This Week’s Enormous Diurnal Flights

For the past several weeks, we’ve given you a look at the fallout of Neotropical songbirds on mornings following significant nocturnal flights of southbound migrants.  Now let’s examine the diurnal (daytime) flights that have developed in recent days over parts of the lower Susquehanna basin and adjacent regions.

For those observing diurnal migrants, particularly at raptor-counting stations, the third week of September is prime time for large flights of tropics-bound Broad-winged Hawks.  Winds from easterly directions during this year’s movements kept the greatest concentrations of these birds in the Ridge and Valley Province and upper areas of the Piedmont as they transited our region along a southwesterly heading.  Counts topped 1,000 birds or more on at least one day at each of these lookouts during the past seven days.  Meanwhile at hawk watches along the Piedmont/Atlantic Coastal Plain border, where flights topped 10,000 or more birds on the best days last fall, observers struggled to see 100 Broad-winged Hawks in a single day.

Broad-winged Hawks
Dozens of migrating Broad-winged Hawks during a morning liftoff to the north of Blue Mountain.

Among the challenges counters faced while enumerating migratory Broad-winged Hawks this week was the often clear blue skies, a glaring sun, and the high altitude at which these raptors fly during the mid-day hours.

"Kettling" Broad-winged Hawks
Large numbers of Broad-winged Hawks climbing on a thermal updraft to gain altitude can become increasingly difficult to spot in a clear blue sky.
"Kettling" Broad-winged Hawks
Higher and higher they go until they practically disappear from view.
Broad-winged Hawks
Cloud cover can help make locating really high-flying birds a bit easier, but they can sometimes climb into the lower portion of the cloud and vanish.

Another factor complicating the hawk counters’ tasks this week, particularly west of the Susquehanna River, was the widespread presence of another group of diurnal fliers.

Blue Jay
Was it the migratory Blue Jays that are beginning to move through the area?   No.
Sharp-shinned Hawk
Was it the increasing numbers of Sharp-shinned Hawks and other raptors?  No.
Hawkwatchers Scanning the Skies
So what was it that complicated the hawkwatchers’ efforts to find high-flying Broad-winged Hawks during this week’s flights?
Spotted Lanternfly
Is it a bird?  Is it a plane?  No.  And it’s nobody’s superhero either.  It’s the non-native Spotted Lanternfly and it is now very numerous west of the Susquehanna and common enough to the east to make even experienced observers take a second look while scanning the skies for Broad-winged Hawks and other migrating raptors.  Just how many do raptor counters have to contend with?  Even where these invasive insects have become less populous in the lower Susquehanna valley, hundreds still fill the skies above forest clearings around hawk-counting stations including Waggoner’s Gap, Second Mountain, and Rocky Ridge County Park.
Spotted Lanternflies on Radar
Spotted Lanternfly populations explode with great vigor as they colonize areas with plenty of tender new growth on native, non-native, and cultivated shrubs, trees, and vines.  Earlier this week, National Weather Service Doppler Radar in Pittsburgh, Pennsylvania, captured enormous mid-afternoon flights of Spotted Lanternflies in recently invaded areas of southwestern Pennsylvania and eastern Ohio.  (NOAA/National Weather Service Doppler Radar image)
Spotted Lanternflies on Radar
A base velocity image consisting primarily of Spotted Lanternflies in southwestern Pennsylvania and eastern Ohio.  (NOAA/National Weather Service Doppler Radar image)

As the Broad-winged Hawk migration draws to a close during the coming ten days, the occurrence of the one dozen other migratory diurnal raptors will be on the upswing.  They generally fly at lower altitudes, often relying upon wind updrafts on the ridges for lift instead of high-rising thermal updrafts.  They therefore present better observation opportunities for visitors at hawk watch lookouts and are less frequently confused with high-flying Spotted Lanternflies.

Merlin
A Merlin seen earlier this week migrating through the Lower Susquehanna River Watershed.  The numbers of migrating Merlins and other falcons will peak sometime in coming weeks.

A Rare Find Among the Migrants at Second Mountain Hawk Watch

Yesterday morning’s fallout of hundreds of nocturnally migrating birds was followed overnight by the influx of one hundred or more new arrivals atop Second Mountain in Lebanon County, Pennsylvania.  Visitors to the forest clearing used as a hawk watch lookout were treated to the antics of these colorful Neotropical species and more…

Red-eyed Vireo
…Red-eyed Vireo,…
A Great Crested Flycatcher.
…Great Crested Flycatcher,…
Least Flycatcher
…Least Flycatcher,…
A Northern Parula.
…Northern Parula,…
Juvenile Northern Paula
…juvenile Northern Paula,…
Nashville Warblers
…and quarrelsome Nashville Warblers.

These night-flying warblers, vireos, and flycatchers did again provide a thrilling show during the hours after sunrise, but today’s rarity passed through among the hundreds of migrating diurnal raptors—the tropics-bound Broad-winged Hawks—that made their way down the ridges of the lower Susquehanna valley this afternoon.

"Kettling" Broad-winged Hawks
A “kettle” of Broad-winged Hawks climbing on a thermal updraft above Second Mountain Hawk Watch.
Broad-winged Hawks
After gaining altitude, Broad-winged Hawks glide away toward the southwest in search of the next thermal updraft upon which they will rise to continue their journey to Texas, Mexico, and beyond.  Over three hundred of these raptors were counted as they passed the Second Mountain lookout today.
"Kettling" Broad-winged Hawks
Another “kettling” flock of migrating Broad-winged Hawks above Second Mountain.
Light-morph and dark-morph Broad-winged Hawks
A closer look reveals something unusual.  While the Broad-winged Hawk at the bottom center of the image displays the typical light-morph plumage, the bird in the upper left appears to be a dark-morph Broad-winged Hawk, a rarity in the eastern United States.
Dark-morph Broad-winged Hawk
A zoomed-in view of the probable dark-morph Broad-winged Hawk seen over Second Mountain this afternoon.  Populations of these variants nest in areas of central and western Canada.

The peak of the autumn Broad-winged Hawk migration will likely occur during the coming two weeks with many counting stations tallying more than one thousand birds on the best of days.  Visit one of these prominent lookout points so that you too can witness this amazing spectacle.  Click the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab at the top of this page to find a hawk watch near you!

This Week’s Review of the Morning Fallouts

Clear, cool nights have provided ideal flight conditions for nocturnal Neotropical migrants and other southbound birds throughout the week.  Fix yourself a drink and a little snack, then sit down and enjoy this set of photographs that includes just some of the species we found during sunrise feeding frenzies atop several of the Lower Susquehanna River Watershed’s ridges.  Hurry up, because here they come…

