Just as we were very pleased last month to have the opportunity to hear the sounds of the rarest of the Periodical Cicadas—the Little Seventeen-year Cicada—in the Conewago Hills of York County to thus provide our only record of the species during the Brood XIV emergence in the Lower Susquehanna River Watershed, we were this week delighted to find and record a population of what may be the valley’s rarest cicada experiencing annual flights—the Robinson’s Cicada—just a few miles away at Gifford Pinchot State Park.
Like the Little Seventeen-year Cicada, Robinson’s Cicada (Neotibicen robinsonianus) is a species found more commonly in the southern United States, occurring with scattered distribution in a range that extends west into Missouri, Kansas, and Texas. They are of rare occurrence in the lands of the Chesapeake drainage basin in Virginia and Maryland.
Populations of Swamp Cicadas, also known as Morning Cicadas, are presently in the midst of their yearly courtship rituals. Their songs are easily heard in woods, edge habitat, and suburbia throughout the region during the AM hours. It was while recording the sounds of these common insects in the Conewago Day-use Area at Gifford Pinchot State Park that we noticed a very unique song from high in the oaks, hickories, and other hardwoods along the lake. Listen to this sound clip featuring a group of serenading male Swamp Cicadas. In the background, a Robinson’s Cicada’s song consisting of a pulsing series of raspy buzzes, each about one second in duration, can be heard, particularly starting at 00:40.Dozen’s of Robinson’s Cicadas were heard this week in the large trees of the lakeside picnic grove in the Conewago Day-use Area at Gifford Pinchot State Park. They remained high in the canopy and were glimpsed only when flying to a new perch, so we’ll have to settle for a photo of an individual from the more southerly portions of the species’ range (provided courtesy of AmaryllisGardener, under license: CC BY-SA 4.0). We recorded these two sound clips of males singing in the forested area west of the picnic grove. The first was nearer the park campground. The second was in the vicinity of the nature center building and includes a Wood Thrush and another Robinson’s Cicada in the background.
The Lower Susquehanna River Watershed, and Gifford Pinchot State Park in particular, may currently represent the northern limit of the geographic range of the Robinson’s Cicada. If you’re in the area during the coming weeks, drop by the park and have a listen. And don’t forget to check out our “Cicadas” page for sound clips of all the species found in our area.
Yesterday, a hike through a peaceful ridgetop woods in the Furnace Hills of southern Lebanon County resulted in an interesting discovery. It was extraordinarily quiet for a mid-April afternoon. Bird life was sparse—just a pair of nesting White-breasted Nuthatches and a drumming Hairy Woodpecker. A few deer scurried down the hillside. There was little else to see or hear. But if one were to have a look below the forest floor, they’d find out where the action is.
Not much action in the deer-browsed understory of this stand of hardwoods.Upon discovery beneath a rock, this invertebrate quickly backed its way down the burrow, promptly seeking shelter in the underground section of the excavation.A closeup of the same image reveals the red eyes of this periodical cicada (Magicicada species) nymph. It has reached the end of seventeen years of slowly feeding upon the sap from a tree root to nourish its five instars (stages) of larval development.
2021 is an emergence year for Brood X, the “Great Eastern Brood”—the largest of the 15 surviving broods of periodical cicadas. After seventeen years as subterranean larvae, the nymphs are presently positioned just below ground level, and they’re ready to see sunlight. After tunneling upward from the deciduous tree roots from which they fed on small amounts of sap since 2004, they’re awaiting a steady ground temperature of about 64 degrees Fahrenheit before surfacing to climb a tree, shrub, or other object and undergo one last molt into an imago—a flying adult.
Here, approximately one dozen periodical cicada nymphs have tunneled into pre-emergence positions beneath a rock. Seventeen-year Periodical Cicadas, sometimes mistakenly called “seventeen-year locusts”, are the longest-lived of our insects.Note the wings and red eyes beneath the exoskeleton of this periodical cicada nymph. Within weeks it will join billions of others in a brief emergence to molt, dry, fly, mate, and die.Adult (imago) periodical cicadas. Brood X includes all three species of seventeen-year Periodical Cicadas: Magicicada septendecim, M. cassini, and M. septendecula. All periodical cicadas in the United States are found east of the Great Plains, the lack of trees there prohibiting the expansion of their range further west. Seventeen-year life cycles account for twelve of the fifteen broods of periodical cicadas; the balance live for thirteen years. The range of Brood X includes the lower Susquehanna basin and parts of Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, Ohio, Tennessee, Virginia, West Virginia, and the District of Columbia. (United States Department of Agriculture/Agricultural Research Service image)The flight of periodical cicadas peaks in late-May and June. Shown here is the Swamp Cicada (Neotibicen tibicen), an “annual cicada” that emerges later in the season, peaking yearly during July and August.
The woodlots of the Lower Susquehanna River Watershed won’t be quiet for long. Loud choruses of male periodical cicadas will soon roar through forest and verdant suburbia. They’re looking for love, and they’re gonna die trying to find it. And dozens and dozens of animal species will take advantage of the swarms to feed themselves and their young. Yep, the woods are gonna be a lively place real soon.
Did you say periodical cicadas? We can hardly wait!
