It’s Bald Eagle Time, Wherever You Are

Now is a great time of year to see Bald Eagles in the Lower Susquehanna River Watershed.  For the population that breeds here in our region, it’s nesting season.  These birds are defending territories and some of them can get pretty aggressive towards the other eagles that happen to be wintering in the Susquehanna valley or will be migrating north through the area in coming weeks.  All that competition has these birds spending a lot of time in the air, so no matter where you happen to be, keeping an eye on the sky may provide you with an opportunity for a memorable glimpse of one or more eagles in action.  Skeptical?  Well, just an hour ago, we spotted these eagles high above the susquehannawildlife.net headquarters garden.

So do spend some time outdoors soon and while you’re there, don’t forget to look up.  You might turn some of your time into Bald Eagle time too!

The Fog of a January Thaw

As week-old snow and ice slowly disappears from the Lower Susquehanna River Watershed landscape, we ventured out to see what might be lurking in the dense clouds of fog that for more than two days now have accompanied a mid-winter warm spell.

York Haven Dam Powerhouse
After freezing to a slushy consistency earlier this week, the Susquehanna is already beginning to thaw.   Below the York Haven Dam at Conewago Falls, the water is open and ice-free.
Mallards and a pair of American Wigeon on a frozen lake.
On frozen man-made lakes and ponds, geese and ducks like these Mallards and American Wigeon are presently concentrated around small pockets of open water.
American Robin in a Callery pear
During the past ten days, American Robin numbers have exploded throughout the lower Susquehanna valley.  The majority of these birds may be a mix of both those coming south to escape the late onset of wintry conditions to our north and those inching north into our region as early spring migrants.
American Robin
The January thaw has melted the snow from lawns and fields to provide thousands of visiting robins with a chance to forage for earthworms.
Cooper's Hawk
A visit by this young Cooper’s Hawk to the susquehannnawildlife.net headquarters garden sent songbirds scrambling…
Eastern Gray Squirrel
…but did nothing to unnerve our resident Eastern Gray Squirrels,…
Eastern Gray Squirrel
…which promptly went into tail-waving mode to advertise their presence.
Red-tailed Hawk
But earlier in the week, when heavy snow cover in the rural areas surrounding our urbanized neighborhood made it difficult for rodent-eating raptors to find food, we received brief visits from both a Red-tailed Hawk…
Red-shouldered Hawk
…and this young Red-shouldered Hawk, an uncommon bird of prey most often found in wet woods and other lowlands.
Eastern Gray Squirrel
To escape notice during visits by these larger raptors, our squirrels remained motionless and commenced performance of their best bump-on-a-log impressions.
Red-shouldered Hawk in flight.
Unimpressed, each of our visiting buteos remained for just a few minutes before moving on in search of more favorable hunting grounds and prey.
Early Successional Growth
As snow melted and exposed bare ground in fields of early successional growth, we encountered…
White-crowned Sparrow
…a flock of White-crowned Sparrows, most in first-winter plumage…
American Tree Sparrow
…and at least a dozen American Tree Sparrows.  During the twentieth century, these handsome songbirds were regular winter visitors to the lower Susquehanna region.  During recent decades, they’ve become increasingly more difficult to find.  Currently, moderate numbers appear to be arriving to escape harsher weather to our north.
Adult Male Northern Harrier
What could be more appropriate on a foggy, gray evening than finding a “gray ghost” (adult male Northern Harrier) patrolling the fields in search of mice and voles.

If scenes of a January thaw begin to awaken your hopes and aspirations for all things spring, then you’ll appreciate this pair of closing photographs…

Pileated Woodpecker in Silver Maple
The maroon-red flower buds of Silver Maples are beginning to swell.  And woodpeckers including Pileated Woodpeckers are beginning to drum, a timber-pounding behavior they use to establish breeding territories in habitats with suitable sites for cavity nesting.
Skunk Cabbage
In wet soil surrounding spring seeps and streams, Skunk Cabbage is rising through the leaf litter to herald the coming of a new season.  Spring must surely be just around the corner.

Birds Along the River’s Edge

Just as bare ground along a plowed road attracts birds in an otherwise snow-covered landscape, a receding river or large stream can provide the same benefit to hungry avians looking for food following a winter storm.

Here is a small sample of some of the species seen during a brief stop along the Susquehanna earlier this week.

Song Sparrow
Along vegetated edges of the Susquehanna and its tributaries, the Song Sparrow is ubiquitous in its search for small seeds and other foods.  As the river recedes from the effects of this month’s rains, the shoreline is left bare of more recently deposited snow cover.  Song Sparrows and other birds are attracted to streamside corridors of frost-free ground to find sufficient consumables for supplying enough energy to survive the long cold nights of winter.
American Robin
Thousands of American Robins have been widespread throughout the lower Susquehanna valley during the past week.  Due to the mild weather during this late fall and early winter, some may still be in the process of working their way south.  Currently, many robins are concentrated along the river shoreline where receding water has exposed unfrozen soils to provide these birds with opportunities for finding earthworms (Lumbricidae) and other annelids.
Golden-crowned Kinglet
This Golden-crowned Kinglet was observed searching the trees and shrubs along the Susquehanna shoreline for tiny insects and spiders. Temperatures above the bare ground along the receding river can be a few degrees higher than in surrounding snow-covered areas, thus improving the chances of finding active prey among the trunks and limbs of the riparian forest.
Brown Creeper
Not far from the kinglet, a Brown Creeper is seen searching the bark of a Silver Maple (Acer saccharinum) for wintering insects, as well as their eggs and larvae.  Spiders in all their life stages are a favorite too.
American Pipits
American Pipits not only inhabit farm fields during the winter months, they are quite fond of bare ground along the Susquehanna.  Seen quite easily along a strip of pebbly shoreline exposed by receding water, these birds will often escape notice when spending time on mid-river gravel and sand bars during periods of low flow.
An American Pipit on a bitterly cold afternoon along the Susquehanna.
An American Pipit on a bitterly cold afternoon along the Susquehanna.

Migrating Ducks Find Emergency Refuge on the Susquehanna

As anticipated, lakes and ponds throughout the lower Susquehanna basin are beginning to freeze.  Fortunately for the waterfowl thereon, particularly diving ducks, the rain-swollen river is slowly receding and water clarity is improving to provide a suitable alternative to life on the man-made impoundments.

Ice-free Susquehanna at Harrisburg, Pennsylvania
The Susquehanna, ice-free and receding from near flood stage levels last week, can presently provide suitable habitat for diving ducks and other wintering waterfowl.
A Common Merganser on the Susquehanna in Dauphin County, Pennsylvania.
A feeding Common Merganser takes a breather between dives on the Susquehanna in Dauphin County, Pennsylvania.

The deep freeze is not only impacting ponds and lakes in the lower Susquehanna valley, but is evidently affecting the larger bodies of water to our north and northwest.  During Tuesday’s snow event, thousands of diving ducks arrived on the main stem of the river—apparently forced down by the inclement weather while en route to the Atlantic Coast from the Great Lakes and its connected waterways, which are currently beginning to freeze.

Ice-free Susquehanna
Tuesday’s snowfall not only blanketed the landscape with a coating of white,…
Bay Ducks on the Susquehanna
…it prompted thousands of migrating “bay ducks” including Canvasbacks, Redheads, scaup, and other diving species to seek open water and make a forced landing.
Scaup on the Susquehanna
Scaup were by far the most numerous of the birds in the grounded flight.  The majority appeared to be Lesser Scaup.
Scaup in flight.
Scaup in flight on the Susquehanna.
Scaup, Buffleheads, and Long-tailed Duck
A mixed raft of scaup and Buffleheads seen one day after a snowstorm-related fallout of late-season migrants.  A single Long-tailed Duck, a species formerly known as Oldsquaw, can be seen to the lower left.
Scaup, Bufflehead, and Long-tailed Duck
Scaup and a Bufflehead (center) fly past a Long-tailed Duck.  Because they winter primarily in coastal waters, both of the latter species are sometimes categorized as “sea ducks”.
Ruddy Ducks
A small flock of Ruddy Ducks.
Common Mergansers
While Common Mergansers on the Susquehanna are fish eaters (piscivores), other diving ducks observed during this fallout event are primarily benthic feeders, eating plant matter and invertebrate animals collected from the river bottom.
Common Goldeneyes
A small flock of Common Goldeneyes. They, like the Long-tailed Duck and Bufflehead, are sometimes known as a species of “sea duck”.
Scaup and Buffleheads
Another mixed raft of scaup and Buffleheads loafing on the Susquehanna.
Bald Eagle
Large numbers of waterfowl attract the attention of the river’s ever-vigilant Bald Eagles.
Adult Bald Eagle
An adult Bald Eagle patrolling the area of a fallout in search of dead, sick, or injured ducks.  In addition to the victims of naturally occurring ailments, eagles find birds and mammals wounded or killed by hunters to be particularly attractive sources of food.   They can, therefore, quite easily ingest pieces of shot.  Because eagles in the lower Susquehanna valley feed as frequently in upland habitats as they do in riverine environs, use of alternatives to toxic lead shot is prudent practice in all habitat types.
Fourth-year Bald Eagle
A Bald Eagle in the first month of its fourth calendar year.   Though not yet matured to breeding age, this bird is nevertheless smart enough to be on the lookout for vulnerable or deceased waterfowl during a post-storm fallout.
Seeing Some Waterfowl
A fallout of some migrating waterfowl seldom escapes notice by members of the gasoline and gunpowder gang…
Taking Aim at Some Waterfowl
…who find their very presence an irresistible temptation to arouse their adolescent urges…
Harrassing Some Waterfowl
…to get an adrenaline junkie’s fix.

