Once upon a time, a great panic spread throughout the lower Susquehanna region. A destructive mob of invaders was overtaking our verdant land and was sure to decimate all in its path. Clad in gray and butternut, they came by the thousands. Flashing their crimson banners, they signaled their arrival at each new waypoint along their route. The Pennsylvania government called upon the populace to heed the call and turn out in defense of the state. Small bands of well-intentioned citizens tried in vain to turn back the progress of the hostiles—none succeeded. But for a cadre of civic-minded elites and some small groups of college professors and their students, few responded to a call to confine the invasion along designated lines of containment. Word spread quickly throughout the valley that farms had been overrun by waves of the merciless intruders. Agrarians reported that their orchards had been stripped; they had lost all of the fruits of their labor. Stories exaggerating the hideous appearance of the approaching aliens struck fear into the faint-of-heart. The growing sentiment among the terror-stricken residents: this horde must be stopped before pestilence is visited upon everyone in the state!
And so, on the evening of June 28, 1863, just three days before the Battle of Gettysburg, the wooden Susquehanna River bridge at Columbia-Wrightsville was set ablaze just as Brigadier General John B. Gordon’s brigade of the invading Army of Northern Virginia approached the span’s west entrance preparing to cross to the eastern shore. Thus, the rebel tide was turned away from the Susquehanna at the point some contend to be the authentic “High-water Mark of the Confederacy”.
During the coming two weeks, peak numbers of migrating Neotropical birds will be passing through the northeastern United States including the lower Susquehanna valley. Hawk watches are staffed and observers are awaiting big flights of Broad-winged Hawks—hoping to see a thousand birds or more in a single day.
Broad-winged hawks feed on rodents, amphibians, and a variety of large insects while on their breeding grounds in the forests of the northern United States and Canada. They depart early, journeying to wintering areas in Central and South America before frost robs them of a reliable food supply.
While migrating, Broad-winged Hawks climb to great altitudes on thermal updrafts and are notoriously difficult to see from ground level. Bright sunny skies with no clouds to serve as a backdrop further complicate a hawk counter’s ability to spot passing birds. Throughout the Lower Susquehanna River Watershed, the coming week promises to be especially challenging for those trying to observe and census the passage of high-flying Broad-winged Hawks. The forecast of hot and humid weather is not so unusual, but the addition of smoke from fires in the western states promises to intensify the haze and create an especially irritating glare for those searching the skies for raptors.
It may seem gloomy for the mid-September flights in 2021, but hawk watchers are hardy types. They know that the birds won’t wait. So if you want to see migrating “Broad-wings” and other species, you’ve got to get out there and look up while they’re passing through.
These hawk watches in the Lower Susquehanna River Watershed are currently staffed by official counters and all welcome visitors:
Rocky Ridge County Park Hawk Watch—3699 Deininger Road off Mount Zion Road (Route 24) northeast of York, Pennsylvania.
Second Mountain Hawk Watch—off Cold Spring Road on the grounds of Fort Indiantown Gap in Lebanon County, Pennsylvania.
Waggoner’s Gap Hawk Watch—where Route 74 crosses Blue Mountain north of Carlisle, Pennsylvania.
—or you can just keep an eye on the sky from wherever you happen to be. And don’t forget to check the trees and shrubs because warbler numbers are peaking too! During recent days…
Common sense tells us that Brood X Periodical Cicada emergence begins in the southern part of the population zone, where the ground temperatures reach 64° first, then progresses to the north as the weather warms. In the forested hills where the lower Piedmont falls away onto the flat landscape of the Atlantic Coastal Plain in Maryland’s Cecil and Harford Counties, the hum of seventeen-year-old insects saturates a listener’s ears from all directions—the climax nears.
With all that food flying around, you just knew something unusual was going to show up to eat it. It’s a buffet. It’s a smorgasbord. It’s free, it’s all-you-can-eat, and it seems, at least for the moment, like it’s going to last forever. You know it’ll draw a crowd.
