Poorly Dressed for Dinner

By mid-summer, many birds exhibit less-than-stellar appearance.  Juveniles have just left the nest and although their plumage is completely fresh, it may look drab compared to the feathers the bird will sport upon reaching adulthood.  Their parents, having completed the stressful tasks of building nests and raising a new generation, now enter a state of molt to replace all or some of their adornment.  Now is a fortuitous time for these mature birds to exchange old feathers for new—food is plentiful and the need to keep warm and fly long distances is at a minimum.  Besides, they really don’t have to impress anyone with their beauty during summer vacation.

Following the break in the heat wave during recent days, activity at the headquarters feeders has increased significantly.  We took notice that many of our guests are looking a little rough around the edges.

Mourning Dove
Having started their nesting cycle in February, most Mourning Doves including this adult male are nearly done molting by mid-summer.  They are the exception.
Juvenile American Robin
This juvenile American Robin has acquired its first full set of flight feathers and will, in coming weeks, begin replacing the spotted plumage to more closely resemble an adult bird.
Male Northern Cardinal
This adult male Northern Cardinal in worn plumage is still tending to the needs of fledged young, but is nevertheless in the early stages of molt.
Juvenile Northern Cardinal
This juvenile Northern Cardinal will not only acquire brighter red feathers as an adult, but its bill will turn red as well.
Carolina Chickadee
This actively molting Carolina Chickadee shows pin feathers in the wings and is balding rather profusely.
Blue Jay
This Blue Jay has gone beyond having its feathers ruffled, but it’ll be good as new by the time autumn migration rolls around in September.
Juvenile European Starling
This drab brown bird is a juvenile European Starling.  While its first set of feathers looks complete, it has a big problem.  It lost its left eye and has trouble keeping up with a flock of its peers that have been roaming the area.  A predator will quickly notice this young bird’s vulnerabilities.
Downy Woodpecker
A juvenile Downy Woodpecker in a dull, streaky, almost dirty-looking, first plumage.  Unlike the adult male which has a red patch on the back of its head, the juvenile Downy Woodpecker has a mottled red crown.
Female Downy Woodpecker
An adult female Downy Woodpecker beginning to molt its heavily worn, year-old feathers.
Hairy Woodpecker
Mid-summer is prime time for discovering post-breeding wanders.  These are birds that spend the time between the end of nesting season and the fall migration roaming the countryside and sometimes visiting areas outside their more traditional habitats and/or native ranges.  For the past two days, this bird, a Hairy Woodpecker, has strayed from a mature woodland into urban environs to visit the garden at susquehannawildlife.net headquarters.  It’s our first record of one here.
American Goldfinches
Not yet a lot of molt among the American Goldfinches.  Why?  Well, they’re late-season breeders and are only now in the midst of their nesting cycle.  They begin shedding feathers and losing that brilliant color sometime in late August, just as the last of this year’s young are being fledged.

Think of all the opportunities mid-summer offers.  It’s a good time to get outdoors to have a look at all the young animals that are exploring their world for the first time.  Birds and other wildlife are at their greatest abundance of the year right now, so your chance to see new things is at its peak.  And the phenomenon of post-breeding wandering always raises the possibility of a surprise or two—maybe even a rarity.  Be cool and good luck!

Coming Soon, Very Soon: Brood X Periodical Cicadas

Yesterday, a hike through a peaceful ridgetop woods in the Furnace Hills of southern Lebanon County resulted in an interesting discovery.  It was extraordinarily quiet for a mid-April afternoon.  Bird life was sparse—just a pair of nesting White-breasted Nuthatches and a drumming Hairy Woodpecker.  A few deer scurried down the hillside.  There was little else to see or hear.  But if one were to have a look below the forest floor, they’d find out where the action is.

Not much action in the deer-browsed understory of this stand of hardwoods.
Upon discovery beneath a rock, this invertebrate quickly backed its way down the burrow, promptly seeking shelter in the underground section of the excavation.
A closeup of the same image reveals the red eyes of this Periodical Cicada (Magicicada species) nymph.  It has reached the end of seventeen years of slowly feeding upon the sap from a tree root to nourish its five instars (stages) of larval development.

2021 is an emergence year for Brood X, the “Great Eastern Brood”—the largest of the 15 surviving broods of Periodical Cicadas.  After seventeen years as subterranean larvae, the nymphs are presently positioned just below ground level, and they’re ready to see sunlight.  After tunneling upward from the deciduous tree roots from which they fed on small amounts of sap since 2004, they’re awaiting a steady ground temperature of about 64 degrees Fahrenheit before surfacing to climb a tree, shrub, or other object and undergo one last molt into an imago—a flying adult.

