wing. No other grasshopper in our region has mainly black hind wings, so this field mark is a fully reliable one. (If you confuse one with anything, it’s likely to be a mourning cloak butterfly, which is roughly the same size and shows the same dark, pale-bordered wings.)
If only it showed all the time! At rest, with the striking hind wings hidden beneath leathery forewings, Dissosteira carolina is something of a chameleon, easily confused with other band-winged grasshoppers. While reviewing my grasshopper photographs recently for a writing project, I was mortified to realize that close to half the photos I had filed over the years as this species actually showed something else!
For one thing, Carolina grasshoppers are wildly variable in terms of color. The standard coloration, to the extent that there is one, is pale brown; but individuals also turn up in gray (sometimes nearly black) or reddish, or yellowish, and there are infinite gradations between those basic colors. Carolinas always show some degree of dark mottling, which is somewhat helpful, but basically you can’t rely on color to recognize this grasshopper.
Body structure in grasshoppers varies much less than color, as a rule, and the real key to recognizing a sitting Dissosteira carolina is to focus on how it’s built. Like a lot of band-winged grasshoppers, this one has a raised ridge or keel running along the top of its thorax. That ridge, in species that have one, is usually divided at least once by a cut or notch. But in Carolina grasshoppers, the notch has a unique shape: It’s gaping, asymmetrical, hooked on one side, and strikes my eye as looking a bit like something you’d use to pry tops off beer bottles. It sounds arcane, but once you get a feel for that notch shape, this mark will serve you well.
I find this grasshopper nearly everywhere: pastures, pond edges, yards, roadsides, even on the beach at times. And it is present in good numbers most seasons. Like most of our grasshoppers, Dissosteira carolina spends the winter in egg form, hatching in early spring. Recent hatchlings are rarely seen, but by mid-May, the nymphs have grown and molted several times, and become pretty easy to spot. About three-fourths of an inch long at this point in the season, they already show the notch on the thorax. But the wings are not yet developed, so nymphs can neither fly nor signal their identity in the air.
A couple more molts brings them to maturity, and with little delay the species turns its attention to producing the next generation. Mating, as is usual for grasshoppers, is a protracted process, and linked couples can be quite oblivious to disturbance: You may be able to pick them up in your hand for a closer look. Females lay eggs underground, generally in fairly dry sites as far as I can tell, patiently working the tips of their abdomens into the ground before depositing a bunch of eggs.
This grasshopper seems to eat a wide range of plants, both grasses and broad-leafed species, and dietary flexibility surely contributes to the broad distribution of Dissosteira. While a grasshopper this size can eat quite a bit, Dissosteira carolina doesn’t seem to reach pest levels of abundance on the Vineyard. On the other side of the table, these grasshoppers are frequently preyed on by birds — nymphs by ground-hunting species like robins or towhees, while adults can be taken in flight by aerial predators such as the Eastern kingbird.
I find Carolina grasshoppers to be rather wary and difficult to approach. And as soon as something makes them nervous, they launch into strong flight. Typically, they’ll land again in 30 feet or so. But this species is capable of long flights, and it’s not unusual to see one motoring along a fire lane in the State Forest, clearly relocating in a significant way. And that mobility is another factor that must contribute to the success of this species.
This excellent insect is at its peak of prominence right now. Look for it wherever you go on Martha’s Vineyard.