Black-throated Green Warbler
A Black-throated Green Warbler.
Black-throated Green Warbler
The Black-throated Green Warbler was perhaps the most frequently identified treetop warbler during the most recent four mornings.
Black-throated Green Warbler
A Black-throated Green Warbler with a unique variation in the crown plumage.
Blackburnian Warbler
The Blackburnian Warbler was another plentiful species.
Cape May Warblers
Cape May Warblers have an affinity for conifers like this Eastern White Pine.
Cape May Warbler
But when traveling in mixed flocks with other migrants, Cape May Warblers can also be found feeding in the crown foliage of deciduous trees.
Tennessee Warbler
This adult Tennessee Warbler appears to be adorned in a very worn set of plumage…
Tennessee Warbler
…and its traveling companion looks like it’s overdue for a new set of feathers as well.
Nashville Warbler
Like the Tennessee Warbler, the Nashville Warbler was common among mixed flocks.
Nashville Warbler
A Nashville Warbler atop a Black Cherry.
Chestnut-sided Warbler
This Chestnut-sided Warbler was one of several found among the more common species of migrants.
Chestnut-sided Warbler
A Chestnut-sided Warbler.
Chestnut-sided Warbler
We were lucky enough to spot this male Chestnut-sided Warbler sporting his namesake flank feathers.
 Black-and-white Warbler
A Black-and-white Warbler uses its nuthatch-like feeding behavior to search the tree bark for edible invertebrates.
Common Yellowthroat
To see the Common Yellowthroat, one must cease looking upward into the high canopy and instead give the aching neck a rest by peering into the low vegetation at the forest edge.
Magnolia Warbler
While checking the low growth, keep an eye open for other migrants among the shrubs and tangles. This Magnolia Warbler glows in the rays of a rising sun as it searches for a meal after a long night of travel.
House Wren
Here we found a perky little House Wren.
Eastern Wood-Pewee
Back in the middle and upper reaches of the trees, we find what has been by far the most numerous of the flycatchers seen during our visits to fallout sunrises.  Eastern Wood-Pewees are appearing in very good numbers and can be seen quarreling and battling for hunting perches from which they are ambushing flying insects.
 Eastern Wood-Pewee
An Eastern Wood-Pewee fiercely defending its hunting perch.
Eastern Wood-Pewee
An Eastern Wood-Pewee.
Least Flycatcher
The numbers of migrating Least Flycatchers and other members of the genus Empidonax may be reaching their seasonal peak this week.
Scarlet Tanagers
Scarlet Tanagers are currently a common find following nocturnal flights.
Scarlet Tanager
A Scarlet Tanager peers down from the top of a Red Maple.
Rose-breasted Grosbeak
Did you hear a loud squeak in the treetops?  It could be a southbound Rose-breasted Grosbeak stopping by for the day.
Rose-breasted Grosbeak
A Rose-breasted Grosbeak in a dead tree snag.
Swainson's Thrush
The Neotropical thrushes are beginning to move south now as well.  We found this newly arrived Swainson’s Thrush at Rocky Ridge County Park in York County during sunrise this morning.
Red-eyed Vireo
Not surprisingly, the Red-eyed Vireo is one of the most numerous of the migrants seen feeding in the deciduous canopy following a nocturnal flight event.  It’s not at all unusual to see dozens filing the trees around a ridgetop overlook or along a forest edge.  Be certain to check these congregations carefully, especially the groups of birds feeding in the lower branches of tall timber or in the tops of smaller trees.  This week we found…
Yellow-throated Vireo
…several hungry Yellow-throated Vireos arriving after nocturnal flights,…
Philadelphia Vireo
…and a Philadelphia Vireo (Vireo philadelphicus) at the hawkwatch at Rocky Ridge County Park in York County.
Red-breasted Nuthatch
Though not a Neotropical migrant, the easier-heard-than-seen Red-breasted Nuthatch is beginning to wander south into the lower Susquehanna region.  Most of these birds will eventually continue on to the pine forests of the southern United States for winter, but a few could remain to become seasonal visitors at feeding stations.
Ruby-throated Hummingbird
Ruby-throated Hummingbirds are on the move; their migration to the tropics is well underway and nearing its peak.  Ruby-throats are diurnal migrants that do a majority of their flying during the hours of daylight.  The notable exception: the nighttime portion of the long southbound flight some of the birds make to cross the Gulf of Mexico.
Red-headed Woodpecker
The Red-headed Woodpecker is another diurnal migrant.   This denizen of temperate climates is currently beginning to move to its wintering grounds, an area that extends from the latitudes of the lower Susquehanna south to the Gulf of Mexico and central Texas.
Juvenile Red-headed Woodpecker
A juvenile Red-headed Woodpecker during a brief pit stop.
Cedar Waxwings
The flights of roving bands of masked Cedar Waxwings continue.  Their numbers appear to be an improvement over those of 2023.
Broad-winged Hawk
At regional hawk-counting stations, observers are seeing more Broad-winged Hawks and other species beginning to move through.
"Kettling" Broad-winged Hawks
The frequency of Broad-winged Hawks passing the lookouts one at a time is giving way to the occurrence of larger and larger “kettling” groups that search out thermal updrafts to save energy while migrating.  By mid-September each of these “kettles” can include one hundred birds or more.  On the peak days, the daily Broad-winged Hawk totals can reach one thousand or more.
Broad-winged Hawk
A Broad-winged Hawk soaring to gain lift from a thermal updraft above a hawkwatch lookout.

The migration is by no means over; it has only just begun.  So plan to visit a local hawkwatch or other suitable ridgetop in coming weeks.  Arrive early (between 7 and 8 AM) to catch a glimpse of a nocturnal migrant fallout, then stay through the day to see the hundreds, maybe even thousands, of Broad-winged Hawks and other diurnal raptors that will pass by.  It’s an experience you won’t forget.

Broad-winged Hawk Gliding Away to the Southwest
A Broad-winged Hawk gliding away to the southwest.

Be certain to click the “Birds” tab at the top of this page for a photo guide to the species you’re likely to see passing south through the lower Susquehanna valley in coming months.  And don’t forget to click the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab to find a hawk-counting station near you.

More birds are on the way.  Here’s a look at this evening’s liftoff of nocturnal migrants detected by National Weather Service Radar in State College, Pennsylvania.  (NOAA/National Weather Service Doppler Radar image)

Southbound Flights: On Their Way Both Night and Day

It’s hard to believe, but for almost two months now, sandpipers, plovers, and terns have been filtering south through the Lower Susquehanna River Watershed on their way to the Atlantic coastline as they complete the first leg of their long autumn migration—a journey that will take some species all the way to the far reaches of the South American continent for winter.

Caspian Terns and Osprey
Migrating Caspian Terns and an Osprey take a break on a lower Susquehanna valley gravel bar.

As August draws to a close, these early birds are being joined by widespread nocturnal flights of Neotropical migrants—those species, primarily songbirds, on their way to wintering grounds which lie exclusively south of the continental United States.

To catch a glimpse of these night-flying avians, your best bet may be to position yourself on the crest of a ridge or along a linear break in the forest such as a utility right-of-way where waves of warblers, vireos, flycatchers, and other Neotropical passerines sometimes feed on invertebrates after making landfall at daybreak.  Pick a place where the trees are bathed in the warm light of the rising sun and be there by 7 A.M. E.D.T.  The activity can be tremendous, but it usually ends between 8 and 9.

Red-eyed Vireo
One of more than half a dozen Red-eyed Vireos seen during a daybreak fallout at Second Mountain Hawkwatch in Lebanon County earlier this week.
Blackburnian Warbler
During sunrise, a just-arrived Blackburnian Warbler checks the foliage of a ridgetop Red Maple for insects.
Least Flycatcher
A Least Flycatcher quietly searches the shrubby growth along the forest edge for a morning meal.
Black-and-white Warbler
A Black-and-white Warbler in the first hour of sunlight after a big nocturnal flight.
Scarlet Tanager
A Scarlet Tanager having a look around.  This individual and other migrating birds may be here for a few days before moving on.
Black-throated Green Warbler
A Black-throated Green Warbler in a treetop glowing with the light of sunrise.
Chestnut-sided Warbler
A hungry Chestnut-sided Warbler inspects limbs, leaves, and twigs looking for nourishment after an all-night flight.

Diurnal migrants, birds that make their movements during the daylight hours, are ramping up their flights now as well.  Broad-winged Hawks, Bald Eagles, and falcons are currently being tallied at hawk-counting stations throughout the northeast.  Many of those lookouts are seeing Ruby-throated Hummingbirds, swallows, and other daytime migrants too.

Broad-winged Hawk
While many diurnal migrants gather in flocks as a method of defense against predators, Broad-winged Hawks congregate as a reconnaissance measure.  Not waiting around for strong autumn winds to be deflected upwards by the region’s numerous ridges, these Neotropical birds migrate early enough in the season to rely upon thermal updrafts from sun-heated surfaces to provide lift, gain altitude, and save energy during their long trip.  By traveling in groups, there are collectively able to better locate and utilize rising air columns as they progress southwesterly along their route.  Broad-winged Hawks travel to Central and South America for winter.  Their numbers in the Lower Susquehanna River Watershed will peak during the third week of September.
American Kestrel
Many American Kestrels transit our area in August and early September, a time coinciding with flights of migratory dragonflies, insects upon which they and another falcon, the Merlin, frequently prey.
Chimney Swifts
Chimney Swifts are fast-flying diurnal migrants.  They are beginning to congregate into larger groups in preparation for their departure.  Some are already on the move.
Cedar Waxwing
Cedar Waxwings are currently being seen in roving flocks throughout the region.  Their migration is less of a point-to-point flight and more of a continuous wandering in search of berries and other wild foods.
American Goldfinch
Not everyone is yet ready to go.  American Goldfinches are still in the midst of their nesting cycle and won’t begin leaving until the young are on their own and colorful adult males like this one are beginning to molt into their drab winter plumage.