The Mississippi Kite (Ictiniamississippiensis), a trim long-winged bird of prey, is a Neotropical migrant, an insect-eating friend of the farmer, and, as the name “kite” suggests, a buoyant flier. It experiences no winter—breeding in the southern United States from April to July, then heading to South America for the remainder of the year. Its diet consists mostly of large flying insects including beetles, leafhoppers, grasshoppers, dragonflies, and, you guessed it, cicadas. Mississippi Kites frequently hunt in groups—usually catching and devouring their food while on the wing. Pairs nest in woodlands, swamps, and in urban areas with ample prey. They are well known for harmlessly swooping at people who happen to get too close to their nest.
Mississippi Kites nest regularly as far north as southernmost Virginia. For at least three decades now, non-breeding second-year birds known as immatures have been noted as wanderers in the Mid-Atlantic States, particularly in late May and early June. They are seen annually at Cape May, New Jersey. They are rare, but usually seen at least once every year, along the Piedmont-Atlantic Coastal Plain border in northern Delaware, northeastern Maryland, and/or southeastern Pennsylvania. Then came the Brood X Periodical Cicadas of 2021.
During the last week of May and these first days of June, there have been dozens of sightings of cicada-eating Mississippi Kites in locations along the lower Piedmont slope in Harford and Cecil Counties in Maryland, at “Bucktoe Creek Preserve” in southern Chester County, Pennsylvania, and in and near Newark in New Castle County, Delaware. They are being seen daily right on the lower Susquehanna watershed’s doorstep.
Today, we journeyed just south of Mason’s and Dixon’s Delaware-Maryland-Pennsylvania triangle to White Clay Creek State Park along Route 896 north of Newark, Delaware. Once there, we took a short bicycle ride into a wooded neighborhood across the street in Maryland to search for the Mississippi Kites that have been reported there in recent days.
Will groups of Mississippi Kites develop a taste for our seventeen-year cicadas and move north into the Lower Susquehanna River Watershed? Ah, to be young and a nomad—that’s the life. Wandering on a whim with one goal in mind—food. It could very well be that now’s the time to be on the lookout for Mississippi Kites, especially where Brood X Periodical Cicadas are abundant.
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.
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. cassinii, 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. cassinii 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.
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. cassinii, produce a buzzy chorus that, when comprised of hundreds or thousands of cicadas “singing” in unison, creates, when heard from a distance, 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 the species’ unofficial common name. 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. cassinii, often known as “Cassin’s 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.
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.
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…
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.
If you go out and about to observe Periodical Cicadas, keep an eye open for these species too…
Back in the spring of 2004, members of the Tri-County Conewago Creek Association (T.C.C.C.A.), a non-profit conservation group founded to improve water quality in Conewago Creek and its tributaries in Dauphin, Lancaster, and Lebanon Counties in Pennsylvania, were, in order to better understand the status of the flora and fauna in the watershed, frequently spending their weekends surveying the animal and plant life found in the drainage basin’s forests, streams, and farmlands. This effort identified populations of several species of concern and helped supplement the more formal assessment that was used to determine the placement, scale, and scope of projects needed to reduce nutrient and erosion impairment in the Conewago’s waterways.
These regular outings happened to coincide with the Brood X Periodical Cicada emergence of 2004. Back then, as the record keeper for the T.C.C.C.A.’s weekly survey forays, your editor decided to shade a map of the Conewago Creek Watershed showing where the group’s volunteers encountered choruses of the Brood X cicadas. Fortunately, the map is still in the editor’s pile of stuff, and is reproduced here for you.
A notation on the map (visible just above the cap on the pen) indicates May 16 as the emergence date for the cicadas in 2004—seventeen years ago today.
So why no seventeen-year cicadas yet in 2021? The answer is ground temperature. This year, by mid-April, Brood X Periodical Cicadas were just below the leaves and rocks, ready to break the surface. But a cold month since then has stalled their emergence. A thermometer pushed into the forest soil today showed readings of 60 degrees and less—at least four degrees below the temperature needed to get the nymphs crawling out of the dirt to climb rocks and vegetation where they’ll molt, dry, and take flight.
A warm week ahead with daytime temperatures in the eighties and nighttime lows in the fifties and sixties, instead of in the forties, should get the woodland soils warming. Brood X Periodical Cicadas will be out and about in a jiffy—and you’ll hear all about it.
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.
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.
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.