With more snow on the way for tomorrow, you may be wondering if another fallout like this could be in the works.  The only way to find out is to get out there and have a look.  Good luck!  And be good!

Piscivorous Waterfowl Visiting Lakes and Ponds

Heavy rains and snow melt have turned the main stem of the Susquehanna and its larger tributaries into a muddy torrent.  For fish-eating (piscivorous) ducks, the poor visibility in fast-flowing turbid waters forces them to seek better places to dive for food.  With man-made lakes and ponds throughout most of the region still ice-free, waterfowl are taking to these sources of open water until the rivers and streams recede and clear.

Common Mergansers
The Common Merganser is a species of diving duck with a primary winter range that, along the Atlantic Coast, reaches its southern extreme in the lower Susquehanna and Potomac watersheds.  Recently, many have left the main stem of the muddy rivers to congregate on waters with better visibility at some of the area’s larger man-made lakes.
Common Mergansers Feeding
Common Mergansers dive to locate and capture prey, primarily small fish.  During this century, their numbers have declined along the southern edge of their winter range, possibly due to birds remaining to the north on open water, particularly on the Great Lakes.  In the lower Susquehanna valley, some of these cavity-nesting ducks can now be found year-round in areas where heavy timber again provides breeding sites in riparian forests.  After nesting, females lead their young to wander widely along our many miles of larger rivers and streams to feed.
Several Common Mergansers Intimidating a Male with a Freshly Caught Fish
The behavior of these mergansers demonstrates the stiff competition for food that can result when predators are forced away from ideal habitat and become compressed into less favorable space.  On the river, piscivores can feed on the widespread abundance of small fish including different species of minnows, shiners, darters, and more.  In man-made lakes stocked for recreational anglers with sunfish, bass, and other predators (many of them non-native), small forage species are usually nonexistent.  As a result, fish-eating birds can catch larger fish, but are successful far less often.  Seen here are several mergansers resorting to intimidation in an effort to steal a young bass away from the male bird that just surfaced with it.  While being charged by the aggressors, he must quickly swallow his oversize catch or risk losing it.

With a hard freeze on the way, the fight for life will get even more desperate in the coming weeks.  Lakes will ice over and the struggle for food will intensify.  Fortunately for mergansers and other piscivorous waterfowl, high water on the Susquehanna is expected to recede and clarify, allowing them to return to their traditional environs.  Those with the most suitable skills and adaptations to survive until spring will have a chance to breed and pass their vigor on to a new generation of these amazing birds.

Birds of Snow-covered Farmland

When the ground becomes snow covered, it’s hard to imagine anything lives in the vast wide-open expanses of cropland found in the Lower Susquehanna River Watershed’s fertile valleys.

Snow-covered Farm Field
A snow-covered field with no standing vegetation.  For nearly all wild birds, mammals, and other animals, modern agricultural practices offer no means of sustenance, particularly during the winter months.

Yet, there is one group of birds that can be found scrounging a living from what little exists after a season of high-intensity farming.  Meet the Horned Lark.

Horned Larks
Horned Larks occur year-round in the lower Susquehanna region.  Birds found wintering here are hardy individuals that breed in the arctic tundra, terrain reminiscent of our treeless farmlands.  Another population of larks seems to have adapted to no-till farming, nesting with some success in unplowed fields during the early part of the growing season.  The impact of herbicide application on survival of these broods could be a topic of research for an energetic student out there…hint, hint.
A Flock of Horned Larks
Nearly invisible on bare ground, Horned Larks are much more conspicuous after a fresh snowfall.  For protection from predators, they gather in flocks.  During the days of raw manure application, 300 to 500 larks could be found attracted to a freshly spread strip in a snow-covered field.  Modern liquid manure, which contains fewer undigested seeds and grains for larks, is not as attractive to these and other birds.
Horned Larks in Snow
During severe storms, we’ve seen Horned Larks remain active throughout the night.  We’ve even witnessed them taking shelter by burying themselves in the snow.
Horned Lark in Flight
To find food, Horned Larks are constantly on the move…
Horned Lark
…seeking out bare ground or the seed-bearing tops of plant stems that remain exposed above the snow.
Horned Larks Feeding at Roadside
Following storms, Horned Larks often gather along roadsides where snow removal has revealed “weed” seeds and other tiny morsels that, though they are almost imperceptible to us, are a meal for a Horned Lark.
A Horned Lark munching "weed" seeds.
A Horned Lark munching “weed” seeds.
Horned Larks and Lapland Longsrurs
Flocks of wintering Horned Larks will sometimes contain one or more of the several much less numerous species with a similar proclivity for tundra-like environs during the colder months.  We examined this gathering a little bit more closely…
Lapland Longspurs and Horned Larks
…and found these Lapland Longspurs (Calcarius lapponicus).  In winter, Lapland Longspurs (the two streaked birds: one to the far left and the other high-stepping the white line) can be hard to discern from the earth tones of farmland habitat.  Breeding males, however, are a brilliant white with a chestnut-colored nape and a black bib, mask, and cap.  On rare occasions, these males in spectacular alternate plumage can be found in the lower Susquehanna valley prior to their departure to nesting areas near the treeline in northern Canada and Alaska.
Horned larks and three Lapland Longspurs
A close-up image (through the windshield) of a roadside flock of Horned larks and three Lapland Longspurs (top, far right, and third from bottom).

If you decide to take a little post-storm trip to look for Horned Larks and Lapland Longspurs, be sure to drive carefully.  Do your searching on quiet rural roads with minimal traffic.  Stop and park only where line-of-sight and other conditions allow it to be done safely.  Use your flashers and check your mirrors often.  Think before you stop and park—don’t get stuck or make a muddy mess.  And most important of all, be aware that you’re on a roadway—get out of the way of traffic.

Eastern Meadowlarks
Flushed from roadside feeding areas by passing automobiles, these Eastern Meadowlarks were previously displaced from their grassland and pasture foraging areas by snow cover.

If you’re not going out to look for larks and longspurs, we do have a favor to ask of you.  Please remember to slow down while you’re driving.  Not only is this an accident-prone time of year for people in cars and trucks, it’s a dangerous time for birds and other wildlife too.  They’re at greatest peril of getting run over while concentrated along roadsides looking for food following snow storms.

American Pipit
The American Pipit is another barren-field specialist that can be found feeding at roadside following snowstorms, particularly when they coincide with the bird’s migration in late fall or early spring.  (Vintage 35 mm image)
Snow Bunting
The Snow Bunting (Plectrophenax nivalis), like the Lapland Longspur, occurs among flocks of Horned Larks in winter.  Other barren-ground birds you’ll see feeding along country roads following significant snowfalls include Savannah and Vesper Sparrows.
Killdeer
During mild winters, Killdeer may linger in farmlands where they are more easily heard than seen…until it snows.

Birds of the Sunny Grasslands

With the earth at perihelion (its closest approach to the sun) and with our home star just 27 degrees above the horizon at midday, bright low-angle light offered the perfect opportunity for doing some wildlife photography today.  We visited a couple of grasslands managed by the Pennsylvania Game Commission to see what we could find…

Grasslands and Hedgerows
On this State Game Lands parcel, prescribed fire is used to maintain a mix of grasslands and brushy early successional growth.  In nearby areas, both controlled fire and mechanical cutting are used to remove invasive species from hedgerows and the understory of woodlots.  Fire tolerant native species then have an opportunity to recolonize the forest and improve wildlife habitat.  This management method also reduces the fuel load in areas with the potential for uncontrolled wildfires.
The sun-dried fruits of a Common Persimmon tree found growing in a hedgerow.
The sun-dried fruits of a native Common Persimmon tree found growing in a hedgerow.
Savanna-like Grasslands
Just one year ago, mechanical removal of invasive trees and shrubs (including Multiflora Rose) on this State Game Land was followed by a prescribed fire to create this savanna-like grassland.
Song Sparrow
Hundreds of Song Sparrows were found in the grasses and thickets at both locations.
White-throated Sparrow
White-throated Sparrows were also abundant, but prefer the tangles and shrubs of the thickets.
Northern Mockingbird
Northern Mockingbirds were vigilantly guarding winter supplies of berries in the woodlots and hedgerows.
Swamp Sparrow
In grasses and tangles on wetter ground, about a dozen Swamp Sparrows were discovered.
White-crowned Sparrow
The adult White-crowned Sparrow is always a welcome find.
White-crowned Sparrow
And seeing plenty of juvenile White-crowned Sparrows provides some assurance that there will be a steady stream of handsome adult birds arriving to spend the winter during the years to come.
Dark-eyed Junco
Dark-eyed Juncos were encountered only in the vicinity of trees and large shrubs.
Savannah Sparrow
Several Savannah Sparrows were observed.  Though they’re mostly found in treeless country, this particular one happened to pose atop a clump of shrubs located within, you guessed it, the new savanna-like grasslands.
Winter Wren
A tiny bird, even when compared to a sparrow, the Winter Wren often provides the observer with just a brief glimpse before darting away into the cover of a thicket.
Standing Clump of Timber
Within grasslands, scattered stands of live and dead timber can provide valuable habitat for many species of animals.
A "snag" with an excavated nest cavity.
Woodpeckers and other cavity-nesting birds rely upon an abundance of “snags” (standing dead trees) for breeding sites.
Red-bellied Woodpecker
This Red-bellied Woodpecker and about a dozen others were found in trees left standing in the project areas.
Yellow-bellied Sapsucker
A Yellow-bellied Sapsucker soaks up some sun.
Pileated Woodpecker
This very cooperative Pileated Woodpecker seemed to be preoccupied by insect activity on the sun-drenched bark of the trees.  This denizen of mature forests will oft times wander into open country where larger lumber is left intact.