Autumn migration flights are an ever-changing process, with different species peaking at different times throughout the season.  In these months just after the nesting season, each of these species is more numerous than at any other time of the year.  And of course, the more often we as observers get out and have a look, the more of them we’ll see.

Be certain to click the “Birds” tab at the top of this page for a photo guide to the species you’re likely to see passing through the lower Susquehanna valley this fall.  Nearly four months of autumn hawk migration flights lie ahead, so don’t forget to click the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab to find a hawk-counting station near you, then stop by for a visit or two.  See you there!

A large nightfall liftoff of nocturnal migrating birds is shown here on this evening’s State College, Pennsylvania, Doppler Radar base velocity loop.  Returns indicating birds moving toward the radar site (the white dot in the center of the color mass) are shown in green, and those indicating birds moving away are indicated in red.  This is a big flight headed generally in a south-southwest direction.  (NOAA/National Weather Service Doppler Radar image)

Sightings on a Beautiful Spring Morning

Following a frosty night, sunny skies and a south breeze brought lots of action to the headquarters garden this morning.  Take a look…

Mason Bee at nest box
Mason Bees are quickly depositing their eggs and a mixture of pollen and nectar called a “pollen loaf” within holes we drilled into blocks of wood in our bee houses.  Each egg is laid in its own chamber within which the larva will hatch, feed on “pollen loaf”, and mature.  The individual cells, including the outermost one in the hole, are sealed with partitions made of mud.  It’s just like a mason using mortar.  Early next spring, the new generation of adults will emerge to begin the process once again.
Black Vulture
This morning’s south wind helped propel some northbound raptors.  This Black Vulture was the first we’ve seen from the headquarters garden since last fall.  While Turkey Vultures remain common and roost nearby, Black Vulture are noticeably less numerous since being impacted by avian flu one year ago.
Cooper's Hawk
This Cooper’s Hawk is one of pair nesting somewhere nearby.  It was quickly gaining altitude on a thermal…
Cooper's Hawks tangle.
…to intercept a transient Cooper’s Hawk (upper right) which it promptly escorted away to the north.
Broad-winged Hawk
Back from their winter holiday in the tropics, migrating Broad-winged Hawks are returning to breed in the forests of the north.  Watch for them either singly or in small groups as they “kettle” in thermal updrafts above south-facing slopes and sun-drenched paved surfaces.
American Robin at Bird Bath
Many birds including this American Robin have been frequenting our water features.  Remember to keep your fixture clean and change the water at least daily.  Watch the temperature too.  A late season freeze can leave you with a shattered bird bath.

This Week at Regional Hawk Watches

With nearly all of the Neotropical migrants including Broad-winged Hawks gone for the year, observers and counters at eastern hawk watches are busy tallying numbers of the more hardy species of diurnal raptors and other birds.  The majority of species now coming through will spend the winter months in temperate and sub-tropical areas of the southern United States and Mexico.

Here is a quick look at the raptors seen this week at two regional counting stations: Kiptopeke Hawk Watch near Cape Charles, Virginia, and Second Mountain Hawk Watch at Fort Indiantown Gap, Pennsylvania.

Kiptopeke Hawk Watch
The hawk-watching platform at Kiptopeke State Park is located along Chesapeake Bay near the southern tip of Delmarva Peninsula.  In autumn, thousands of raptors and other birds migrate through the Atlantic Coastal Plain Province.  Those that follow the shorelines south frequently concentrate in spectacular numbers before crossing the mouths of the bays they encounter.  This phenomenon makes both Cape May, New Jersey, on Delaware Bay and Kiptopeke, Virginia, on Chesapeake Bay exceptional places to experience fall flights of migrating birds.
Second Mounatin Hawk Watch
A Sharp-shinned Hawk is counted as it swoops by the owl decoy at Second Mountain Hawk Watch at Fort Indiantown Gap Military Reservation.  Migrating raptors save energy by riding updrafts of air created by winds blowing against the slopes of the mountainsides in the Ridge and Valley Province.
Sharp-shinned Hawk
A Sharp-shinned Hawk passes the lookout at Second Mountain Hawk Watch.  “Sharp-shins” are currently the most numerous migrants both on the coast and at inland counting stations.
Sharp-shinned Hawk
A Sharp-shinned Hawk nearly passes observers unnoticed as it skims the treetops.
Sharp-shinned Hawk at owl decoy.
A Sharp-shinned Hawk eyes up an owl decoy.  Under cover of darkness, nocturnal owls could rather easily prey upon young and small adult hawks and falcons, both on the nest or at roost.  Accordingly, many diurnal raptors instinctively harass owls to drive them from their presence.  An owl decoy at the lookout helps attract migrating birds for a closer look.
Cooper's Hawk
An adult Cooper’s Hawk flaps its way past a counting station.  Like the similar Sharp-shinned Hawk, the larger Cooper’s Hawk is a member of the genus Accipiter.  As a proportion of the annual fall Accipiter flight, the Cooper’s Hawk is more numerous at coastal hawk watches than at inland sites.
Osprey
The majority of Osprey migrate along the coast, but a few are still being seen at inland hawk watches.
Bald Eagle
Bald Eagles are commonly seen at both coastal and inland lookouts.  Their movements continue well into late fall.
Northern Harrier
A Northern Harrier illuminated by a setting sun.  Northern Harriers are often still flying when many other species have gone to roost for the day.
An adult male Northern Harrier flying in misty weather.
An adult male Northern Harrier, the “gray ghost”, flying in misty weather, at a time when few other birds were in the air. 
American Kestrel
The American Kestrel, like our other falcons, is seen in greatest concentrations at coastal counting stations.  It is our most numerous falcon.
Merlin
The Merlin provides only a brief observation opportunity as it passes the lookout.  These falcons are dark, speedy, and easily missed as they fly by.
Tree Swallow
While moving south, Merlins often accompany flights of migrating Tree Swallows, a potential food source.
Merlin with Dragonfly
A Merlin consumes a dragonfly.  Eating is no reason to stop moving.
Juvenile "Tundra Peregrine"
The “Tundra Peregrine” is an arctic-breeding Peregrine Falcon that travels a distance of over 6,000 miles to southern South America for winter.  It is strictly a migratory species in our region with numbers peaking during the first two weeks of October each year.  These strong fliers have little need for the updrafts from mountain ridges, inland birds often observed flying in a north to south direction.  The majority of “Tundra Peregrines” are observed following coastlines, with some migrating offshore to make landfall at points as far south as Florida and the Caribbean islands before continuing across water again to reach the northern shores of Central and South America.  This “Tundra Peregrine” is a juvenile bird on its first southbound trip.

During coming days, fewer and fewer of these birds will be counted at our local hawk watches.  Soon, the larger raptors—Red-tailed Hawks, Red-shouldered Hawks, and Golden Eagles—will be thrilling observers.  Cooler weather will bring several flights of these spectacular species.  Why not plan a visit to a lookout near you?  Click on the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab at the top of this page for site information and a photo guide to identification.  See you at the hawk watch!

Common Raven
It’s not all hawks at the hawk watch.  Even the coastal sites are now seeing fun birds like the playful Common Raven on a regular basis.
Eastern Meadowlarks in a Loblolly Pine.
Coastal locations are renowned places to see migrating songbirds in places outside of their typical habitat.  Here a flock of Eastern Meadowlarks has set down in the top of a Loblolly Pine (Pinus taeda) in downtown Cape Charles, Virginia, not far from Kiptopeke Hawk Watch.