Here, approximately one dozen Periodical Cicada nymphs have tunneled into pre-emergence positions beneath a rock.  Seventeen-year Periodical Cicadas, sometimes mistakenly called “seventeen-year locusts”, are the longest-lived of our insects.
Note the wings and red eyes beneath the exoskeleton of this Periodical Cicada nymph. Within weeks it will join billions of others in a brief emergence to molt, dry, fly, mate, and die.
Adult (imago) Periodical Cicadas.  Brood X includes all three species of seventeen-year Periodical Cicadas: Magicicada septendecim, M. cassinii, and M. septendecula.  All Periodical Cicadas in the United States are found east of the Great Plains, the lack of trees there prohibiting the expansion of their range further west.  Seventeen-year life cycles account for twelve of the fifteen broods of Periodical Cicadas; the balance live for thirteen years.  The range of Brood X includes the lower Susquehanna basin and parts of Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, Ohio, Tennessee, Virginia, West Virginia, and the District of Columbia.  (United States Department of Agriculture/Agricultural Research Service image)
The flight of Periodical Cicadas peaks in late-May and June.  Shown here is the Eastern Scissor Grinder, an “Annual Cicada” that emerges later in the season, peaking yearly during July and August.

The woodlots of the Lower Susquehanna River Watershed won’t be quiet for long.  Loud choruses of male Periodical Cicadas will soon roar through forest and verdant suburbia.  They’re looking for love, and they’re gonna die trying to find it.  And dozens and dozens of animal species will take advantage of the swarms to feed themselves and their young.  Yep, the woods are gonna be a lively place real soon.

Did you say Periodical Cicadas?  We can hardly wait!

No Need to Hurry

It’s that time of year when one may expect to find migratory Neotropical songbirds feeding among the foliage of trees and shrubs in the forests, woodlots, and thickets of the lower Susquehanna valley.

During a late afternoon stroll through a headwaters forest east of Conewago Falls outside Mount Gretna, I was pleased to finally come upon a noisy gathering of about two dozen birds.  It had, previous to that, been a quiet two hours of walking, only the rumble of an approaching thunderstorm punctuated the silence.  Among this little flock were some chickadees, robins, Gray Catbirds, an Eastern Towhee (Pipilo erythrophthalmus), and a Hairy Woodpecker (Dryobates villosus).  Besides the catbirds, there were two other species of Neotropical migrants; both were warblers.  No less than six Black-throated Blue Warblers (Setophaga caerulescens) were  vying for positions in the trees from which they could investigate the stranger on the footpath below.  And among the understory shrubs there were at least as many Ovenbirds (Seiurus aurocapilla) satisfying a similar curiosity.

The Black-throated Blue Warbler nests to the north of the lower Susquehanna valley, which it transits as a common spring and fall migrant.  On their wintering grounds, they have a thing for warm weather and the better part of a P.B. & J. sandwich.
Throughout the Susquehanna watershed, the Ovenbird is a common ground-nesting species in deciduous forests with moderately vegetated understories.  The birds seen today may have been a family group that has not yet begun the journey south.

When they depart the Susquehanna valley, these two warbler species will be southbound for wintering ranges that include Florida, many of the Caribbean Islands, Central America, and, for the Ovenbirds, northern South America.  Their flights occur at night.  During the breeding season and while migrating, both feed primarily on insects and other arthropods .  On the wintering grounds, they will consume some fruit.  It is during their time in the tropics that the Black-throated Blue Warbler sometimes visits feeding stations that offer grape jelly, much to the delight of bird enthusiasts.

Black-throated Blue Warblers and Ovenbirds commonly winter on the Florida peninsula and in the Bahamas.  With the major tropical cyclone Hurricane Dorian presently ripping through the region, these birds are better off taking their time getting there.  There’s no need to hurry.  The longer they and the other Neotropical migrants hang around, the more we get to enjoy them anyway.  So get out there to see them before they go—and remember to look up.

Category 4 Hurricane Dorian at 9:06 EDT on September 2, 2019.  If you’re headed that direction, there’s no need to hurry.  Note the cloud-free skies over much of the mainland.  (NOAA National Environmental Satellite, Data, and Information Service image)
A massive bird migration is indicated on Doppler radar in the clear skies over the eastern United States tonight (blue and green over most of the mainland).  In this loop of composite radar images from the southeastern states, note the relative absence of a flight over the Florida peninsula where the outer precipitation bands of Hurricane Dorian can be seen.  Note too that there appears to be a heavy concentration of birds flying in a southwest direction to cross the Gulf of Mexico, thus continuing their journey to Central or South America while avoiding the deadly hurricane and a much smaller tropical disturbance off the shores of Texas and Tamaulipas, Mexico.  (NOAA/National Weather Service image)