While the heat and humidity of early summer blankets the region, Brood XIV Periodical Cicadas are wrapping up their courtship and breeding cycle for 2025. We’ve spent the past week visiting additional sites in and near the Lower Susquehanna River Watershed where their emergence is evident.
We begin in York County just to the west of the river and Conewago Falls in mostly forested terrain located just southeast of Gifford Pinchot State Park. Within this area, often called the Conewago Hills, a very localized population of cicadas could be heard in the woodlands surrounding the scattered homes along Bull Road. Despite the dominant drone of an abundance of singing Pharaoh Periodical Cicadas, we were able to hear and record the courtship song of a small number of the rare Little Seventeen-year Cicadas. Their lawn sprinkler-like pulsating songs help mate-seeking males penetrate the otherwise overwhelming chorus of the Pharaoh cicadas in the area.
The Little Seventeen-year Cicada’s (Magicicada septendecula) thorax is black between the eye and the origin of the wings. It is the rarest of the three species of seventeen-year cicadas.The underside of male (left) and female (right) Little Seventeen-year Cicadas shows narrow orange edges on the abdominal segments.
From the Conewago Hills we moved northwest into the section of southern Cumberland County known as South Mountain. Here, Pharaoh Periodical Cicadas were widespread in ridgetop forests along the Appalachian Trail, particularly in the area extending from Long Mountain in the east through Mount Holly to forests south of King’s Gap Environmental Education Center in the west.
Pharaoh Periodical Cicadas along the Appalachian Trail on South Mountain, Cumberland County, Pennsylvania. Like the cicadas we visited last week on the east side of the Susquehanna, this population is surviving on lands with a history of timber harvest and charcoal production to fuel nearby iron furnaces during the nineteenth century.
While on South Mountain, we opted for a side trip into the neighboring Potomac watershed of Frederick County, Maryland, where these hills ascend to greater altitude and are known as the Blue Ridge Mountains, a name that sticks with them all the way through Shenandoah National Park, the Great Smoky Mountains, and to their southern terminus in northwestern Georgia. We found a fragmented emergence of Pharaoh Periodical Cicadas atop the Catoctin Mountain section of the Blue Ridge just above the remains of Catoctin Furnace, again on lands that had been timbered to make charcoal to fuel iron production prior to their protection as vast expanses of forest.
A Pharaoh Periodical Cicada on Catoctin Mountain near Catoctin Furnace south of Thurmont, Maryland. These cicadas are not part of a Brood XIV emergence, but are instead a population of Brood X (2021) stragglers.A female Brood X Pharaoh Periodical Cicada straggler on Catoctin Mountain. The website “cicadamania.com” notes, “Experts (Gaye Williams, State Entomologist of Maryland, John Cooley of UCONN) have confirmed that there will be no Brood XIV cicadas for Maryland.”
Back in Pennsylvania, we’re on our way to the watersheds of the northernmost tributaries of the lower Susquehanna’s largest tributary, the Juniata River. There, we found Brood XIV cicadas more widespread and in larger numbers than occurred at previous sites. Both Pharaoh and Cassin’s Periodical Cicadas were seen and heard along Jack’s Mountain and the Kishacoquillas Creek north of Lewistown/Burnham in Mifflin County. To the north of the Kishacoquillas Valley and Stone Mountain in northernmost Huntingdon County, the choruses of the two species were again widespread, particularly along the forest edges in Greenwood Furnace State Park, Rothrock State Forest, and adjacent areas of the Standing Stone Creek watershed.
A view of the sound-generating tymbal on a male Pharaoh Periodical Cicada at Greenwood Furnace State Park. Rapid vibration of the tymbals by a set of specialized muscles generates the distinctive calls and courtship songs of the various cicada species. When handled, these tymbals can produce a harsh “panic call”. This distress sound could startle a would-be predator and provide the cicada with an opportunity to escape.The sound organs comprised of ribbed tymbals and specialized muscles on the male Cassin’s Periodical Cicada generate a “panic call” as well as the distinctive calls and songs used to penetrate the droning choruses of the more numerous Pharaoh Periodical Cicadas with which it shares a seventeen-year flight.Using their specialized sound organs, Cassin’s Periodical Cicadas generate a courtship song that usually includes buzzy phrases and ticking notes (first sound clip). The buzzing and ticking helps the male Cassin’s cicada penetrate the songs of the more numerous Pharaoh Periodical Cicadas in the area (second sound clip). When synchronized into a chorus that surges in volume, the songs of Cassin’s Periodical Cicadas can overcome the overwhelming drone of the nearby Pharaoh cicadas (third sound clip).After mating and before the lives of these seventeen-year cicadas draw to a close, the females need to deposit their fertilized eggs into the small end twigs of suitable trees. On a small hawthorn tree (Cretaegus species) along the edge of the forest at Greenwood Furnace State Park, this Pharaoh Periodical Cicada is using her ovipositor to make a slit in a twig and place her eggs.Simultaneously on the same little hawthorn tree, this female Cassin’s Periodical Cicada is depositing her fertilized eggs.