Let’s take a quiet stroll through the forest to have a look around. The spring awakening is underway and it’s a marvelous thing to behold. You may think it a bit odd, but during this walk we’re not going to spend all of our time gazing up into the trees. Instead, we’re going to investigate the happenings at ground level—life on the forest floor.
There certainly is more to a forest than the living trees. If you’re hiking through a grove of timber getting snared in a maze of prickly Multiflora Rose (Rosa multiflora) and seeing little else but maybe a wild ungulate or two, then you’re in a has-been forest. Logging, firewood collection, fragmentation, and other man-made disturbances inside and near forests take a collective toll on their composition, eventually turning them to mere woodlots. Go enjoy the forests of the lower Susquehanna valley while you still can. And remember to do it gently; we’re losing quality as well as quantity right now—so tread softly.
Second Mountain Hawk Watch is located on a ridge top along the northern edge of the Fort Indiantown Gap Military Reservation and the southern edge of State Game Lands 211 in Lebanon County, Pennsylvania. The valley on the north side of the ridge, also known as St. Anthony’s Wilderness, is drained to the Susquehanna by Stony Creek. The valley to the south is drained toward the river by Indiantown Run, a tributary of Swatara Creek.
The hawk watch is able to operate at this prime location for observing the autumn migration of birds, butterflies, dragonflies, and bats through the courtesy of the Pennsylvania Game Commission and the Garrison Commander at Fort Indiantown Gap. The Second Mountain Hawk Watch Association is a non-profit organization that staffs the count site daily throughout the season and reports data to the North American Hawk Watch Association (posted daily at hawkcount.org).
Today, Second Mountain Hawk Watch was populated by observers who enjoyed today’s break in the rainy weather with a visit to the lookout to see what birds might be on the move. All were anxiously awaiting a big flight of Broad-winged Hawks, a forest-dwelling Neotropical species that often travels back to its wintering grounds in groups exceeding one hundred birds. Each autumn, many inland hawk watches in the northeast experience at least one day in mid-September with a Broad-winged Hawk count exceeding 1,000 birds. They are an early-season migrant and today’s southeast winds ahead of the remnants of Hurricane Florence (currently in the Carolinas) could push southwest-heading “Broad-wings” out of the Piedmont Province and into the Ridge and Valley Province for a pass by the Second Mountain lookout.
The flight turned out to be steady through the day with over three hundred Broad-winged Hawks sighted. The largest group consisted of several dozen birds. We would hope there are probably many more yet to come after the Florence rains pass through the northeast and out to sea by mid-week. Also seen today were Bald Eagles, Ospreys, American Kestrels, and a migrating Red-headed Woodpecker.
Migrating insects included Monarch butterflies, and the three commonest species of migratory dragonflies: Wandering Glider, Black Saddlebags, and Common Green Darner. The Common Green Darners swarmed the lookout by the dozens late in the afternoon and attracted a couple of American Kestrels, which had apparently set down from a day of migration. American Kestrels and Broad-winged Hawks feed upon dragonflies and often migrate in tandem with them for at least a portion of their journey.
Still later, as the last of the Broad-winged Hawks descended from great heights and began passing by just above the trees looking for a place to settle down, a most unwelcome visitor arrived at the lookout. It glided in from the St. Anthony’s Wilderness side of the ridge on showy crimson-red wings, then became nearly indiscernible from gray tree bark when it landed on a limb. It was the dreaded and potentially invasive Spotted Lanternfly (Lycorma delicatula). This large leafhopper is native to Asia and was first discovered in North America in the Oley Valley of eastern Berks County, Pennsylvania in 2014. The larval stage is exceptionally damaging to cultivated grape and orchard crops. It poses a threat to forest trees as well. Despite efforts to contain the species through quarantine and other methods, it’s obviously spreading quickly. Here on the Second Mountain lookout, we know that wind has a huge influence on the movement of birds and insects. The east and southeast winds we’ve experienced for nearly a week may be carrying Spotted Lanternflies well out of their most recent range and into the forests of the Ridge and Valley Province. We do know for certain that the Spotted Lanternfly has found its way into the Lower Susquehanna River Watershed.