Pileated Woodpecker

Northern Harrier
Just as things were really getting fun, some late afternoon clouds arrived to dim the already fading daylight.  Just then, this Northern Harrier made a couple of low passes in search of mice and voles hidden in the grasses.
Northern Harrier
It was a fitting end to a very short, but marvelously sunny, early winter day.

Want Healthy Floodplains and Streams? Want Clean Water? Then Make Room for the Beaver

I’m worried about the beaver.  Here’s why.

Imagine a network of brooks and rivulets meandering through a mosaic of shrubby, sometimes boggy, marshland, purifying water and absorbing high volumes of flow during storm events.  This was a typical low-gradient stream in the valleys of the Lower Susquehanna River Watershed in the days prior to the arrival of the trans-Atlantic human migrant.  Then, a frenzy of trapping, tree chopping, mill building, and stream channelization accompanied the east to west waves of settlement across the region.  The first casualty: the indispensable lowlands manager, the North American Beaver (Castor canadensis).

Beaver Traps
Nineteenth-century beaver traps on display in the collection of the State Museum of Pennsylvania in Harrisburg.  Soon after their arrival, Trans-Atlantic migrants (Europeans) established trade ties to the trans-Beringia migrants (“Indians”) already living in the lower Susquehanna valley and recruited them to cull the then-abundant North American Beavers.  By the early 1700s, beaver populations (as well as numbers of other “game” animals) were seriously depleted, prompting the Conoy, the last of the trans-Beringia migrants to reside on the lower Susquehanna, to disperse.  The traps pictured here are samples of the types which were subsequently used by the European settlers to eventually extirpate the North American Beaver from the Lower Susquehanna River Watershed during the 1800s.

Without the widespread presence of beavers, stream ecology quickly collapsed.  Pristine waterways were all at once gone, as were many of their floral and faunal inhabitants.  It was a streams-to-sewers saga completed in just one generation.  So, if we really want to restore our creeks and rivers, maybe we need to give the North American Beaver some space and respect.  After all, we as a species have yet to build an environmentally friendly dam and have yet to fully restore a wetland to its natural state.  The beaver is nature’s irreplaceable silt deposition engineer and could be called the 007 of wetland construction—doomed upon discovery, it must do its work without being noticed, but nobody does it better.

North American Beaver diorama on display in the State Museum of Pennsylvania in Harrisburg.
North American Beaver diorama on display in the State Museum of Pennsylvania in Harrisburg.  Beavers were reintroduced to the Susquehanna watershed during the second half of the twentieth century.
A beaver dam on a small stream in the Lower Susquehanna River Watershed.
A beaver dam and pond on a small stream in the Lower Susquehanna River Watershed.
Floodplain Wetlands Managed by North American Beavers
Beaver dams not only create ponds, they also maintain shallow water levels in adjacent areas of the floodplain creating highly-functional wetlands that grow the native plants used by the beaver for food.  These ecosystems absorb nutrients and sediments.  Prior to the arrival of humans, they created some of the only openings in the vast forests and maintained essential habitat for hundreds of species of plants as well as animals including fish, amphibians, reptiles, and birds.  Without the beaver, many of these species could not, and in their absence did not, exist here.
The beaver lodge provides shelter from the elements and predators for a family of North American Beavers.
Their newly constructed lodge provides shelter from the elements and from predators for a family of North American Beavers.
Sandhill Cranes Visit a Beaver-managed Floodplain in the lower Susquehanna valley
Floodplains managed by North American Beavers can provide opportunities for the recovery of the uncommon, rare, and extirpated species that once inhabited the network of streamside wetlands that stretched for hundreds of miles along the waterways of the Lower Susquehanna River Watershed.
Great Blue Heron
A wintering Great Blue Heron is attracted to a beaver pond by the abundance of fish in the rivulets that meander through its attached wetlands.
Sora Rail in Beaver Pond
Beaver Ponds and their attached wetlands provide nesting habitat for uncommon birds like this Sora rail.
Wood Duck feeding on Lesser Duckweed in Beaver Pond
Lesser Duckweed grows in abundance in beaver ponds and Wood Ducks are particularly fond of it during their nesting cycle.
Sandhill Cranes feeding among Woolgrass in a Beaver Pond
Beaver dams maintain areas of wet soil along the margins of the pond where plants like Woolgrass sequester nutrients and contain runoff while providing habitat for animals ranging in size from tiny insects to these rare visitors, a pair of Sandhill Cranes (Antigone canadensis).
Sandhill Cranes feeding among Woolgrass in a floodplain maintained by North American Beavers.
Sandhill Cranes feeding among Woolgrass in a floodplain maintained by North American Beavers.

Few landowners are receptive to the arrival of North American Beavers as guests or neighbors.  This is indeed unfortunate.  Upon discovery, beavers, like wolves, coyotes, sharks, spiders, snakes, and so many other animals, evoke an irrational negative response from the majority of people.  This too is quite unfortunate, and foolish.

North American Beavers spend their lives and construct their dams, ponds, and lodges exclusively within floodplains—lands that are going to flood.  Their existence should create no conflict with the day to day business of human beings.  But humans can’t resist encroachment into beaver territory.  Because they lack any basic understanding of floodplain function, people look at these indispensable lowlands as something that must be eliminated in the name of progress.  They’ll fill them with soil, stone, rock, asphalt, concrete, and all kinds of debris.  You name it, they’ll dump it.  It’s an ill-fated effort to eliminate these vital areas and the high waters that occasionally inundate them.  Having the audacity to believe that the threat of flooding has been mitigated, buildings and poorly engineered roads and bridges are constructed in these “reclaimed lands”.  Much of the Lower Susquehanna River Watershed has now been subjected to over three hundred years-worth of these “improvements” within spaces that are and will remain—floodplains.  Face it folks, they’re going to flood, no matter what we do to try to stop it.  And as a matter of fact, the more junk we put into them, the more we displace flood waters into areas that otherwise would not have been impacted!  It’s absolute madness.

By now we should know that floodplains are going to flood.  And by now we should know that the impacts of flooding are costly where poor municipal planning and negligent civil engineering have been the norm for decades and decades.  So aren’t we tired of hearing the endless squawking that goes on every time we get more than an inch of rain?  Imagine the difference it would make if we backed out and turned over just one quarter or, better yet, one half of the mileage along streams in the Lower Susquehanna River Watershed to North American Beavers.  No more mowing, plowing, grazing, dumping, paving, spraying, or building—just leave it to the beavers.  Think of the improvements they would make to floodplain function, water quality, and much-needed wildlife habitat.  Could you do it?  Could you overcome the typical emotional response to beavers arriving on your property and instead of issuing a death warrant, welcome them as the talented engineers they are?  I’ll bet you could.

Photo of the Day

Wildflower Meadow Project underway at East Donegal Riverfront Park
Here’s something to look forward to in the new year.  The good citizens of East Donegal Township in Lancaster County have partnered with Alliance for the Chesapeake Bay to establish an extensive wildflower meadow on what had been a mowed field of turf grass at Riverside Park in the Susquehanna floodplain near Marietta.  As the photo shows, the lawn plants have been eliminated in preparation for seeding with a diverse assortment of native grasses and wildflowers to provide habitat for birds and pollinators including butterflies, bees, and other insects.  Once established, the meadow’s extensive vegetative growth will help reduce stormwater runoff by better infiltrating rainfall to recharge the aquifer.  During flood events, the plantings will provide soil stabilization and increase the ability of the acreage to uptake nutrients, thus reducing the negative impact of major storms on the quality of water in the river and in Chesapeake Bay.  Check the project’s progress by stopping by from time to time in 2024!

Photo of the Day

Green Frog on Christmas
It’s been a green Christmas at susquehannawildlife.net headquarters.  Among thick growth of Lesser Duckweed and other aquatic plants in the garden ponds, the Green Frogs and their tadpoles remain active.  The water’s open…still no ice here.

Western Flycatcher on the Susquehanna

What was the attraction that prompted dozens of birders to hike more than a mile to a secluded field edge along the Northwest Lancaster County River Trail on this last full day of autumn?  It must be something good.

Birders photographing a rarity in the vicinity of the Shock's Mill Railroad Bridge along the Susquehanna in Lancaster County
Birders photographing a rarity in the vicinity of the Shock’s Mill Railroad Bridge along the Susquehanna in Conoy Township, Lancaster County, earlier today.