Within the last 48 hours, we visited one last location in the Lower Susquehanna River Watershed where Brood XIV Periodical Cicadas have emerged during 2025. In the anthracite coal country of Northumberland County, a flight of Pharaoh Periodical Cicadas is nearing its end. We found them to be quite abundant in forested areas of Zerbe Run between Big and Little Mountains around Trevorton and on the wooded slopes of Mahanoy Mountain south of nearby Shamokin. Line Mountain south of Gowen City had a substantial emergence as well.
A Brood XIV Pharaoh Periodical Cicada near Zerbe Run west of Trevorton, Northumberland County, Pennsylvania. The following sound clip features the fading chorus of these cicadas and some of the nesting birds that may actually be preying upon them: Yellow-billed Cuckoo, Red-eyed Vireo, and Northern Cardinal. Brown leaves reveal the end twigs where female Pharaoh Periodical Cicadas have deposited eggs during the last several weeks. During July, the larvae will hatch and drop to the ground to start a new generation of Brood XIV cicadas. As subterranean nymphs, they’ll spend the coming seventeen years feeding on small amounts of xylem sap from tree roots. In 2042, during the next Brood XIV emergence, these nymphs will come to the surface and take flight as adults.Evidence of egg deposition among foliage on Line Mountain at State Game Lands 229.Accumulations of deceased Pharaoh Periodical Cicadas on Line Mountain.Fallen cicadas that show any sign of life are being snatched up by predators such as this Eastern Gartersnake (Thamnophis sirtalis sirtalis). Meanwhile, the remainder of the biomass is picked apart by scavengers or is left to reducers for breakdown into fertilizer and organic matter for the forest. Nothing goes to waste.
To chart our travels, we’ve put together this map plotting the occurrence of significant flights of Periodical Cicadas during the 2025 emergence. Unlike the more densely distributed Brood X cicadas of 2021, the range of Brood XIV insects is noticeably fragmented, even in areas that are forested. We found it interesting how frequently we found Brood XIV cicadas on lands used as sources of lumber to make charcoal for fueling nineteenth-century iron furnace operations.
The furnaces at Greenwood Furnace State Park required the daily cutting of one acre of timber to make enough charcoal to fuel the iron-making process. Did keeping thousands of acres in various stages of forest succession to supply the charcoal needs of these operations aid the survival of earlier generations of Periodical Cicadas on these lands? Or, after the furnaces converted to coal for fuel, did the preservation of many of these parcels as state, federal, and private forests allow the cicadas to find refuge from the widespread impacts of agriculture and expanding urbanization in adjacent lands? Maybe it’s a little of both. We always bear in mind that annual insects and other animals are more than one hundred generations removed from the negative or positive impacts of the early years of the industrial age, but only about ten generations have passed since populations of seventeen-year Periodical Cicadas were directly influenced by these factors. What do you think?
Well, that’s a wrap. Please don’t forget to check out our new Cicadas page by clicking the “Cicadas” tab at the top of this page. Soon after the Periodical Cicadas are gone, the annual cicadas will be emerging and our page can help you identify the five species found regularly in the lower Susquehanna valley. ‘Til next time, keep buzzing!
Here are some sights and sounds from the ongoing emergence of Brood XIV Periodical Cicadas in the Lower Susquehanna River Watershed.
We begin in the easternmost spur of the lower basin where a sizeable emergence of cicadas can be seen and heard in the woodlands surrounding the headwaters of the Conestoga River in Berks County north of Morgantown. This flight extends east into Chester County and the French Creek drainage of the Schuylkill River watershed on State Game Lands 43 north of Elverson and consists of Pharaoh Periodical Cicadas (Magicicada septendecim), the most common species among 17-year broods.