It’s sprayed with herbicides. It’s mowed and mangled. It’s ground to shreds with noisy weed-trimmers. It’s scorned and maligned. It’s been targeted for elimination by some governments because it’s undesirable and “noxious”. And it has that four letter word in its name which dooms the fate of any plant that possesses it. It’s the Common Milkweed, and it’s the center of activity in my garden at this time of year. Yep, I said milk-WEED.
Now, you need to understand that my garden is small—less than 2,500 square feet. There is no lawn, and there will be no lawn. I’ll have nothing to do with the lawn nonsense. Those of you who know me, know that the lawn, or anything that looks like lawn, and I are through.
Anyway, most of the plants in the garden are native species. There are trees, numerous shrubs, some water features with aquatic plants, and filling the sunny margins is a mix of native grassland plants including Common Milkweed. The unusually wet growing season in 2018 has been very kind to these plants. They are still very green and lush. And the animals that rely on them are having a banner year. Have a look…
I’ve planted a variety of native grassland species to help support the milkweed structurally and to provide a more complete habitat for Monarch butterflies and other native insects. This year, these plants are exceptionally colorful for late-August due to the abundance of rain. The warm season grasses shown below are the four primary species found in the American tall-grass prairies and elsewhere.
There was Monarch activity in the garden today like I’ve never seen before—and it revolved around milkweed and the companion plants.
Eaton, Eric R., and Kenn Kaufman. 2007. Kaufman Field Guide to Insects of North America. Houghton Mifflin Company. New York.
There’s something frightening going on down there. In the sand, beneath the plants on the shoreline, there’s a pile of soil next to a hole it’s been digging. Now, it’s dragging something toward the tunnel it made. What does it have? Is that alive?
We know how the system works, the food chain that is. The small stuff is eaten by the progressively bigger things, and there are fewer of the latter than there are of the former, thus the whole network keeps operating long-term. Some things chew plants, others devour animals whole or in part, and then there are those, like us, that do both. In the natural ecosystem, predators keep the numerous little critters from getting out of control and decimating certain other plant or animal populations and wrecking the whole business. When man brings an invasive and potentially destructive species to a new area, occasionally we’re fortunate enough to have a native species adapt and begin to keep the invader under control by eating it. It maintains the balance. It’s easy enough to understand.
Late summer days are marked by a change in the sounds coming from the forests surrounding the falls. For birds, breeding season is ending, so the males cease their chorus of songs and insects take over the musical duties. The buzzing of the male “Annual Cicada” (Tibicen) is the most familiar. The female cicada lays its eggs in the twigs of trees. After hatching, the nymphs drop to the ground and burrow to live and feed along tree roots for the next two to five years. A dry exoskeleton clinging to a tree trunk is evidence that a nymph has emerged from the soil and flown away as an adult. There are adult Annual Cicadas present every year.
For the adult cicada, there is danger. It looks like an enormous bee. It’s a Cicada Killer (Specius speciosus) wasp, and it will latch onto a cicada and begin stinging while both are in flight. The stings soon paralyze the screeching panicked cicada. The Cicada Killer then begins the task of airlifting and/or dragging its victim to the lair it has prepared. The cicada is placed in one of more than a dozen cells in the tunnel complex where it will serve as food for the wasp’s larvae. The wasp lays an egg on the cicada, then leaves and pushes the hole closed. The egg hatches in a several days and the larval grub is on its own to feast upon the hapless cicada.
Other species in the Solitary Wasp family (Sphecidae) have similar life cycles using specific prey which they incapacitate to serve as sustenance for their larvae.
The Solitary Wasps are an important control on the populations of their respective prey. Additionally, the wasp’s bizarre life cycle ensures a greater survival rate for its own offspring by providing sufficient food for each of its progeny before the egg beginning its life is ever put in place. It’s complete family planning.
The cicadas reproduce quickly and, as a species, seem to endure the assault by Cicada Killers, birds, and other predators. The Periodical Cicadas (Magicicada), with adult flights occurring as a massive swarm of an entire population every thirteen or seventeen years, survive as species by providing predators with so ample a supply of food that most of the adults go unmolested to complete reproduction. Stay tuned, 2021 is due to be the next Periodical Cicada year in the vicinity of Conewago Falls.
Eaton, Eric R., and Kenn Kaufman. 2007. Kaufman Field Guide to Insects of North America. Houghton Mifflin Company. New York.