Bathed in glowing sunshine, a very large fallout of migrating Neotropical songbirds enlivened the forest edge atop Second Mountain in northern Lebanon County, Pennsylvania, this morning. While last night’s flight was widespread beneath a dome of atmospheric high pressure covering the Mid-Atlantic States, this is a look at some of the 500 -1,000 migrants observed feeding on insects and other natural foods at just this single location.
As the composition of the nightly flights begins to transition to species that start their migration later in the season, numbers of birds like the Blackpoll Warbler (top) are beginning to rival those of the heretofore very common Black-throated Green Warbler (bottom).A Blackpoll Warbler.The Bay-breasted Warbler, another common species found among the fallout flock.The Tennessee Warbler was today’s most abundant migrant with at least 200 birds seen moving among the other species.A newly arrived Tennessee Warbler at sunrise.A Tennessee Warbler snatches breakfast.The Magnolia Warbler was another common find among today’s migrants.A Magnolia Warbler.A Nashville Warbler among tangles of Mile-a-minute Weed.A Nashville Warbler.Black-throated Blue Warbler.An adult male Black-throated Blue Warbler.An acrobatic Northern Parula.Blackburnian Warblers continue their southerly trek.An American Redstart.A Chestnut-sided Warbler feeding on Mile-a-minute Weed berries.A Cape May Warbler.A handsome adult male Cape May Warbler.A Swainson’s Thrush.Scarlet Tanagers continue to work their way south through the Lower Susquehanna River Watershed.A composite image of an uncommon find, a large-headed Olive-sided Flycatcher seen perched atop a dead tree snag.A brief encounter with a Philadelphia Vireo, another uncommon species.A Blue-headed Vireo, typically the last of its genus to move south in the fall, put in a welcome appearance among the hundreds of migrants.A favorite diurnal migrant, the Ruby-throated Hummingbird, was seen feeding on flowers that grew from the remains of garden waste dumped illegally along the mountain road last autumn.
Many of the observers at the Second Mountain Hawk Watch commented that this morning’s fallout was by far the best they had seen anywhere in the region during recent years. Others believed it to be the best they had ever seen. It was indeed less like a “wave” of migrants and more like a “tsunami”. Choosing a good viewing location and being there at the right time can improve your chances of seeing a spectacle like this. The good news is, it looks like another big flight is currently underway, so finding a forest edge on a ridgetop or along a utility right-of-way just might pay off for you early tomorrow morning.
Nocturnal migrating birds, a southwest-bound flight down the ridges of central Pennsylvania as indicated by Doppler radar between 10:30 and 11:30 PM EDT on September 11, 2024. (NOAA/National Weather Service image)
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…
A Black-throated Green Warbler.The Black-throated Green Warbler was perhaps the most frequently identified treetop warbler during the most recent four mornings.A Black-throated Green Warbler with a unique variation in the crown plumage.The Blackburnian Warbler was another plentiful species.Cape May Warblers have an affinity for conifers like this Eastern White Pine.But when traveling in mixed flocks with other migrants, Cape May Warblers can also be found feeding in the crown foliage of deciduous trees.This adult Tennessee Warbler appears to be adorned in a very worn set of plumage……and its traveling companion looks like it’s overdue for a new set of feathers as well.Like the Tennessee Warbler, the Nashville Warbler was common among mixed flocks.A Nashville Warbler atop a Black Cherry.This Chestnut-sided Warbler was one of several found among the more common species of migrants.A Chestnut-sided Warbler.We were lucky enough to spot this male Chestnut-sided Warbler sporting his namesake flank feathers.A Black-and-white Warbler uses its nuthatch-like feeding behavior to search the tree bark for edible invertebrates.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.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.Here we found a perky little House Wren.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.An Eastern Wood-Pewee fiercely defending its hunting perch.An Eastern Wood-Pewee.The numbers of migrating Least Flycatchers and other members of the genus Empidonax may be reaching their seasonal peak this week.Scarlet Tanagers are currently a common find following nocturnal flights.A Scarlet Tanager peers down from the top of a Red Maple.Did you hear a loud squeak in the treetops? It could be a southbound Rose-breasted Grosbeak stopping by for the day.A Rose-breasted Grosbeak in a dead tree snag.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.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……several hungry Yellow-throated Vireos arriving after nocturnal flights,……and a Philadelphia Vireo (Vireo philadelphicus) at the hawkwatch at Rocky Ridge County Park in York County.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 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.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.A juvenile Red-headed Woodpecker during a brief pit stop.The flights of roving bands of masked Cedar Waxwings continue. Their numbers appear to be an improvement over those of 2023.At regional hawk-counting stations, observers are seeing more Broad-winged Hawks and other species beginning to move through.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.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.
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)