A “Grasshopper Hawk” in the Susquehanna Valley

Tropical Storm Ophelia has put the brakes on a bustling southbound exodus of the season’s final waves of Neotropical migrants.  Winds from easterly directions have now beset the Mid-Atlantic States with gloomy skies, chilly temperatures, and periods of rain for an entire week.  These conditions, which are less than favorable for undertaking flights of any significant distance, have compelled many birds to remain in place—grounded to conserve energy.

Migrating Broad-winged Hawks on a Thermal Updraft
In the days prior to the arrival of Tropical Storm Ophelia, thousands of high-flying Broad-winged Hawks were being tallied as they passed hawk-counting stations throughout the region. As the last of this year’s migrants continue through, lack of clear skies, sunshine, and thermal updrafts has slowed the pace of their movements significantly.

Of the birds on layover, perhaps the most interesting find has been a western raptor that occurs only on rare occasions among the groups of Broad-winged Hawks seen at hawk watches each fall—a Swainson’s Hawk.  Discovered as Tropical Storm Ophelia approached on September 21st, this juvenile bird has found refuge in coal country on a small farm in a picturesque valley between converging ridges in southern Northumberland County, Pennsylvania.  Swainson’s Hawks are a gregarious species, often spending time outside of the nesting season in the company of others of their kind.  Like Broad-winged Hawks, they frequently assemble into large groups while migrating.

A juvenile Swainson's Hawk in Northumberland County, Pennsylvania.
A juvenile Swainson’s Hawk in Northumberland County, Pennsylvania.

Swainson's Hawk in Northumberland County, Pennsylvania.

Swainson’s Hawks nest in the grasslands, prairies, and deserts of western North America.  Their autumn migration to wintering grounds in Argentina covers a distance of up to 6,000 miles.  Among raptors, such mileage is outdone only by the Tundra Peregrine Falcon.

Juvenile Swainson's Hawk
The Swainson’s Hawk spends up to four months each year covering a 12,000-mile round-trip migration route.  The long primaries are an adaptation that give the wings additional lift, allowing them to use air currents including thermal updrafts to conserve energy while flying.

Juvenile Swainson's Hawk

Juvenile Swainson's Hawk
Swainson’s Hawks are renowned for spending time on the ground, intermittently running and hopping in pursuit of prey.

During the nesting cycle, Swainson’s Hawks consume primarily small vertebrates, mostly mice and other small rodents.  But during the remainder of the year, they feed almost exclusively on grasshoppers.  To provide enough energy to fuel their migrations, they must find and devour these insects by the hundreds.  Not surprisingly, the Swainson’s Hawk is sometimes known as the Grasshopper Hawk or Locust Hawk, particularly in the areas of South America where they are common.

Juvenile Swainson's Hawk eating a cricket.
The juvenile Swainson’s Hawk visiting Northumberland County has been feeding on grasshoppers, katydids, and is seen here eating a cricket.

So just how far will our wayward Swainson’s Hawk have to travel to get back on track?  Small numbers of Swainson’s Hawks pass the winter in southern Florida each year and still others are found in and near the scrublands of the Lower Rio Grande Valley in Texas and Mexico.  But the vast majority of these birds make the trip all the way to the southern half of South America and the farmlands and savannas of Argentina—where our winter is their summer.  The best bet for this bird would be to get hooked up with some of the season’s last Broad-winged Hawks when they start flying in coming days, then join them as they head toward Houston, Texas, to make the southward turn down the coast of the Gulf of Mexico into Central America and Amazonia.  Then again, it may need to find its own way to warmer climes.  Upon reaching at least the Gulf Coastal Plain, our visitor stands a much better chance of surviving the winter.

Juvenile Swainson's Hawk in Flight
As long as it can still find grasshoppers to eat, our wayward bird in Northumberland County still has time before it needs to make its way south.   As they pass through Texas, Mexico, Costa Rica, and Panama, Swainson’s Hawks are numerous among flocks of southbound Broad-winged Hawks.  But while hawk watches in these areas are presently recording maximum annual counts of the latter, peak numbers of the former won’t occur until the final two or three weeks of October.

Surf’s Up: The Waves Keep Rolling In

“Waves” of warblers and other Neotropical songbirds continue to roll along the ridgetops of southern Pennsylvania.  The majority of these migrants are headed to wintering habitat in the tropics after departing breeding grounds in the forests of southern Canada.  At Second Mountain Hawk Watch, today’s early morning flight kicked off at sunrise, then slowed considerably by 8:30 A.M. E.D.T.  Once again, in excess of 400 warblers were found moving through the trees and working their way southwest along the spine of the ridge.  Each of the 12 species seen yesterday were observed today as well.  In addition, there was a Northern Parula and a Canada Warbler.  Today’s flight was dominated by Bay-breasted, Blackburnian, Black-throated Green, and Tennessee Warblers.

A Blackburnian Warbler at sunrise on Second Mountain.
A Blackburnian Warbler at sunrise on Second Mountain.
A hungry Blackburnian Warbler feeding on insects.
A hungry Blackburnian Warbler feeding on insects.
Black-throated Green Warbler on Second Mountain.
Black-throated Green Warblers were a plentiful species among both yesterday’s and today’s waves of Neotropical migrants.
A juvenile Black-throated Green Warbler on Second Mountain
A juvenile Black-throated Green Warbler.
Tennessee Warbler on Second Mountain.
One of the scores of Tennessee Warblers seen on Second Mountain early this morning.
Cape May Warbler
Cape May Warblers were still common today, but not moving through in the numbers seen yesterday.
A male Black-throated Blue Warbler on Second Mountain.
A male Black-throated Blue Warbler.
Magnolia Warbler on Second Mountain.
Compared to yesterday’s flight, lesser numbers of Magnolia Warblers were seen today.
An adult male Wilson's Warbler on Second Mounatin.
An adult male Wilson’s Warbler was a good find among the hundreds of birds swarming the ridgetop.
Nashville Warbler
This Nashville Warbler spent much of the day in the tangles of Mile-a-minute Weed surrounding the lookout.

Other interesting Neotropical migrants joined the “waves” of warblers…

Red-eyed Vireo
Red-eyed Vireo numbers were higher than yesterday.
Warbling Vireo
This Warbling Vireo was found peering from the cover of the shady forest.
Rose-breasted Grosbeaks
A minimum of six Rose-breasted Grosbeaks were identified including the juvenile male seen here in first-fall plumage.  Other good sightings were Scarlet Tanagers, an adult male Baltimore Oriole, and a dozen or more Ruby-throated Hummingbirds.
Least Flycatcher on second Mountain.
Three Least Flycatchers were heard calling and seen chasing one another through a stand of dead timber on the south slope below the lookout.
Broad-winged Hawk
After the warbler flight settled, the task of counting migrating raptors commenced.  Five Broad-winged Hawks including this one were tallied as they glided away to the southwest for a winter vacation in the tropics of Central and South America.

Catch a Wave While You’re Sittin’ on Top of the World

During the recent couple of mornings, a tide of Neotropical migrants has been rolling along the crests of the Appalachian ridges and Piedmont highlands of southern Pennsylvania.  In the first hours of daylight, “waves” of warblers, vireos, flycatchers, tanagers, and other birds are being observed flitting among the sun-drenched foliage as they feed in trees along the edges of ridgetop clearings.  Big fallouts have been reported along Kittattiny Ridge/Blue Mountain at Hawk Mountain Sanctuary and at Waggoner’s Gap Hawk Watch.  Birds are also being seen in the Furnace Hills of the Piedmont.

Here are some of the 300 to 400 warblers (a very conservative estimate) seen in a “wave” found working its way southwest through the forest clearing at the Second Mountain Hawk Watch in Lebanon County this morning.  The feeding frenzy endured for two hours between 7 and 9 A.M. E.D.T.