A Brood XIV Pharaoh Periodical Cicada at State Game Lands 43 identified by the red bar extending from the eye to the wing root.The underside of the abdomen on a male Pharaoh Periodical Cicada showing the wide orange bars on each segment.Exuvia of a recently emerged Pharaoh Periodical Cicada.Soon after landing on a perch, a male Pharaoh Periodical Cicada will usually announce his presence by singing. It’s an attempt to quickly attract potential mates that may be in the vicinity.Pharaoh Periodical Cicadas ascending the branches of an oak.Gatherings of thousands of singing male Pharaoh Periodical Cicadas create a distinctive droning chorus.A receptive female will make a click sound with her wings to summon a suitable singing male for mating.While usually occurring in the safety of the trees, the breeding frenzy can spill over onto the ground where we happened to find this copulating pair.After mating, female cicadas make slits in the end twigs of selected trees into which they lay their eggs. The process of egg-laying and larval emergence will usually wilt and kill end growth on the affected branches, causing little harm to healthy trees. It’s similar to the trim you might give to a bonsai plant to keep it stout and sturdy.How long do Periodical Cicadas live? Well, by last week, we were already finding dead specimens by the thousands. Most of them had already completed their breeding cycle and planted the seeds for a new generation of Brood XIV cicadas.A deceased Pharaoh Periodical Cicada at the Fire Tower Parking Area at French Creek State Park. This specimen and a chorus on the hill’s forested south slope were the northeastern-most evidence of Brood XIV Periodical Cicadas we could find for the population cluster in portions of Berks, Chester, and Lancaster Counties around Morgantown.The abundance of Pharaoh Periodical Cicadas on State Game Lands 43 in Chester County has attracted numerous raptors, particularly wandering one-year-old birds that aren’t quite mature enough to nest. Among the sightings have been Red-tailed Hawks, Red-shouldered Hawks, Broad-winged Hawks, and at least three Mississippi Kites, a rarity on the Piedmont this far inland from the coastal plain. (See the post from June 5, 2021, for details on the occurrence of Mississippi Kites in northernmost Delaware during the Brood X emergence.)
From Route 82 north of Elverson to the west through the forested areas along Route 10 north of Morgantown and the Pennsylvania Turnpike, we found an abundance of Cassin’s Periodical Cicadas (Magicicada cassini) calling among the Pharaohs. This mix of Pharaoh and Cassin’s Periodical Cicadas extends west along the north side of the turnpike into Lancaster County and State Game Lands 52 on Black Creek north of Churchtown.
A Brood XIV Cassin’s Periodical Cicada at State Game Lands 52 is identified by the all-black margin between the eye and the wing root and……the black underside of the abdomen with no orange stripes.To penetrate the sounds of the more common Pharaoh Periodical Cicadas, male Cassin’s Periodical Cicadas gather in large concentrations to generate a loud, oscillating chorus. Its surging volume will usually exceed that of the Pharaohs singing in the vicinity.Mated Cassin’s Periodical Cicadas copulating at State Game Lands 52.The underside of copulating Cassin’s Periodical Cicadas.A pair of Cassin’s Periodical Cicadas at state Game Lands 52 in Lancaster County.
Further west in Cornwall, Lebanon County, a Brood XIV emergence can be found on similar forested terrain: the Triassic hills of the Newark Basin—rich in iron ore and renowned for furnace operations during the eighteenth and nineteenth centuries. Pharaoh Periodical Cicadas were the only species heard among this population that extends from Route 72 east through the woodlands along Route 322 into the northern edge of State Game Lands 156 in Lancaster County.
On the west side of the Susquehanna, yet another isolated population of Brood XIV Periodical Cicadas can be found in Perry County, just south of Duncannon on State Game Lands 170 on the slopes of “Cove Mountain”, the canoe-shaped convergence of the western termini of Peters and Second Mountains.
Pharaoh Periodical Cicadas dominated this Perry County chorus,…
…but we did detect at least one Cassin’s Cicada trying to find a mate.
A solitary Cassin’s Periodical Cicada issues a lonely song of short buzzes and ticking notes on State Game Lands 170. Fragmented populations, especially those that are only able to fly and increase their distribution every 17 years, often have a challenging time expanding and reuniting their disjointed ranges.
Not to say they aren’t present, but we have yet to detect the rarest species, Magicicada septendecula, the “Little Seventeen-year Cicada”, among the various populations of Brood XIV Periodical Cicadas emerging in the lower Susquehanna valley. For the coming two weeks or so until this brood is gone for another 17 years, the search continues.