Indeed it was.  A Western Flycatcher (Empidonax difficilis), first discovered late last week, has weathered the coastal storm that in recent days pummeled the Lower Susquehanna River Watershed with several inches of rain and blustery winds.  Western Flycatchers nest in the Rocky Mountain and Pacific Coast regions of North America.  They spend their winters in Mexico.  There are several records of these tiny passerines in our area during December.  The first, a bird found in an area known as Tanglewood during the Southern Lancaster County Christmas Bird Count (CBC) on December 16, 1990, was well documented—photographs were taken and its call was tape recorded.  It constituted the first record of a member of the Western Flycatcher’s “Pacific-slope” subspecies group ever seen east of the Mississippi River.  It was reported through December 26, 1990.  The Tanglewood flycatcher and a bird sighted years later on a subsequent “Solanco CBC” were both found inhabiting wooded thickets in the shelter of a ravine created by one of the Susquehanna’s small tributaries.

Western Flycatcher along Northwest Lancaster County River Trail
Early this morning, a vagrant Western Flycatcher finds a sunny spot adjacent to the Northwest Lancaster County River Trail to search the vines, shrubs, and tree limbs for spiders and small insects.
Western Flycatcher along Northwest Lancaster County River Trail
The diminutive Western Flycatcher on the lookout for flying insects from an elevated perch in the treetops.
Western Flycatcher along Northwest Lancaster County River Trail
Like other Western Flycatchers which have been found during the month of December in Lancaster County, this individual has some topographic protection from cold northwest winds.  It spends its time in a thicket along the edge of woodlands on the leeward side of the railroad grade that rises as the approach to the nearby Shock’s Mill Bridge.

How long will this wandering rarity remain along the river trail?  For added sustenance, sunny days throughout the coming winter offer ever-increasing chances of stonefly hatches on the adjacent river, particularly in the vicinity of the stone bridge piers.  But ultimately, the severity of the weather and the bird’s response to it will determine its destiny.

Photo of the Day

Rising Susquehanna River at Northwest Lancaster County River Trail underpass at Shock's Mill Railroad Bridge, December 18, 2023.
Torrential rains throughout the Susquehanna watershed last night have the river’s main stem on the rise today.  By late this afternoon, the Northwest Lancaster County River Trail’s underpass beneath the Shock’s Mill Bridge was just 18 inches from inundation.  An additional seven feet or more of flood water is expected at this location by the time the river reaches its crest on Wednesday.

Photo of the Day

Bald Eagle
The last of the year’s migrating Bald Eagles are streaming down the ridges of the mid-Atlantic region and many of them will be stopping for at least a part of the winter season along the lower Susquehanna River.  If you want to see them, now is the best time.  Taking a walk along a riverside recreation trail is a relaxing way to spend some time checking them out.  To see the greatest concentrations of these majestic birds, plan a visit to one of the lower river’s hydroelectric dams.  Conowingo Dam, located where U.S. Route 1 crosses the river at Rising Sun, Maryland, is currently hosting dozens of visiting eagles.  If you’ve never been there, we can assure you that it’s certainly worth the trip.

Rare Barthelemyi Variant of the Golden Eagle Seen Migrating Along Second Mountain

As the autumn raptor migration draws to a close in the Lower Susquehanna Valley Watershed, observers at the Second Mountain Hawk Watch in Lebanon County, Pennsylvania, were today treated to a flight of both Bald and Golden Eagles.  Gliding on updrafts created by a brisk northwest breeze striking the slope of the ridge, seven of the former and three of the latter species were seen threading their way through numerous bands of snow as they made their way southwest toward favorable wintering grounds.

The best and final bird of the day, and possibly one of the highlights of the season at this counting station, was a “Barthelemyi Golden Eagle”, a rare Golden Eagle variant with conspicuous shoulder epaulets created by white scapular feathers.

"Barthelemyi Golden Eagle" passing the Second Mountain Hawk Watch in Lebanon County, Pennsylvania.
The grand finale, a “Barthelemyi Golden Eagle”, passed the Second Mountain Hawk Watch during a break in the afternoon’s snow showers.  Note the bright white scapulars at the base of the leading edge of the wing.
"Barthelemyi Golden Eagle" passing the Second Mountain Hawk Watch in Lebanon County, Pennsylvania.
Barthelemyi variants are known from populations of Golden Eagles in the Alps of southern Europe and from both eastern and western populations of birds in North America.  Spofford (1961) documented a pair of Golden Eagles with the Barthelemyi traits nesting in eastern North America.  In two successive seasons they produced young that developed the same plumage characteristics, suggesting the variation may be passed to offspring by one or more genetic alleles.

Today’s rarity is the second record of a “Barthelemyi Golden Eagle” at Second Mountain Hawk Watch—the first occurring on October 21, 2017.

SOURCES

Spofford, W. R.  1961.  “White Epaulettes in Some Appalachian Golden Eagles”.  Prothonotary.  27: 99.

Photos of a Visiting Cooper’s Hawk

While trimming the trees and shrubs in the susquehannawildlife.net garden, it didn’t seem particularly unusual to hear the resident Carolina Chickadees and Carolina Wrens scolding our every move.  But after a while, their persistence did seem a bit out of the ordinary, so we took a little break to have a look around…

Carolina Wren
A scolding Carolina Wren…
Carolina Wren
…keeping an eye on something in the tree overhead.
Juvenile Cooper's Hawk
There, just ten to twelve feet away, was this juvenile Cooper’s Hawk, perched quietly and having a look around.
Juvenile Cooper's Hawk
Hatch-year Cooper’s Hawks have yellow eyes that darken to red as the bird matures.  The blood stains reveal that this bird, despite its young age, is a successful hunter.
Juvenile Cooper's Hawk
This individual seems to be particularly well nourished, showing early growth of a gray-and-black adult tail feather.
Juvenile Cooper's Hawk
Despite their continuous pestering, this Cooper’s Hawk showed little interest in the small wrens, juncos, and chickadees that harassed it.  Larger birds, particularly non-native House Sparrows, are its quarry.  Moments after this photo was taken, the pursuit was underway.  To conserve energy and protect themselves from injury, predators target the vulnerable.  The unwary, the injured, the diseased, and the weak among its prey species are the most likely to be seized.  And thus, these raptors, while in the near term providing for their own sustenance and safety, assure the long-term existence of their species by helping to maintain a healthy population of their prey species.

Here at susquehannawildlife.net headquarters, we are visited by Cooper’s Hawks for several days during the late fall and winter each year.  The small birds that visit our feeders have plenty of trees, shrubs, vines, and other natural cover in which to hide from raptors and other native predators.  We don’t create unnatural concentrations of birds by dumping food all over the place.  We try to keep our small birds healthy by sparingly offering fresh seed and other provisions in clean receptacles to provide a supplement to the seeds, fruits, insects, and other foods that occur naturally in the garden.  With only a few vulnerable small birds around, the Cooper’s Hawks visit just long enough to cull out our weakest individuals before moving elsewhere.  While they’re in our garden, they too are our welcomed guests.

Time to Eat

A glimpse of the rowdy guests crowding the Thanksgiving Day dinner table at susquehannawildlife.net headquarters…

White-breasted Nuthatch
A male White-breasted Nuthatch visits a peanut feeder…
White-breasted Nuthatch
…soon to be joined by a female White-breasted Nuthatch.
Downy Woodpecker
A male Downy Woodpecker gets a bill full of suet.
Carolina Wren
A Carolina Wren nibbles at a peanut.
Eastern Gray Squirrel
An Eastern Gray Squirrel stuffs itself on peanuts dropped by the birds.
Northern Mockingbird
A territorial Northern Mockingbird stands guard over its supply of Common Winterberry fruit.
Eastern Bluebird
To avoid the mockingbird’s aggression, the Eastern Bluebirds opted out of fresh fruit in favor of raisins offered at the feeders.
American Robin
This persistent American Robin has made an art of repeatedly sneaking in to quickly devour a few berries before being chased away by the vigilant mockingbird.
Dark-eyed Junco
After everyone has had their fill, Dark-eyed Juncos clean up the leftovers.

Sparrows in the Thicket

As the annual autumn songbird migration begins to reach its end, native sparrows can be found concentrating in fallow fields, early successional thickets, and brushy margins along forest edges throughout the Lower Susquehanna River Watershed.

Brushy Thicket
A streamside thicket composed of seed-producing grasses and wildflowers as well as fruit-bearing shrubs and vines can be ideal habitat for migrating and wintering native sparrows.

Visit native sparrow habitat during mid-to-late November and you have a good chance of seeing these species and more…

Song Sparrow
The Song Sparrow can be found in woody brush and grassy margins from the shores of the Susquehanna all the way up to the ridgetops of the Appalachians.
Dark-eyed junco
During the colder months of the year, the Dark-eyed Junco is a familiar visitor to bird-feeding stations.  Where suitable natural cover is present, they regularly venture into suburban and urban settings.
White-throated Sparrow
The White-throated Sparrow is commonly found in the company of juncos, but is generally less adventurous, being more likely in weedy fields near young woodlands than in suburban gardens.
Eastern Towhee
The Eastern Towhee is a large native sparrow most often found in early successional growth near woodlands.  Look for them in utility right-of-ways.
Fox Sparrow
The elusive Fox Sparrow is a regular late-fall migrant.  Few stay for the winter, but northbound birds can be seen as early as mid-February each year.