Tennessee Warblers at Second Mountain Hawk Watch.
Tennessee Warblers (Leiothlypis peregrina) were very common among the migrants seen this morning on Second Mountain.
Tennessee Warbler at Second Mountain Hawk Watch.
An adult male Tennessee Warbler.
Nashville Warbler at Second Mountain Hawk Watch.
A Nashville Warbler.
Chestnut-sided Warbler at Second Mountain Hawk Watch.
A Chestnut-sided Warbler.
Cape May Warbler at Second Mountain Hawk Watch.
Cape May Warblers were another common species during the morning flight.
Magnolia Warbler at Second Mountain Hawk Watch.
Magnolia Warblers were frequently observed as well.
Black-and-white Warbler at Second Mountain Hawk Watch.
A Black-and-white Warbler exhibiting its nuthatch-like feeding behavior.
Blackburnian Warbler at Second Mountain Hawk Watch.
A Blackburnian Warbler.
Black-throated Green Warbler at Second Mountain Hawk Watch.
Black-throated Green Warblers were numerous.
Bay-breasted Warbler at Second Mountain Hawk Watch.
A Bay-breasted Warbler.
Wilson's Warbler at Second Mountain Hawk Watch.
This was the only Wilson’s Warbler discerned among the hundreds of warblers seen in a “wave” on Second Mountain this morning.

Not photographed but observed in the mix of species were several Black-throated Blue Warblers and American Redstarts.

In addition to the warblers, other Neotropical migrants were on the move including two Common Nighthawks, a Broad-winged Hawk, a Least Flycatcher (Empidonax minimus), and…

Scarlet Tanager at Second Mountain Hawk Watch.
At least half a dozen Scarlet Tanagers were in the treetops.
Ruby-throated Hummingbird at Second Mountain Hawk Watch.
And no less than 23 Ruby-throated Hummingbirds were counted cruising southbound past the lookout at Second Mountain Hawk Watch today.

Then, there was a taste of things to come…

Red-breasted Nuthatch at Second Mountain Hawk Watch.
One of 3 Red-breasted Nuthatches filling the air on the mountaintop with calls reminiscent of a toy tin horn.  Will this summer’s forest fires in Canada prompt a significant invasion of this and other birds including winter finches in coming months?  Time will tell.

Seeing a “wave” flight is a matter of being in the right place at the right time.  Visiting known locations for observing warbler fallouts such as hawk watches, ridgetop clearings, and peninsular shorelines can improve your chances of witnessing one of these memorable spectacles by overcoming the first variable.  To overcome the second, be sure to visit early and often.  See you on the lookout!

It’s Raptor and Warbler Migration Time

As we enter September, autumn bird migration is well underway.  Neotropical species including warblers, vireos, flycatchers, and nighthawks are already headed south.  Meanwhile, the raptor migration is ramping up and hawk watch sites throughout the Mid-Atlantic States are now staffed and counting birds.  In addition to the expected migrants, there have already been sightings of some unusual post-breeding wanderers.  Yesterday, a Wood Stork (Mycteria americana) was seen passing Hawk Mountain Sanctuary and a Swallow-tailed Kite (Elanoides forficatus) that spent much of August in Juniata County was seen from Waggoner’s Gap Hawk Watch while it was hunting in a Perry County field six miles to the north of the lookout!  Both of these rarities are vagrants from down Florida way.

A Peregrine Falcon speeds past the lookout at Second Mountain Hawk Watch.
A Peregrine Falcon speeds past the lookout at Second Mountain Hawk Watch yesterday.
Broad-winged Hawk
Later this month, numbers of high-flying Broad-winged Hawks moving past counting stations will reach their peak.  Most sites will experience one or more days with hundreds or perhaps thousands of these Neotropical migrants streaming by.
Black-and-white Warbler
This Black-and-white Warbler was found among a “wave” of migrating songbirds moving through some ridgetop trees.
Cape May Warbler
A juvenile Cape May Warbler peers from the cover of an Eastern Hemlock.

To plan a visit to a hawk watch near you, click on the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab at the top of this page to find a list and brief description of suggested sites throughout the Mid-Atlantic region.  “Hawkwatcher’s Helper” also includes an extensive photo guide for identifying the raptors you’re likely to see.

And to identify those confusing fall warblers and other migrants, click the “Birds” tab at the top of this page and check out the photo guide contained therein.  It includes nearly all of the species you’re likely to see in the lower Susquehanna valley.

Butterflies and More at Boyd Big Tree Preserve Conservation Area

If you’re feeling the need to see summertime butterflies and their numbers just don’t seem to be what they used to be in your garden, then plan an afternoon visit to the Boyd Big Tree Preserve along Fishing Creek Valley Road (PA 443) just east of U.S. 22/322 and the Susquehanna River north of Harrisburg.  The Pennsylvania Department of Conservation and Natural Resources manages the park’s 1,025 acres mostly as forested land with more than ten miles of trails.  While located predominately on the north slope of Blue Mountain, a portion of the preserve straddles the crest of the ridge to include the upper reaches of the southern exposure.

American Chestnut at Boyd Big Tree Preserve
A grove of American Chestnuts (Castanea dentata) planted at Boyd Big Tree Preserve is part of a propagation program working to restore blight-resistant trees to Pennsylvania and other areas of their former range which included the Appalachians and the upper Ohio River watershed.

Fortunately, one need not take a strenuous hike up Blue Mountain to observe butterflies.  Open space along the park’s quarter-mile-long entrance road is maintained as a rolling meadow of wildflowers and cool-season grasses that provide nectar for adult butterflies and host plants for their larvae.

Butterfly Meadow at Boyd Big Tree Preserve
A view looking north at the butterfly meadow and entrance road at Boyd Big Tree Preserve Conservation Area.  Second Mountain is in the background.
Walking a Meadow Path
Mowed paths follow the entrance road and a portion of the perimeter of the meadow allowing visitors a chance to wander among the waist-high growth to see butterflies, birds, and blooming plants at close range without trampling the vegetation or risking exposure to ticks.
A Silver-spotted Skipper feeding on nectar from Dogbane (Apocynum cannabinum) flowers.
A Silver-spotted Skipper feeding on nectar from the flowers of Indian Hemp (Apocynum cannabinum).  Like the milkweeds, Indian Hemp is a member of the dogbane family (Apocynaceae).
An Eastern Tiger Swallowtail feeding on Common Milkweed.
An Eastern Tiger Swallowtail feeding on Common Milkweed.
Great Spangled Fritillary on Common Milkweed.
A Great Spangled Fritillary (Speyeria cybele) on Common Milkweed.
A Black Swallowtail feeding on Common Milkweed nectar.
A Black Swallowtail (Papilio polyxenes) feeding on Common Milkweed nectar.
A Pipevine Swallowtail on Common Milkweed.
A Pipevine Swallowtail (Battus philenor) on Common Milkweed.
A Pipevine Swallowtail on Common Milkweed.
Another Pipevine Swallowtail on Common Milkweed.  Note the hook-shaped row of red-orange spots on the underside of the hindwing.
A Pipevine Swallowtail on visiting Butterfly Weed.
A Pipevine Swallowtail visiting the brilliant blooms of Butterfly Weed, a favorite of a wide variety of pollinators.
A Black Swallowtail on Butterfly Weed
A Black Swallowtail with damaged wings alights atop a Butterfly Weed flower cluster.  Note the pair of parallel rows of red-orange spot on the underside of the hindwing.
A Monarch on Butterfly Weed
A Monarch feeding on nectar from the flowers of Butterfly Weed.
A mating pair of Eastern Tailed Blues.
A mating pair of Eastern Tailed Blues on a Timothy (Phleum pratense) spike.
A female (left) and male Great Spangled Fritillary.
A male Great Spangled Fritillary (right) pursuing a female.
Common Green Darner
Butterflies aren’t the only colorful insects patrolling the meadows at Boyd Big Tree Preserve.  Dragonflies including Common Green Darners are busily pursuing prey, particularly small flying insects like mosquitos, gnats, and flies.
Juvenile Broad-winged Hawk
Dragonflies themselves can become prey and are much sought after by Broad-winged Hawks. This very vocal juvenile gave us several good looks as it ventured from the forest into the skies above the upper meadow during midday.  It wasn’t yet a good enough flier to snag a dragonfly, but it will have plenty of opportunities for practice during its upcoming fall migration which, for these Neotropical raptors, will get underway later this month.