For more on both annual and periodical cicada species in the Lower Susquehanna River Watershed, be sure to click the “Cicadas” tab at the top of this page!
The emergence of Brood X Periodical Cicadas is now in full swing. If you visit a forested area, you may hear the distant drone of very large concentrations of one or more of the three species that make up the Brood X event. The increasing volume of a chorus tends to attract exponentially greater numbers of male cicadas from within an expanding radius, causing a swarm to grow larger and louder—attracting more and more females to the breeding site.
Holes in the ground where emerging Brood X Periodical Cicadas have come to the surface.Having ascended the trunk of this Eastern White Pine after emerging from the soil, massive numbers of periodical cicadas have left behind hundreds of opaque exuviae. The exuvia is the exoskeletal remains of the cicada’s final molt from a nymph into a flying adult.A freshly molted Magicicada cassini periodical cicada.
Each periodical cicada species has a distinctive song. This song concentrates males of the same species at breeding sites—then draws in an abundance of females of the same species to complete the mating process. Large gatherings of periodical cicadas can include all three species, but a close look at swarms on State Game Lands 145 in Lebanon County and State Game Lands 46 (Middle Creek Wildlife Management Area) in Lancaster County during recent days found marked separation by two of the three. Most swarms were dominated by Magicicada septendecim, the largest, most widespread, and most common species. However, nearly mono-specific swarms of M. cassini, the second most numerous species, were found as well. An exceptionally large one was northwest of the village of Colebrook on State Game Lands 145. It was isolated by a tenth of a mile or more from numerous large gatherings of M. septendecim cicadas in the vicinity. These M. cassini cicadas, with a chorus so loud that it outdistanced the songs made by the nearby swarms of M. septendecim, seized the opportunity to separate both audibly and physically from the more dominant species, thus providing better likelihood of maximizing their breeding success.
Some of the tens of thousands of M. cassini periodical cicadas in a concentration on State Game Lands 145 northwest of Colebrook in Lebanon County, Pennsylvania. This swarm occupied deciduous and evergreen trees on several acres of a south-facing hillside. To provide protection from predators and assure the chance of finding a mate “in the crowd”, lesser numbers of this and the rarer species, Magicicada septendecula, would need to merge into the swarms of the abundant M. septendecim periodical cicadas to breed.
The process of identifying periodical cicadas is best begun by listening to their choruses, songs, and calls. After all, the sounds of cicadas will lead one to the locations where they are most abundant. The two most common species, M. septendecim and M. cassini, produce a buzzy chorus that, when consisting of hundreds or thousands of cicadas “singing” in unison, creates a droning wail that can carry for a quarter of a mile or more. It’s a surreal humming sound that may remind one of a space ship from a science fiction film.
Listen to the songs of individual cicadas at close range and you’ll hear a difference between the widespread M. septendecim “Pharaoh Periodical Cicada” and the other two species. M. septendecim‘s song is often characterized as a drawn out version of the word “Pharaoh”, hence one of the species’ common names (another is “Seventeen-year Locust”). As part of their courtship ritual, “Pharaoh Periodical Cicadas” sometimes make a purring or cooing sound, which is often extended to sound like kee-ow, then sometimes revved up further to pha-raoh. M. cassini, often known as “Cassin’s Periodical Cicada” or “Dwarf Periodical Cicada”, and the least common species, M. septendecula, often make scratchy clicking or rattling calls as a lead-in to their song. Most observers will find little difficulty locating the widespread M. septendecim “Pharaoh Periodical Cicada” by sound, so listening for something different—the clicking call—is an easy way to zero in on the two less common species.
To penetrate the droning choruses of large numbers of “Pharaoh” and/or “Cassin’s Periodical Cicadas”, sparingly distributed M. septendecula cicadas have a noise-penetrating song consisting of a series of quick raspy notes with a staccato rhythm reminiscent of a pulsating lawn sprinkler. It can often be differentiated by a listener even in the presence of a roaring chorus of one or both of the commoner species. However, a word of caution is due. To call in others of their kind, “Cassin’s Periodical Cicadas” can produce a courtship song similar to that of M. septendecula so that they too can penetrate the choruses of the enormous numbers of “Pharaoh Periodical Cicadas” that concentrate in many areas. To play it safe, it’s best to have a good look at the cicadas you’re trying to identify.