If you’re lucky enough to live where non-native House Sparrows won’t overrun your bird feeders, you can offer white millet as a supplement to the wild foods these beautiful sparrows might find in your garden sanctuary.  Give it a try!

Getting a Head Start on Spring

Recently, we found these Chestnut Oak acorns setting roots into the leaf litter to secure their place among the plants that will turn the forest understory green in the spring.  Individual acorns that germinate soon after falling to the ground in autumn may avoid becoming food for squirrels, turkeys, deer, and other wildlife, thus increasing their chances of surviving to later become adult trees able to produce acorns that pass this quick-development trait to yet another generation of oaks.

Photo of the Day

Blue Wood Aster (Symphyotrichum cordifolium)
Among the hardy wildflowers still in bloom in the forests of the lower Susquehanna valley is the Blue Wood Aster (Symphyotrichum cordifolium), a variable species also known as the Heart-leaved Aster.

Photo of the Day

It looks like Uncle Tyler Dyer had a fun-filled Halloween.  Earlier this afternoon, we caught him drifting off into a nap during his work to make updates to his leaf scans.  As he snoozed away, we found these lying on the floor next to his easy chair and decided to lend a hand by adding them to his collection.  We’ll see how long it takes him to discover our dirty little deed.  You can have a look at our mischief by clicking on the “Trees, Shrubs, and Woody Vines” tab at the top of this page.

Big Winds Bring Big Birds

Colder temperatures and gusty northwest winds are prompting our largest migratory raptors to continue their southward movements.  Here are some of the birds seen earlier today riding updrafts of air currents along one of the Lower Susquehanna River Watershed’s numerous ridges.

Turkey Vulture
Hundreds of Turkey Vultures are presently passing through the lower Susquehanna valley on their way south.  Their winter abundance here is largely determined by the availability of carrion.
Hatch-year Bald Eagle
The late-season push of Bald Eagles is now underway.  Today, ten or more birds were seen at several of the region’s hawk watches.  This particular eagle is a juvenile, a hatch-year bird, with an unusually large area of white in the tail.
Red-tailed Hawks
Red-tailed hawks pass a hawk-counting station while gliding away to the southwest within an energy-saving updraft of ridge-deflected wind.
Golden Eagle and Red-shouldered Hawk
A migrating Golden Eagle keeps a wary eye on a marauding Red-shouldered Hawk.  This Golden Eagle is young, either in its hatch year or second year of life.
Red-tailed Hawk
A Red-tailed Hawk migrating during a late-afternoon snow shower.

As winter begins clawing at the door, now is great time to visit a hawk watch near you to see these late-season specialties.  Remember to dress in layers and to click the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab at the top of this page.  Hawkwatcher’s Helper is your guide to regional hawk watching locations and raptor identification.  Be sure to check it out.  And remember, it’s cold on top of those ridges, so don’t forget your hat, your gloves, and your chap stick!

If You’re Out Collecting Sweets, It Pays to Look Scary

Only fools mess around with bees, wasps, and hornets as they collect nectar and go about their business while visiting flowering plants.  Relentlessly curious predators and other trouble makers quickly learn that patterns of white, yellow, or orange contrasting with black are a warning that the pain and anguish of being zapped with a venomous sting awaits those who throw caution to the wind.  Through the process of natural selection, many venomous and poisonous animals have developed conspicuously bright or contrasting color schemes to deter would-be predators and molesters from making such a big mistake.

"Red Eft"
The brilliant colors of the “Red Eft”, the terrestrial sub-adult stage of the aquatic Eastern Newt (Notophthalmus viridescens), provide protection not as a form of camouflage, but as a warning to potential predators that “I am inedible” due to the presence of tetrodotoxin, a strong neurotoxin.  Over the generations, natural selection has better enabled the brightest of the individual “Red Efts” to survive to adulthood and reproduce.  Meanwhile, those efts that provided a less obvious visual clue to their toxicity frequently allowed their pursuer to learn of their defense mechanism by the taste-test method.  As one might expect, far fewer of these latter individuals survived to breed and pass along their more cryptic color variation.

Visual warnings enhance the effectiveness of the defensive measures possessed by venomous, poisonous, and distasteful creatures.  Aggressors learn to associate the presence of these color patterns with the experience of pain and discomfort.  Thereafter, they keep their distance to avoid any trouble.  In return, the potential victims of this unsolicited aggression escape injury and retain their defenses for use against yet-to-be-enlightened pursuers.  Thanks to their threatening appearance, the chances of survival are increased for these would-be victims without the need to risk death or injury while deploying their venomous stingers, poisonous compounds, or other defensive measures.

European Paper Wasp
Armed and Dangerous  The yellow-and-black color pattern on this European Paper Wasp signals a potential aggressor that they have come upon a social insect and could be struck with a venomous sting.  The warning colors alone may be all the defenses necessary for this wasp to survive an otherwise fatal encounter.

One shouldn’t be surprised to learn that over time, as these aforementioned venomous, poisonous, and foul-tasting critters developed their patterns of warning colors, there were numerous harmless animals living within close association with these species that, through the process of natural selection, acquired nearly identical color patterns for their own protection from predators.  This form of defensive impersonation is known as Batesian mimicry.

Let’s take a look at some examples of Batesian mimicry right here in the Lower Susquehanna River Watershed.

Suppose for a moment that you were a fly.  As you might expect, you would have plenty to fear while you spend your day visiting flowers in search of energy-rich nectar—hundreds of hungry birds and other animals want to eat you.

Greenbottle Fly
You might not hurt a fly, but plenty of other creatures will.  This Greenbottle Fly relies upon speed and maneuverability to quickly flee predators.
Common Flesh Fly (Sarcophaga species)
Like the Greenbottle Fly, the Common Flesh Fly (Sarcophaga species) needs to be constantly vigilant and survives by being quick to the wing.

If you were a fly and you were headed out and about to call upon numerous nectar-producing flowers so you could round up some sweet treats, wouldn’t you feel a whole lot safer if you looked like those venomous bees, wasps, and hornets in your neighborhood?  Wouldn’t it be a whole lot more fun to look scary—so scary that would-be aggressors fear that you might sting them if they gave you any trouble?

Suppose Mother Nature and Father Time dressed you up to look like a bee or a wasp instead of a helpless fly?  Then maybe you could go out and collect sweets without always worrying about the bullies and the brutes, just like these flies of the lower Susquehanna  do…

FLOWER FLIES/HOVER FLIES

The Common Drone Fly (Eristalis Tenax) is a Honey Bee mimic
The Common Drone Fly (Eristalis tenax) is an unarmed Honey Bee mimic.  This one is gathering nectar on goldenrod flowers.
Transverse Flower Fly (Eristalis transversa)
The Transverse Flower Fly (Eristalis transversa) is another bee mimic.  Members of the genus Eristalis scavenge carcasses in aquatic habitats.  Their larvae are known as rat-tailed maggots, a name that references their long siphons used for breathing surface air while submerged in ponds, streams, and wetlands.
Spilomyia species Flower Fly
Flower flies of the genus Spilomyia are convincing mimics of temperamental yellowjacket wasps.
Yellowjacket Hover Fly
The Yellowjacket Hover Fly (Milesia virginiensis) is usually heard long before it is seen.  It will often approach people and persist with a loud buzzing, sounding more like a bee than a bee does.  Scary, isn’t it?
 Maize Calligrapher
The Maize Calligrapher (Toxomerus politus) is a hover fly mimic of wasps.  Seen here on Indiangrass, it is believed to associate primarily with Corn (Zea mays).
The Narrow-headed Marsh Fly (Helophilus fasciatus) is a wasp mimic.
The Narrow-headed Marsh Fly (Helophilus fasciatus) is a wasp mimic.  Like other mimics of hymenopterans, they are important pollinators of flowering plants.
Syrphus species Hoverfly
This hover fly of the genus Syrphus is another wasp mimic.

TACHINID FLIES

The Feather-legged Fly (Trichopoda species) is a wasp mimic.
The Feather-legged Fly (Trichopoda species) is a wasp mimic.   Its larvae are parasitoids of stink bugs and leaf-footed bugs.

BEE FLIES

Bee Fly (Exoprosopa species)
Bee flies of the genus Exoprosopa convincingly resemble bumble bees.
Bee Fly (Exoprosopa species)
The larvae of Exoprosopa bee flies are believed to be parasitic on the larvae of the parasites of bee and wasp larvae that mature in the soil.  Confused yet?

So let’s review.  If you’re a poor defenseless fly and you want to get your fair share of sweets without being gobbled up by the beasts, then you’ve got to masquerade like a strongly armed member of a social colony—like a bee, wasp, or hornet.  Now look scary and go get your treats.  HAPPY HALLOWEEN!

Visit South Mountain for the Brightest Foliage Display You’ve Ever Seen

Where should you go this weekend to see vibrantly colored foliage in our region?  Where are there eye-popping displays of reds, oranges, yellows, and greens without so much brown and gray?  The answer is Michaux State Forest on South Mountain in Adams, Cumberland, and Franklin Counties.