Do yourself a favor and take a trip to the Boyd Big Tree Preserve Conservation Area.  Who knows?  It might actually inspire you to convert that lawn or other mowed space into much-needed butterfly/pollinator habitat.

While you’re out, you can identify your sightings using our photographic guide—Butterflies of the Lower Susquehanna River Watershed—by clicking the “Butterflies” tab at the top this page.  And while you’re at it, you can brush up on your hawk identification skills ahead of the upcoming migration by clicking the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab.  Therein you’ll find a listing and descriptions of hawk watch locations in and around the lower Susquehanna region.  Plan to visit one or more this autumn!

Photo of the Day

Female Red-winged Blackbirds in a cattail wetland.
This year’s unseasonably mild weather has hastened the northward migration of many birds.  Neotropical species including warblers and Broad-winged Hawks are already pushing through the lower Susquehanna region in numbers.  But it seems the spring movement may be a little bit protracted for female Red-winged Blackbirds, which are still rolling through by the hundreds despite the males being here, some of them defending nesting territories, since late February.  No sense of urgency?

Big Broad-winged Hawk Flights Are Underway

Flights of southbound Broad-winged Hawks have joined those of other Neotropical migrants to thrill observers with spectacular numbers.  In recent days, thousands have been seen and counted at many of the regions hawkwatching stations.  Now is the time to check it out!

A "kettle" of Broad-winged Hawks gaining altitude by soaring on a thermal updraft.
A “kettle” of Broad-winged Hawks gaining altitude by soaring on a thermal updraft.
Migrating Broad-winged Hawks
Broad-winged Hawks gliding away to the southwest after climbing in a column of rising warm air.
Broad-winged Hawk
A migrating Broad-winged Hawk enroute to the tropics for winter.

Other diurnal migrants are on the move as well…

Migratory Woodpeckers: Red-bellied Woodpecker and Northern Flicker
The Red-bellied Woodpecker (left) and the Northern Flicker (right) are migratory species of woodpeckers that begin heading south during the last half of September each year.
Migrating Blue Jay
Running a bit early, large numbers of Blue Jays having been moving through the area for several weeks now.
Flock of Cedar Waxwings
Flocks of Cedar Waxwings roam widely as they creep ever southward for winter.

Adding to the diversity of sightings, there are these diurnal raptors arriving in the area right now…

Juvenile Sharp-shinned Hawk
Numbers of migrating Sharp-shinned Hawks are building and will peak during the coming weeks.
Juvenile Cooper's Hawk
As will numbers of Cooper’s Hawks.
Merlin
The Merlin and other falcons peak in late September and early October.
Adult Bald Eagle
And Bald Eagles are moving throughout the fall season.

For more information and directions to places where you can observe migrating hawks and other birds, be certain to click the “Hawkwatcher’s Helper” tab at the top of this page.

Migration Update

Can it be that time already?  Most Neotropical birds have passed through the Lower Susquehanna River Watershed on their way south and the hardier species that will spend our winter in the more temperate climes of the eastern United States are beginning to arrive.

Here’s a gallery of sightings from recent days…

During the past two weeks, thousands of Broad-winged Hawks, including this adult bird, crossed the skies of the lower Susquehanna valley on their way to Central and South America for our winter.
A juvenile Broad-winged Hawk passes into the sunset during its first autumn migration.
Blackpoll Warblers are among the last of the Neotropical species to transit the region.  They’ll continue to be seen locally through at least early October.
Blue-headed Vireos are the October vireo during the fall, the other species having already continued toward tropical forests for a winter vacation.
The lower Susquehanna region lies just on the northern edge of the wintering range of the Blue-gray Gnatcatcher, a species found nesting locally among treetops in deciduous woods.  Look for their numbers to swell in coming days as birds from further north begin rolling through the region on their way south.
Sharp-shinned Hawks delight visitors at ridgetop hawk watches during breezy late-September and early-October days.  They allow closer observation than high-flying Broad-winged Hawks due to their habit of cruising just above the treetops while migrating.
A Sharp-shinned Hawk glides over a lookout.
Late September/early October is falcon time at area hawk-counting stations, the Peregrine Falcon often being the most anticipated species.
Pale “Tundra Peregrines”, a subspecies that nests in the arctic, are strictly migratory birds in the Mid-Atlantic States.  They are presently passing through on their way to South America.  Like Neotropical songbirds, their long flights provide them with the luxury of never experiencing a winter season.
This Carolina Saddlebags and other migratory dragonflies, which normally leave the area by mid-September, are still lingering in the lower Susquehanna region, much to the pleasure of the falcons that feed upon them.
An male American Kestrel in pursuit of dragonflies found swarming around the lookout at Second Mountain Hawk Watch in Lebanon County, Pennsylvania.
A male American Kestrel stooping on a dragonfly.
Osprey will be among the birds of prey passing hawk watch sites during the coming two weeks.  The first week of October often provides the best opportunity for seeing the maximum variety of raptors at a given site.  On a good day, a dozen species are possible.
Seeing cinnamon-colored juvenile Northern Harriers is symbolic of the October migration flights.
Bald Eagles always thrill the crowd.
In addition to raptors, resident Common Ravens are regularly sighted by observers at hawk watches and elsewhere during the fall season.
Hawk-counting stations sometimes log movements of Red-bellied Woodpeckers during late September and early October.  This species has extended its range into the Lower Susquehanna River Watershed only during the past one hundred years, making these seasonal migration movements a recent local phenomenon.
Blue Jays are currently on the move with breeding birds from the forests of Canada and the northern United States moving south.  Hundreds can be seen passing a given observation point during an ideal morning.
Blue Jays find a pile of peanuts to be an irresistible treat.  Provide the unsalted variety and watch the show!

Be sure to click on these tabs at the top of this page to find image guides to help you identify the dragonflies, birds, and raptors you see in the Lower Susquehanna River Watershed…

    • Damselflies and Dragonflies
    • Birds of Conewago Falls
    • Hawkwatcher’s Helper: Identifying Bald Eagles and other Raptors

See you next time!

Broad-winged Hawk Flights Underway

The smoke has cleared—at least for now—and Broad-winged Hawks are being seen migrating across lower Susquehanna valley skies.  Check out these daily counts from area hawk watches…

    • Rocky Ridge County Park Hawk Watch northeast of York, Pennsylvania: 475 Broad-winged Hawks on Saturday, September 18th—including 388 during the two hours between noon and 2 P.M.
    • Second Mountain Hawk Watch at Fort Indiantown Gap in Lebanon County, Pennsylvania: 300 Broad-winged Hawks on Wednesday, September 15th— one more than was tallied passing the site on the previous day.
    • Waggoner’s Gap Hawk Watch on Blue Mountain north of Carlisle, Pennsylvania: 1,211 Broad-winged Hawks on Tuesday, September 14th and 1,485 on Sunday, September 19th.
Broad-winged hawks in a “kettle” formation gaining altitude on a thermal updraft above Second Mountain Hawk Watch before continuing on their migratory journey.  “Kettling” can occur above any heat-generating surface on a sunny day, even a parking lot.
A migrating adult Broad-winged Hawk rising skyward.
A juvenile Broad-winged Hawk “feeding on the wing” consuming a dragonfly.

Additional Broad-winged Hawks are still working their way through the Mid-Atlantic States as they continue toward tropical wintering grounds.  And there’s more.  Numbers for a dozen other migratory hawk, eagle, and falcon species will peak between now and mid-November.  Days following passage of a cold front are generally best—so do get out there and have a look!

