The Daily Bucket is a regular series from the Backyard Science group. Here we talk about Mother Nature in all her glory, especially the parts that live nearby. So let us know (as close as you are comfortable) where you are and what's going on around you. What's the weather like? Seen any interesting plants, bugs or critters? Are there birds at your feeders? Deer, foxes or snakies in your yard? Seen any cool rocks or geological features? Post your observations and notes here. And photos. We like photos. :)
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Obscure Birdwing Grasshopper
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There are about 20,000 species of grasshoppers and crickets worldwide, in the insect order Orthoptera (from the Latin words for “straight wings”). Some 12,000 of these are grasshoppers, which are made up of three large families.
A number of grasshoppers are popularly known as “locusts”, mostly because some members of this group form huge hordes which then travel across the countryside devouring every scrap of edible vegetation. “Locust plagues” figure in many stories, both fictional and historical. Only a small minority of “locust” species ever actually form such destructive swarms, though: most members of the group are just large inoffensive grasshoppers who never cause any trouble.
Some of these “locusts” are in the genus Schistocerca. These are large grasshoppers who are well-known for their strong wings and their superior flying ability, which has earned them the common name “Birdwing Grasshoppers” or “Bird Grasshoppers”. Although one of the most notorious swarming insects, the Desert Locust Schistocerca gregaria, belongs to this genus, most of the Bird Grasshoppers are solitary and cause no harm.
Of the 70 or so Grasshopper species which can be found in Florida, six are members of the Birdwing Grasshopper group, and one of these, the Rosemary Grasshopper S ceratiola, is only found here. The most often-seen of the Birdwing Grasshoppers in Florida, though, is the Obscure Birdwing Grasshopper, S obscura, which can be found ranging from Pennsylvania down to Florida and across to Arizona.
The Obscure Birdwing Grasshopper was first scientifically described in 1798 from a specimen that was collected in Kansas. Some authorities have advocated lumping S obscura together with several other species as mere subspecies of the widespread Leather-Colored Birdwing Grasshopper, S alutacea.
S obscura is a very large grasshopper, bright green in color with dark brown wings and a distinctive yellow stripe running down the back, though this is sometimes lacking in some females. There is also a yellow spot on the sides of the thorax.
In Florida, the Obscure Birdwing is often confused with the far more common Eastern Lubber Grasshopper, Romalea microptera. Both are very large colorful grasshoppers up to three inches long, but the Birdwing Grasshoppers belong to the Acridid family and the Lubbers are members of their own Romaleid family.
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Eastern Lubber Grasshopper adult
Eastern Lubber Grasshopper nymph
Although many insects which bear bright yellow contrasting markings are toxic to birds and other predators, the Schistocerca species do not produce any such noxious chemicals. The yellow stripe may be an attempt to mimic the much more common (and toxic) Lubber Grasshopper nymphs, but the Birdwings themselves are entirely palatable to birds and other insectivores.
However, like all of the Birdwing Grasshoppers, the Obscure Birdwing is a very good flier, and while most grasshoppers merely buzz away unsteadily for a short distance, Birdwings can soar away for long intervals with a strong and steady flight, looking like a small bird (thus, the name). This allows them to easily escape predators and also to forage over a large area.
In general, the females are much larger than the males, almost twice the size. Mating takes place at the end of the summer, and the females will lay a large clutch of eggs in sandy soil using her ovipositor. These will overwinter underground and hatch in spring to produce nymphs, which look like tiny copies of the adults but without wings and with a darker color. Like all insects, grasshoppers must periodically molt their exoskeletons in order to grow, and Birdwing Grasshoppers usually molt nine times over the course of a year before reaching adulthood. Only the adults have fully-developed wings.
The primary food seems to be grass, though they can eat a wide variety of other plants and they sometimes congregate on Hibiscus bushes. They also show a preference for citrus foliage, but do not exist in large enough numbers to be a serious agricultural pest in Florida. Like most grasshoppers the Birdwings like sunny open areas such as fields or meadows or lawns, where they can find abundant food plants.
And now it is your turn: what’s hopping around in your neck of the woods?
We are always looking for new people to produce Daily Buckets, where we practice "backyard science" by reporting and recording what we have seen in the natural world around us (and no matter where you are--even in the middle of the city--there is nature around you). You don't need any science degrees or training or in-depth experience to be a backyard scientist, and you don't need any expensive camera equipment or photo-editing software to do Daily Buckets. All you need is a pair of eyes and ears, a phone with a camera, and a lot of curiosity and enthusiasm.