South Mountain is the northern extension of the Blue Ridge Section of the Ridge and Valley Province in Pennsylvania.  Michaux State Forest includes much of the wooded land on South Mountain.  Within or adjacent to its borders are located four state parks: King’s Gap Environmental Education Center, Pine Grove Furnace State Park, Caledonia State Park, and Mont Alto State Park.  The vast network of trails on these state lands includes the Appalachian Trail, which remains in the mountainous Blue Ridge Section all the way to its southern terminus in Georgia.

Pennsylvania State Parks on South Mounatin
In Pennsylvania, the forested highlands of the Blue Ridge Section of the Ridge and Valley Province are known as South Mountain.  Much of South Mountain lies within the boundaries of Michaux State Forest.  Stars indicate the locations of 1) King’s Gap Environmental Education Center, 2) Pine Grove Furnace State Park, 3) Caledonia State Park, and 4) Mont Alto State Park.  A drive on US 30 between Gettysburg and Chambersburg will take you right through Michaux State Forest along an east to west axis while a scenic northbound or southbound trip along PA 233 will bring you in proximity to each of the state parks located therein.  (Base image from NASA Earth Observatory Collection)

If you want a closeup look at the many species of trees found in Michaux State Forest, and you want them to be labeled so you know what they are, a stop at the Pennsylvania State University’s Mont Alto arboretum is a must.  Located next door to Mont Alto State Park along PA 233, the Arboretum at Penn State Mont Alto covers the entire campus.  Planting began on Arbor Day in 1905 shortly after establishment of the Pennsylvania State Forest Academy at the site in 1903.  Back then, the state’s “forests” were in the process of regeneration after nineteenth-century clear cutting.  These harvests balded the landscape and left behind the combustible waste which fueled the frequent wildfires that plagued reforestation efforts for more than half a century.  The academy educated future foresters on the skills needed to regrow and manage the state’s woodlands.

Online resources can help you plan your visit to the Arboretum at Penn State Mont Alto.  More than 800 trees on the campus are numbered with small blue tags.  The “List of arboretum trees by Tag Number” can be downloaded to tell you the species or variety of each.  The interactive map provides the locations of individual trees plotted by tag number while the Grove Map displays the locations of groups of trees on the campus categorized by region of origin.  A Founder’s Tree Map will help you find some of the oldest specimens in the collection and a Commemorative Tree Map will help you find dedicated trees.  There is also a species list of the common and scientific tree names.

Yellow Buckeye
The Yellow Buckeye (Aesculus flava) is a tree found in the forests of the Blue Ridge Section of the Ridge and Valley Province in West Virginia, Virginia, North Carolina and Georgia.  You can see it in Pennsylvania by visiting the collection of trees in the Arboretum at Penn State Mont Alto.
American Chestnut
The American Chestnut can be difficult to find due to the impact of chestnut blight, but you can see it in the Arboretum at Penn State Mont Alto.
Shagbark Hickory
Shagbark Hickory is a common tree in the forests of South Mountain.
Sweet Cherry
The Sweet Cherry (Prunus avium), a native of Europe, is naturalized throughout eastern and south-central Pennsylvania and is one of the more than 150 species of trees in the arboretum’s collection.
Sweet Birch
Sweet Birch (Betula lenta) foliage is particularly bright yellow on South Mountain this autumn.  It really “pops” against the backdrop of the evergreen Eastern White Pines and Eastern Hemlocks.  During less-than-ideal years, Sweet Birch leaves can subtly transition from green to drab brown without much fanfare before falling.
Common Persimmon
You might have a difficult time finding a Common Persimmon (Diospyros virginiana) growing wild in Pennsylvania, but you can find it in the Arboretum at Penn State Mont Alto.

The autumn leaves will be falling fast, so make it a point this weekend to check out the show on South Mountain.

Fall Foliage at the Peak of Color

Have you noticed?  Foliage throughout the Lower Susquehanna River Watershed has been painted with the brilliant colors of autumn, so now is the time to get out there and have a look.  Why not make a collection?  You can pick up an inexpensive scrap book or photo album at the craft store to press and label the varieties you find.  Uncle Tyler Dyer is already busy adding to the project he assembled last year.  You can use his exhibit as a reference for identifying and learning a little bit more about the leaves you find.

To identify the leaves you discover, click this image.
Leaf Collection Mounted in a Photo Album
The editor’s 1995 collection of leaves from the Susquehanna River floodplain at Conewago Falls.

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.

Photo of the Day

Ruby-crowned Kinglet
With warbler migration winding down, it’s time to keep an eye open for the tiny kinglets, particularly in coniferous trees.  This Ruby-crowned Kinglet was spotted yesterday in the boughs of an Eastern Hemlock.  While common during autumn migration in October, only a few will remain in the Lower Susquehanna River Watershed for winter.

American Goldfinches Molting into Winter Plumage

Say it isn’t so.  Does summer really have to go?

Our brightly colored goldfinches are gone for the year.  No more Pennsylvania distelfinks glowing like bright-yellow Easter peeps on our feeders.  Oh, the birds are still here mind you, but their sunshine-gold feathers are falling away.  Because winter time is no time to show off.  One must blend in and maintain a low profile to conserve energy and avoid trouble as rough weather arrives.  So our American Goldfinches have commenced to molting—shedding their breeding plumes and replacing them with drab earth-tone shades for winter.

An adult male American Goldfinch losing its spectacular summer color and molting into less-than-thrilling winter feathers.
American Goldfinch in molt.
This ratty-looking adult male American Goldfinch is rapidly replacing its showy breeding (alternate) plumage with winter (basic) plumage.  A new set of wing feathers is readily visible.
Juvenile American Goldfinch
Juvenile American Goldfinches leave the nest with this first complete set of feathers.  Soon, adult birds will be wearing a similar color scheme.  Then, as spring approaches, they’ll all begin a gradual molt into the brilliant hues we all know and love.

Late Season Ruby-throated Hummingbirds…Again

Last October 3rd, a late-season Ruby-throated Hummingbird stopped by the garden at susquehannawildlife.net headquarters to take shelter from a rainy autumn storm.  It was so raw and chilly that we felt compelled to do something we don’t normally do—put out the sugar water feeder to supplement the nectar produced by our fall-flowering plants.  After several days of constant visits to the feeder and the flowers, our lingering hummer resumed its southbound journey on October 7th.

Fast forward to this afternoon and what do you know, at least two migrating hummingbirds have stopped by to visit the flowers in our garden.  This year, we have an exceptional abundance of blooms on some of their favorite plants.  In the ponds, aquatic Pickerelweed is topped with purple spikes and we still have bright orange tubular flowers on one of our Trumpet Vines—a full two to three months later than usual.

Late-season Ruby-throated Hummingbird
We checked each of our late-season visitors carefully to be reasonably certain that none was a stray western species of hummingbird.  All appear to be female or juvenile “Ruby-throats”.  If you have an abundance of flowering plants and/or you’re going to maintain your hummingbird feeders through the coming weeks, be on the lookout for western species.  Most are more hardy than our Ruby-throats and some have remained in the lower Susquehanna valley through the winter.
Ruby-throated Hummingbird at Mexican Cigar
As is typically the case, Ruby-throated Hummingbirds quickly gravitate toward the tubular flowers of our Cuphea ignea, the Mexican Cigar.  They find these showy plants to be absolutely irresistible.
Ruby-throated Hummingbird at Mexican Cigar
Mexican Cigar grows wild in parts of the Ruby-throated Hummingbird’s winter range.  To them, it’s comfort food.
Ruby-throated Hummingbird at Bat-faced Cuphea
We’re trying some new cultivars of Cuphea to see how they do.  As this composite image shows, the hummingbirds won’t let our Bat-faced Cuphea (Cuphea llavea) alone.  It’s another plant native to Mexico and Central America, right where some of our hummingbirds spend the winter.

Remember, keep those feeders clean and the provisions fresh!  You’ll be glad you did.

Hymanoptera: A Look at Some Bees, Wasps, Hornets, and Ants

What’s all this buzz about bees?  And what’s a hymanopteran?  Well, let’s see.

Hymanoptera—our bees, wasps, hornets and ants—are generally considered to be our most evolved insects.  Some form complex social colonies.  Others lead solitary lives.  Many are essential pollinators of flowering plants, including cultivars that provide food for people around the world.  There are those with stingers for disabling prey and defending themselves and their nests.  And then there are those without stingers.  The predatory species are frequently regarded to be the most significant biological controls of the insects that might otherwise become destructive pests.  The vast majority of the Hymanoptera show no aggression toward humans, a demeanor that is seldom reciprocated.

Late summer and early autumn is a critical time for the Hymanoptera.  Most species are at their peak of abundance during this time of year, but many of the adult insects face certain death with the coming of freezing weather.  Those that will perish are busy, either individually or as members of a colony, creating shelter and gathering food to nourish the larvae that will repopulate the environs with a new generation of adults next year.  Without abundant sources of protein and carbohydrates, these efforts can quickly fail.  Protein is stored for use by the larval insects upon hatching from their eggs.  Because the eggs are typically deposited in a cell directly upon the cache of protein, the larvae can begin feeding and growing immediately.  To provide energy for collecting protein and nesting materials, and in some cases excavating nest chambers, Hymanoptera seek out sources of carbohydrates.  Species that remain active during cold weather must store up enough of a carbohydrate reserve to make it through the winter.  Honey Bees make honey for this purpose.  As you are about to see, members of this suborder rely predominately upon pollen or insect prey for protein, and upon nectar and/or honeydew for carbohydrates.