You can check the daily hawk count numbers and find detailed information for lookout sites all across North America at hawkcount.org

And don’t forget to click the “Hawkwatcher’s Helper” tab at the top of this page to see a gallery of photos that can help you to identify, and possibly determine the age of, the many species of raptors that occur in the Lower Susquehanna River Watershed.

A juvenile Merlin clutching a dragonfly takes a late-afternoon break from its migration flight.  Merlin numbers peak in early October.

Smoky Skies in the Lower Susquehanna Region

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.

During its passage through the Lower Susquehanna River Watershed, an adult Broad-winged Hawk sails over Second Mountain Hawk Watch in Lebanon County, Pennsylvania.
A hatch-year/juvenile Broad-winged Hawk gazes toward hawk watchers on the ground.

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.

The Carolina Saddlebags (Tramea carolina), this one photographed at Second Mountain Hawk Watch on September 8th, is the rarest of the lower Susquehanna region’s migratory dragonflies.  Autumn Broad-winged Hawk movements coincide with southbound flights of the Carolina Saddlebags and the more numerous migratory dragonfly species: Common Green Darner, Wandering Glider, Twelve-spotted Skimmer, and Black Saddlebags.  “Broad-wings” will often eat these and other dragonflies during migration and can sometimes be seen catching and feeding upon them while still soaring high overhead.

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.

Smoke from fires along the California coast and in central Utah can be seen streaming east this morning.  (NOAA/GOES image)
Smoke from western fires and humid air creates a band of haze in Ohio, Pennsylvania, New Jersey, and states to the south this morning.   (NOAA/GOES image)

 

A migrating Broad-winged Hawk in the glare of a hazy sky.  In addition to visibility problems, swarms of Spotted Lanternflies above the treetops make distant hawks difficult to discern for hawk watchers scanning the horizon with binoculars.

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.

Migrating Ospreys typically fly low enough and are large enough to be spotted even during the haziest of conditions.
Bald Eagles like this fourth-year bird can ascend to great altitude, but their size usually prevents them from sneaking past a lookout unnoticed.
Peregrines escape notice not due to hazy sky conditions, but because they pass by so quickly.  They’re being seen at local hawk watches now through October.

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…

Northern Parula at Chiques Rock County Park in Lancaster County.
Black-and-white Warbler at Rocky Ridge County Park in York County.
Cape May Warbler at Chiques Rock County Park in Lancaster County.
Bay-breasted Warbler at Rocky Ridge County Park in York County.

A Visit to Rocky Ridge

Early October is prime time for hawk watching, particularly if you want to have the chance to see the maximum variety of migratory species.  In coming days, a few Broad-winged Hawks and Ospreys will still be trickling through while numbers of Sharp-shinned Hawks, Cooper’s Hawks, Northern Harriers, and falcons swell to reach their seasonal peak.  Numbers of migrating Red-tailed and Red-shouldered Hawks are increasing during this time and late-season specialties including Golden Eagles can certainly make a surprise early visit.

If you enjoy the outdoors and live in the southernmost portion of the lower Susquehanna valley, Rocky Ridge County Park in the Hellam Hills just northwest of York, Pennsylvania, is a must see.  The park consists of oak forest and is owned and managed by the York County Parks Department.  It features an official hawk watch site staffed by volunteers and park naturalists.  Have a look.

The hawk watch lookout is reached by following the well-marked trail at the north side of the large gravel parking area in the utility right-of-way at the end of the park entrance road (Deininger Road).
The Rocky Ridge Hawk Watch lookout includes outcrops of bedrock, a viewing deck, and grassy areas suitable for lawn chairs.
The bedrock at the lookout is an unusual quartz-cemented conglomerate that forms the Hellam Member at the base of the Cambrian Chickies Formation.
Experienced hawk watchers conduct an official count of raptors and other birds during the autumn migration in September and October each year.  Visitors are welcome.  The view is spectacular.  Check out the concrete columns glowing in the sun to the north of the lookout.
It’s the cooling towers at the Three Mile Island Nuclear Station and the smoke stacks at the Brunner Island Steam Generating Station.  Conewago Falls is located between the two.
Interpretive signage on the hawk watch deck includes raptor identification charts.
A migrating Osprey glides by the lookout.
Throughout the month, migrating Sharp-shinned Hawks will be flying in a southwesterly direction along ridges in the region, particularly on breezy days.  They are the most numerous raptor at hawk watches in the lower Susquehanna valley during the first half of October.
A Peregrine Falcon quickly passes the Rocky Ridge lookout.  These strong fliers often ignore the benefits provided by thermals and updrafts along our ridges and instead take a direct north to south route during migration.
A juvenile Red-tailed Hawk soars by.
And a little while later, an adult Red-tailed Hawk follows.
Bald Eagles, including both migratory and resident birds, are seen regularly from the Rocky Ridge lookout.
Other diurnal (daytime) migrants are counted at Rocky Ridge and some of the other regional hawk watches.  Massive flights of Blue Jays have been working their way through the lower Susquehanna valley for more than a week now.  Local hawk watches are often logging hundreds in a single day.
The utility right-of-way within which the Rocky Ridge Hawk Watch is located can be a great place to see nocturnal (nighttime) migrants while they rest and feed during the day.  Right now, Eastern Towhees are common there.
An uncommon sight, a shy Lincoln’s Sparrow (Melospiza lincolnii) in the utility right-of-way near the hawk watch lookout.  This and other nocturnal migrants will take full advantage of a clear moonlit night to continue their southbound journey.

If you’re a nature photographer, you might be interested to know that there are still hundreds of active butterflies in Rocky Ridge’s utility right-of-way.  Here are a few.

A Gray Hairstreak.
An American Copper (Lycaena phlaeas),

To see the daily totals for the raptor count at Rocky Ridge Hawk Watch and other hawk watches in North America, and to learn more about each site, be certain to visit hawkcount.org

A Visit to Second Mountain

If it can fly, there’s a pretty good chance it was at Second Mountain today.

What follows is a photographic chronology of some of today’s sightings at Second Mountain Hawk Watch at Fort Indiantown Gap in Lebanon County, Pennsylvania.  We begin with some of the hundreds of migratory songbirds found at the base of the mountain along Cold Spring Road near Indiantown Run during the early morning, then we continue to the lookout for the balance of the day.

A Black-and-white Warbler (Mniotilta varia) searching the trunk of a tree for insects.
A Rose-breasted Grosbeak.
A Blackburnian Warbler high in the forest canopy.
A Black-throated Green Warbler bouncing from branch to branch as it feeds.
A Chestnut-sided Warbler lurks among the foliage.
A Magnolia Warbler.
One of a hundred or more Red-eyed Vireos found swarming the treetops, and occasionally the understory, while engaging in a wild feeding frenzy.
A male American Redstart.  Judging by that gray hood, it’s probably experiencing its second fall migration.
Eyes were skyward at the Second Mountain Hawk Watch lookout as Broad-winged Hawks began streaming through during the mid-morning.
During the morning flight, Broad-winged Hawks including this adult floated by the lookout riding updrafts created by the south wind striking the face of the mountain ridge.
As the overcast became more scattered and more sunlight reached the ground, Broad-winged Hawks began riding thermal currents to gain altitude before gliding off to the southwest in continuance of their long trip to the tropics.  At times, birds would disappear into the base of the clouds before ending their climb and sailing away.
Broad-winged Hawks rely principally upon amphibians and large insects like this bush katydid (Scudderia species) for sustenance.  With freezing temperatures just around the corner, “broad-wings” must make their way to warmer climes early or risk starvation.
A Bald Eagle always gets observers looking.
A juvenile Broad-winged Hawk.
A juvenile Cooper’s Hawk.
A Broad-winged Hawk has a look around.
One never quite knows what one may see when having a look around.
A Cape May Warbler (Setophaga tigrina) in the lookout hemlock.
A Black Saddlebags, one of several migratory dragonflies seen today.
An Osprey glides through in the afternoon glare.
A speedy Merlin thrilled observers with a close approach.
One must remember that Fort Indiantown Gap is an active military installation, so from time to time training and drilling exercises may interrupt bird observation activities at the Second Mountain Hawk Watch.
Today, speedy A-10 Warthog attack aircraft piloted by members of the Maryland Air National Guard based at Glenn Martin Field thrilled observers on the lookout with several close passes during their training runs.
And repeat.
Drill complete.