M. cassini periodical cicadas “singing” from a treetop at Colebrook, Lebanon County, Pennsylvania. Clicking phrases are sure sign of the presence of this species and/or M. septendecula, the least likely of the three species to be encountered. When in close proximity to a swarm, a listener will often notice the rising and falling volume of a chorus in a cycle that repeats every few seconds, an effect caused by cicadas attempting to synchronize their songs in a harmony with others in the group. When courtship and mating is complete, female periodical cicadas will begin laying eggs in slits made in fresh new growth at the ends of branches on deciduous trees like the one seen here.
Visually identifying Brood X Periodical Cicadas to the species level is best done by looking for two key field marks—first, the presence or absence of orange between the eye and the root of the wings, and second, the presence or absence of orange bands on the underside of the abdomen. Seeing these field marks clearly requires in-hand examination of the cicada in question.
Observing a perched Brood X Periodical Cicada can sometimes provide a view of the key field marks needed for identification of the species. On the M. septendecim “Pharaoh Periodical Cicada” seen here, the orange patch between the eye and wing root and the orange bands on the underside of the abdomen are visible.The abdomen of this perched M. cassini “Cassin’s Periodical Cicada” appears, when viewed through the wings, to have orange bands. But, examination in hand would show an all-black abdomen with glossy surfaces shining in the sunlight. For accuracy, the up-close-and-personal look is necessary.In the hand, cicadas can be better studied for key field marks. M. septendecim (top) is larger than M. cassini (bottom) and M. septendecula, but the difference is not always apparent, particularly when a direct comparison cannot be made.
To reliably separate Brood X Periodical Cicadas by species, it is necessary to get a closeup view of the section of the thorax between the eye and the root (insertion) of the wings, plus a look at the underside of the abdomen. Here’s what you’ll see…
M. septendecim has an orange patch between the eye and the root of the wings.The underside of M. septendecim’s abdomen has orange bands or stripes along the trailing edge of each segment. The width of the bands can vary, but is typically wider on males (left) than on females (right).
Magicicada cassini—“Cassin’s Periodical Cicada”
The thorax of M. cassini is black between the eye and the wing insertion.In both the male (left) and female (right), the underside of M. cassini’s abdomen is all black without orange bands or stripes.
Magicicada septendecula
M. septendecula’s thorax is black between the eye and root of the wings.The underside of M. septendecula’s abdomen has narrow orange bands or stripes along the trailing edge of each segment. The width of the bands can differ. Those of this male (left) are minimal and the bands on this female (right) are near the maximum for the species.
There you have it. Get out and take a closer look at the Brood X Periodical Cicadas near you.
The abundant and widespread “Pharaoh Periodical Cicada” (M. septendecim).It’ll all be over before long. Accumulating remains of M. cassini “Cassin’s Periodical Cicadas” beneath an Eastern White Pine at the site of the Colebrook State Game Lands swarm.
The Magi have arrived. Emanating from the shadows of a nearby forest, you may hear the endless drone of what sounds like an extraterrestrial craft. Then you get your first look at those beady red eyes set against a full suit of black armor—out of this world. The Magicicada are here at last.
This exuvia, the leftover from a cicada’s final molt, tells us they are here.A Brood X Periodical Cicada soon after emergence and final molt.Not to worry, cicadas are harmless and docile when handled. This is Magicicada septendecim, the largest and most common of our three species of Brood X seventeen-year cicadas. They are currently emerging along south-facing borders of forests and wooded parks and lawns.Magicicada septendecim can be recognized by the orange on the thorax behind each eye and in front of the wing insertions. The smaller M. cassini and M. septendecula have no orange coloration between the eye and wing.Magicicada septendecim (seen here) has broad orange stripes on the abdomen. M. cassini has an all black abdomen and M. septendecula, the rarest species, has narrow well-defined orange stripes.
If you go out and about to observe periodical cicadas, keep an eye open for these species too…
Spotted Lanternflies, one of our most dreaded invasive species, have hatched. These tiny nymphs about 5 millimetres in length were found feeding on a Virginia Creeper (Parthenocissus quinquefolia), a native vine in the grape family (Vitaceae).Deer Ticks, also known as Black-legged Ticks, are hanging around on vegetation of all kinds looking to hitch a ride on a suitable host. Don’t let it be you. This adult female, less than 5 millimetres in length, was washed loose during an after-hike shower.
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!