We’ve assembled here a collection of images and some short commentary describing nearly two dozen kinds of Hymanoptera found in the Lower Susquehanna River Watershed, the majority photographed as they busily collected provisions during recent weeks.  Let’s see what some of these fascinating hymanopterans are up to…

SOLITARY WASPS

Great Black Wasp on goldenrod (Solidago species)
A Great Black Wasp on goldenrod (Solidago species).  Like other solitary wasps, a female  Great Black Wasp will sting and paralyze a host insect upon which she’ll deposit her eggs.  After hatching, the larvae will begin consuming the host’s body as a source of protein.  The parasitized insects are often katydids or grasshoppers.
A Great Black Wasp.
A Great Black Wasp feeding on nectar, a source of carbohydrates.  Unlike social bees and wasps, solitary wasps are equipped with a stinger solely used for immobilizing prey, not defending a nest.  They are therefore quite docile and pose little threat to humans.
A Great Black Wasp powdered with pollen.
A Great Black Wasp powdered with pollen.  Hymanopterans that gather nectar and/or pollen are tremendously important pollinators of hundreds of species of plants.
Thread-waisted Wasp
A female Thread-waisted wasp (Ammophilia species, probably A. nigricans) drags a paralyzed caterpillar to her excavated nest where she’ll deposit an egg on the body.  After hatching, the larval wasp will feed on the disabled caterpillar.  The protein will enable the larvae to grow, pupate, and later emerge as an adult wasp.
The female Eastern Cicada Killer (Sphecius speciosus) excavates an underground nest with branch tunnels connecting a dozen chambers or more.  As the common name suggests, the female wasp paralyzes a cicada, then makes a strenuous effort to fly and drag it back to the nest for placement in a cell.  Each male wasp egg is deposited upon just one immobilized cicada, but a female egg is provided with a cache of several cicadas to provide adequate protein for growth to a larger size.  Nest cells are sealed with soil, then the larvae hatch in just a couple of days.  Within about two weeks, they have consumed the cicada protein and are fully grown.  Wrapped in a cocoon, they spend the winter in the nest, then pupate in the spring before emerging as a new generation of adults.
The Black-and-yellow Mud Dauber
The Black-and-yellow Mud Dauber (Sceliphron caementarium) builds a mud-ball nest within which it packs paralyzed spiders to function as a source of protein for its larvae.
Black-and-yellow Mud Dauber at nest.
A Black-and-yellow Mud Dauber at nest.
Pipe Organ Mud Dauber Nest
The Pipe Organ Mud Dauber builds this elaborate nest in which their eggs and paralyzed spiders are deposited in cells sealed with mud partitions.  After consuming the spiders, the larvae pupate, overwinter, then emerge from their cells as adults during the following spring.  To escape the protection of the nest, the new generation of adults bore through the mud walls.  Adult Pipe Organ Mud Daubers resemble the Great Black Wasp, but have a white or yellow distal segment on their rear legs resembling a pair of light-colored socks.
A closeup of the previous image with the lengths of the nest tubes compressed to show four scavenger flies (Miltogramminae), possibly two species, that have invaded this Pipe Organ Mud Dauber nest.  Scavenger flies are kleptoparasites that victimize various solitary bees and wasps, depositing larvae directly into the host species’ nest cells to consume the protein cache stored therein.

CUCKOO WASPS

Cuckoo Wasp
Cuckoo Wasps (Chrysididae), also known as Emerald Wasps, parasitize the nests of other species of wasps.  Females lay their eggs inside the host’s nest, then flee the scene.  Upon hatching, larval Cuckoo Wasps feed on stockpiles of prey intended for the host species’ offspring.  Like the adult mud daubers that have already matured and departed this nest by digging a hole through the wall of the cell within which they were hatched, the metallic green Cuckoo Wasp in the upper left has just emerged in much the same way.

SWEAT BEES

A Sweat Bee (Lasioglossum species).
A Sweat Bee (Lasioglossum species) collecting nectar and pollen on White Snakeroot (Ageratina altissima).
A Sweat Bee (Lasioglossum species).
Sweat Bees (Lasioglossum species) visit human skin to lick up the electrolytes left behind by evaporating perspiration.
A Sweat Bee (Lasioglossum species).
Sweat Bees  in the genus Lasioglossum demonstrate various social behaviors ranging from species that are solitary nesters to those that create colonies with work forces ranging in size from as few as four to as many as hundreds of bees.  Some Lasioglossum practice kleptoparasitism, while others are quite accomplished foragers.
An Augochlorine Green Sweat Bee (Augochlorini).
A female Augochlorine Green Sweat Bee (Augochlorini) collecting nectar on White Snakeroot.  Notice the pollen “baskets” on the rear leg.
An Augochlorine Green Sweat Bee (Augochlorini).
An Augochlorine Green Sweat Bee (Augochlorini).  Sweat bees nest in subterranean cavities and in hollowed out sections of trees.
An Augochlorine Green Sweat Bee (Augochlorini).
A copper-colored Augochlorine Green Sweat Bee (Augochlorini) collecting nectar and dusted with pollen.

LEAFCUTTER AND MASON BEES

Leafcutter Bee
A Leafcutter Bee (Megachile species).  Like Mason Bees, female Mason Bees deposit each of their eggs on a “pollen loaf” within an individual cell inside a preexisting tunnel-like cavity in wood, stone, or in the ground.  Unlike Mason Bees, female Leafcutter Bees cut a circular piece of leaf to create each of the cells in their nest.  After hatching, the larval bee feeds on the pollen loaf, pupates, then emerges from the shelter of the nest to start a new generation, usually during the following year.
A Leafcutter Bee (Megachile species).
A Leafcutter Bee (Megachile species) visiting Wild Bergamot.  Female Leafcutter and Mason Bees lack pollen “baskets” on their rear legs but instead have pollen “brushes” on the underside of the abdomen to gather the protein they need to create a “pollen loaf” for each nest cell.
Leafcutter Bee
A Leafcutter Bee (Megachile species) collecting nectar from White Snakeroot.
A Mason Bee (Osmia species) emerging from a nest cell in spring.
A Mason Bee (Osmia species) emerging from a nest in spring.  Mason Bees create nesting cells within preexisting cavities in wood, stone, and other other supporting structures.  Within the nest cavity, each egg is deposited atop a cache of pollen and nectar, a pollen loaf, then enclosed behind a partition of mud.  The female Mason Bee will usually repeat this process until an entire cavity is filled with cells.  During the following spring, a new generation of adult Mason Bees digs its way through the cell walls to emerge and repeat the process.  These bees readily use paper straws or holes drilled in blocks of wood for nesting.
A mason bee nest box with holes drilled into blocks of wood.
A mason bee nest box with holes drilled into blocks of wood.
Parasitized Mason Bee Nest
Mason Bees seal each cell and the outer end of their nest cavity with mud.  These outer nest cells can been parasitized by a variety of wasps.  Here, the outer cell of a Mason Bee nest has been victimized by a tiny chalcid wasp (looks like another one to the lower left).  Several species of female chalcid wasps (native Monodontomerus species or non-native Pteromalus venustus) enlarge weak points in the outer partition of a mason bee nest, then sting and paralyze the larval bee inside before depositing their eggs.  Within the cell. the wasp larvae consume the larval Mason Bee and the “pollen loaf” provided for its growth.  These same parasitic wasps prey upon Leafcutter Bees as well.