The total number of Broad-winged Hawks observed migrating past the Second Mountain lookout today was 619.  To see the daily raptor counts for Second Mountain and other hawk watches in North America, and to learn more about each site, be sure to visit hawkcount.org

Big Fallout

Okay, so it happened to be cloudy with drizzle at sunrise—not the best conditions for observing birds in the treetops.  But that inclement weather effectively grounded the overnight flight of migrating songbirds leading to a really big fallout in the lower Susquehanna valley this morning.

While straining one’s neck to gaze up into the forest canopy, hundreds of migrants including warblers, vireos, tanagers, thrushes, and flycatchers could be seen.  Identifying each was impossible.

Here are of few of this morning’s arrivals.  Manually setting the camera to a slower shutter speed compensated a little bit for the backlighting caused by cloudy conditions.

Pine Warbler (Setophaga pinus).
Bay-breasted Warbler.
Black-throated Green Warbler.
Nashville Warbler (Leiothlypis ruficapilla).
Northern Parula (Setophaga americana).

Peak numbers of Broad-winged Hawks will pass through the area during the coming two weeks.  They most often migrate in groups, with sizes ranging from several individuals to hundreds or even thousands of birds.  Despite this being a less than ideal day for riding thermals and gliding off towards the southwest to continue their journey to the tropics, some “broad-wings” ventured aloft and were on their way soon after the drizzle subsided during mid-morning.

A Broad-winged Hawk lifts off from the cover of the forest where it spent the night.
The same Broad-winged Hawk (bottom) and an adult Bald Eagle gain altitude on a thermal updraft before the former glides away toward the southwest.

Look What the Wind Blew In

It’s been more than a week since Tropical Storm Isaias moved swiftly up the Atlantic seaboard leaving wind and flood damage in its wake.  Here in the Lower Susquehanna River Watershed, the brevity of its presence minimized the effects.

Tropical Storm Isaias moves north-northeast across the Delmarva Peninsula.

You may have noticed some summertime visitors flying about during these hot humid days that followed Isaias’ passing.  They’re the dragonflies.

Our familiar friend the Wandering Glider is widespread throughout the valley right now—dropping eggs on shiny automobile hoods that look to them like a nice quiet puddle of water.

The Wandering Glider is a global traveler.  Here in the lower Susquehanna valley, it is currently abundant around still water and in large parking lots.

Each of the other common migratory species is here too.  Look for them patrolling the skies over large bodies of water and over adjacent fallow land and meadows where tiny flying insects abound.  Did these dragonflies arrive on the winds associated with the tropical storm, or did they move in with the waves of warm air that followed it?  Probably a little of both.

The Common Green Darner, a large dragonfly, can be the most abundant of the migratory species.  Watch for high-flying swarms in the coming weeks.
The Black Saddlebags is recognized in flight by the black base of each hindwing.  These patches give the appearance of a pair of saddlebags draped across the dragonfly’s thorax.
The Twelve-spotted Skimmer(Libellula pulchella) is a regular migrant.
The Prince Baskettail (Epitheca princeps) can occur among mixed groups of dragonflies.  Despite it rarely being mentioned as a migrant, its proclivity for non-stop day-long flight makes it a likely sighting among sizeable swarms.

Big swarms of dragonflies don’t go unnoticed by predators—particularly birds.  The southbound migration of kites, Broad-winged Hawks, American Kestrels, and Merlins often coincides with the swarming of migratory dragonflies in late summer.  Each of these raptors will grab and feed upon these insects while on the wing—so keep an eye on the sky.

This Peregrine Falcon found the congregations of hundreds of dragonflies worthy of a closer look…
…and an acrobatic fly-by to disrupt the swarms.  Fun, fun, fun, fun, fun.

Spotted Lanternfly in the Lower Susquehanna River Watershed

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 Broad-winged Hawks circle on a thermal updraft above Second Mountain Hawk Watch to gain altitude before gliding away to the southwest.

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.

This adult Spotted Lanternfly landed in a birch tree behind the observers at the Second Mountain Hawk Watch late this afternoon.  It was first recognized by its bright red wings as it glided from treetops on the north side of the lookout.

Blue Jay Way

The Neotropical birds that raised their young in Canada and in the northern United States have now logged many miles on their journey to warmer climates for the coming winter.  As their density decreases among the masses of migrating birds, a shift to species with a tolerance for the cooler winter weather of the temperate regions will be evident.

Though it is unusually warm for this late in September, the movement of diurnal migrants continues.  This morning at Conewago Falls, five Broad-winged Hawks (Buteo platypterus) lifted from the forested hills to the east, then crossed the river to continue a excursion to the southwest which will eventually lead them and thousands of others that passed through Pennsylvania this week to wintering habitat in South America.  Broad-winged Hawks often gather in large migrating groups which swarm in the rising air of thermal updrafts, then, after gaining substantial altitude, glide away to continue their trip.  These ever-growing assemblages from all over eastern North America funnel into coastal Texas where they make a turn to south around the Gulf of Mexico, then continue on toward the tropics.  In the coming weeks, a migration count at Corpus Christi in Texas could tally 100,000 or more Broad-winged Hawks in a single day as a large portion of the continental population passes by.  You can track their movement and that of other diurnal raptors as recorded at sites located all over North America by visiting hawkcount.org on the internet.  Check it out.  You’ll be glad you did.

Nearly all of the other migrants seen today have a much shorter flight ahead of them.  Red-bellied Woodpeckers (Melanerpes carolinus), Red-headed Woodpeckers (Melanerpes erythrocephalus), and Northern Flickers (Colaptes auratus) were on the move.  Migrating American Robins (Turdus migratorius) crossed the river early in the day, possibly leftovers from an overnight flight of this primarily nocturnal migrant.  The season’s first Great Black-backed Gulls (Larus marinus) arrived.  American Goldfinches are easily detected by their calls as they pass overhead.  Look carefully at the goldfinches visiting your feeder, the birds of summer are probably gone and are being replaced by migrants currently passing through.

By far, the most conspicuous migrant today was the Blue Jay.  Hundreds were seen as they filtered out of the hardwood forests of the diabase ridge to cautiously cross the river and continue to the southwest.  Groups of five to fifty birds would noisily congregate in trees along the river’s edge, then begin flying across the falls.  Many wary jays abandoned their small crossing parties and turned back.  Soon, they would try the trip again in a larger flock.

Sensing that they are being watched, Blue Jays are hesitant to fly across the narrow Susquehanna at Conewago Falls without first assembling into a flock.  The local constabulary often penalizes those who freelance and do not move in orderly groups.

A look at this morning’s count reveals few Neotropical migrants.  With the exception of the Broad-winged Hawks and warblers, the migratory species seen today will winter in a sub-tropical temperate climate, primarily in the southern United States, but often as far north as the lower Susquehanna River valley.  The individual birds observed today will mostly continue to a winter home a bit further south.  Those that will winter in the area of Conewago Falls will arrive in October and later.

The Great Blue Heron (Ardea herodius) can be found year-round at Conewago Falls, provided there is open water and adequate food.  Migrants from breeding colonies to the north will soon supplement the local population.
The Double-crested Cormorant (Phalacrocorax auritus) is a summer resident at Conewago Falls.  Migration of the local population and of those from further north will soon begin.  All will be gone by the time ice forms on the river.  Cormorants are often seen drying their feathers in sunlight following a series of feeding dives.

The long-distance migrating insect so beloved among butterfly enthusiasts shows signs of improving numbers.  Today, more than two dozen Monarchs were seen crossing the falls and slowly flapping and gliding their way to Mexico.

CLICK ON THE LOGO FOR TODAY’S MIGRATION COUNT TOTALS