BUMBLE BEES, CARPENTER BEES, HONEY BEES, AND DIGGER BEES

Common Eastern Bumble Bee
A Common Eastern Bumble Bee (Bombus impatiens) collecting nectar and pollen on goldenrod.  Bumble bees are our sole native group of social bees.  Their wax nests are built in a burrow or other shelter.  The eggs are deposited in cells along with a supply of pollen for nourishing the larvae upon hatching.  Honey is stored in “honey pots” within the nest.  New queens are produced along with male bees during the late-summer and fall.  Only the new generation of fertilized queens survive the winter to lay eggs and produce workers to construct a new nest.
Common Eastern Bumble Bees
A pair of Common Eastern Bumble Bees collecting nectar and becoming dusted with pollen.  Their fuzzy coats and semi-warm-blooded metabolism allows them to be active in cooler weather than is tolerated by other bees.
A Common Eastern Bumble Bee pollinating a Great Rhododendron flower.
Flowering plants including the Great Rhododendron find success attracting pollinators to their reproductive blossoms by offering carbohydrate-rich nectar to insects like this Eastern Bumble Bee.  The yellow spots on the flower’s upper petal help to guide visitors toward their sweet treat.
Eastern Carpenter Bee
An Eastern Carpenter Bee feeding on goldenrod nectar.  Compare the almost hairless abdomen to that of the bumble bees.  Carpenter bees are semi-social insects.  Females lay their eggs in cells within galleries bored into wood.  These nests are completed with great precision, avoiding creation of any second entrance by mistakenly breaching the outer surface of the excavated wood.  Each egg/larvae is provided with a supply of protein-rich pollen.  Males often hover outside their mate’s nest to prevent competing males from entering the area.
A Honey Bee visiting goldenrod alongside Common Eastern Bumble Bees.
A worker Honey Bee, a female member of a sisterhood of foragers from a nearby hive, visits goldenrod alongside Common Eastern Bumble Bees.  Honey Bees were brought to North America during the 1620s, the earliest years of the trans-Atlantic migration of European colonists, to pollinate cultivated plants and to provide a reliable source of honey and beeswax.  Within the Honey Bee’s social structure, the queen of each hive lays the eggs to produce the female worker bees.  Once each year, male drones are produced along with a new generation of queens.
Honey Bee Hive
In nature, Honey Bees build hives in tree cavities.  Recently, this colony constructed a hive in a screech owl nest box at susquehannawildlife.net headquarters.  To provide protein for the hatching larvae, worker bees collect pollen and deposit it within the hexagonal cells of the vertically aligned beeswax combs.  After an egg is deposited upon the pollen cache, each cell is sealed with more beeswax.  Young females tend these nest combs before maturing and becoming foraging worker bees.
Bee Hive Display
In apiculture, Honey Bees are raised in man-made hives.  This Pennsylvania Association of Beekeepers display gives visitors to the Pennsylvania Farm Show in Harrisburg a look at the inner workings of a live bee hive.  Nectar collected by worker bees is turned into honey to provide the supply of carbohydrates needed to fuel the colony through the winter.  Note the honeycombs on the glass.
A possible Small Carpenter Bee Ceratina species).
A possible Small Carpenter Bee (Ceratina species) visiting White Snakeroot.  Small Carpenter Bees nest inside hollow stems and twigs.  Some species are eusocial, with a queen’s daughters and sisters sharing responsibility for finding food and rearing the young.  Females overwinter inside a one of the excavated stems and begin a new nest there in the spring.
A Digger Bee (possibly Melissodes species).
A Digger Bee (possibly Melissodes species) with “pollen baskets” full of pollen collected from nearby flowers.  Digger Bees in the genus Melissodes are often known as the Long-horned Bees.  These social insects excavate underground nests and many species practice communal living.

SCOLIID WASPS

Two-spotted Scoliid Wasp
The Two-spotted Scoliid Wasp (Scolia dubia), also known as the Blue-winged Scoliid Wasp, is most frequently observed feeding on nectar.  Scoliid wasps are solitary nesters, though they may assemble into groups while visiting flowers.  They often ignore the presence of humans and are seldom disturbed by their presence.  Females seek out the burrowing grubs of beetles including the Green June Bug (Cotinis nitida) and possibly the Japanese Beetle.  After stinging a grub to paralyze it, the wasp will deposit her egg on its body, then bury it.  Upon hatching, the larval wasp will feed on the grub for nourishment as it grows.
June Bugs eating watermelon.
Don’t like having your watermelon overrun by Green June Bugs while you’re eating?  Then you ought to go out of your way to be nice to the Two-spotted Scoliid Wasp.
The Double-banded Scoliid
The Double-banded Scoliid (Scolia bicincta) parasitizes beetle larvae as hosts for its larvae.  For carbohydrates it relishes flower nectar.

PAPER WASPS

Northern Paper Wasp
A Northern Paper Wasp (Polistes fuscatus).  Paper wasps prey upon numerous garden pests, particularly caterpillars, to collect protein.  Though they are social insects equipped with stingers to subdue their victims and defend their nests, paper wasps are surprisingly docile.
The Northern Paper Wasp
A Northern Paper Wasp (Polistes fuscatus) feeding on nectar from a goldenrod flower.
A Northern Paper Wasp harvesting wood pulp
A Northern Paper Wasp harvesting wood pulp from the side of a mason bee nest box at susquehannawildlife.net headquarters.  The pulp is chewed in the wasp’s saliva to create the paper used to construct the colony’s open-cell nest.
Guinea Paper Wasps (Polistes exclamans) at their nest.
Common Paper Wasps (Polistes exclamans), also known as Guinea Paper Wasps, at their open-cell nest.  This and the nests of most other paper wasps are suspended on a filament or a pedicle.  Many paper wasps can excrete an ant repellent on this section of the nest in an effort to prevent invasion.  Like many other social hymenopterans, a defending wasp can secrete a pheromone venom during the stinging process to warn the colony of danger at the nest.  In winter, Common Paper Wasps seek shelter in stumps and other locations to hibernate.
European Paper Wasp
The European Paper Wasp (Polistes dominula) is a non-native species which builds nests in man-made structures including bird houses.  To collect protein, they prey on a wide selection of insects and other invertebrates.  As such, European Paper Wasps are widespread and successful here in North America.

YELLOWJACKETS AND HORNETS

An Eastern Yellowjacket
An Eastern Yellowjacket feeding on lanternfly honeydew.  Eastern Yellowjackets derive much of their success from being generalists, collecting carbohydrates from nearly any sweet source, natural or man made.  They are quite fond of ripe fruits, flower nectar, and sugary snacks and drinks, especially soda.  Protein for nourishing their larvae is derived from the wide variety invertebrates upon which they prey and from carrion.  These foods are chewed into a paste form in preparation for placement into the brood cells.
An Eastern Yellowjacket.
A subterranean colony of Eastern Yellowjackets is started anew each spring by a young queen that has survived winter hibernation in diapause, a state of interrupted development.  She constructs the new nest’s first cells using pulp made by chewing rotting wood.  The first brood of workers scales up construction while the queen continues producing eggs.  At the nest, these social insects will viciously attack anyone or anything perceived to be a threat, so give them their space and leave them alone.  Many yellowjacket infestations of homes and other buildings are the work of non-native German Yellowjacket (Vespula germanica) [not shown], an invasive species that constructs paper nests in void spaces including walls and attics.
Robber Fly consuming an Eastern Yellowjacket
Yellowjackets may be moody and aggressive, but they do fall victim to a number of predators.  A Robber Fly (Promachus species) has taken down and is devouring this Eastern Yellowjacket.
A Bald-faced Hornet (Dolichovespula maculata) feeding on Spotted Lanternfly honeydew deposits
A Bald-faced Hornet (Dolichovespula maculata) feeding on Spotted Lanternfly honeydew on a Tree-of-heaven (Ailanthus altissima).  In the absence of nectar-producing flowers, many bees, yellowjackets, and hornets have turned to the invasive lanternfly and Ailanthus combo to turn the sun’s energy into the carbohydrates they need.  For protein, they prey upon spiders, flies, caterpillars, and a variety of other insects.
A Bald-faced Hornet collecting wood pulp from the surface of a weathered picnic table.
To create paper for nest construction, this Bald-faced Hornet is collecting wood pulp from the surface of a weathered picnic table.  Away from the nest, these hornets demonstrate a calm, carefree demeanor and can be closely observed.
Bald-faced Hornet Nest
A Bald-faced Hornet nest in a pine tree.  These hives are strictly temporary.  Within the nest, a generation of drones (males) and new queens are produced late each year.  These wasps leave the colony to mate.  With the arrival of freezing weather, all inhabitants within the nest, including the old queen, perish, as do the drones that departed to breed.  Only the new queens survive winter hibernation to propagate the next generation of wasps,  starting with the workers needed to construct a fresh nest and reestablish the colony.
Bald-faced Hornets Peering from Nest
Did you ever get the feeling you’re being watched?  Don’t go messing around with Bald-faced Hornet nests.  The occupants therein, like other social bees, wasps, and hornets, are equipped with stingers and venom for defending their colony.  This is an adaptation that has developed over time to assure the survival of populations of these insects.  Think about it this way, a solitary wasp that loses a nest loses only their individual brood of offspring.  There is minimal impact on the wider local population of such insects.  Conversely, a social wasp or hornet that loses a nest loses an entire colony, possibly negating the benefits of their cooperative behavior and threatening the survival of the species.  Insects that cooperate to build societies for survival can be more vulnerable to the catastrophic impacts of certain circumstances like disease, weather, and invasion of their colonies.  Therefore, natural selection has provided them with contingencies for these dangers, for example, the instinct to construct protective shelters and the adaptation of stingers and venom for defense against intruders and would-be predators.  Oh, and by the way, the Bald-faced Hornet can spray venom, often aiming for the eyes, so keep your distance.
European Hornets
European Hornets (Vespa crabro), an introduced species, are predatory on a variety of flying insects for protein.  For carbohydrates they are attracted to sweets like this lanternfly honeydew on Tree-of-heaven.
European Hornets constructing a nest in a tree cavity.
European Hornets constructing a paper nest in a tree cavity.

POTTER WASPS

A Potter Wasp (Eumenes species, probably E. fraturnus) hovering near a European Paper Wasp.
A potter wasp (Eumenes species), probably a Fraternal Potter Wasp (E. fraternus), hovering near a European Paper Wasp on Partridge Pea.  The female potter wasp builds a small mud nest resembling a tiny clay pot.  One of her eggs is inserted and left hanging on a thin thread.  Then a paralyzed caterpillar is deposited as a source of protein to nourish the larva upon hatching.  Lastly, the pot is sealed with a lid made of wet mud.  Upon maturing, the new generation of adult wasps perform a pottery breaking to emerge and take flight.

ANTS

Field Ants (Formica species, possibly Formica pallidefulva) clearing the entrance to their underground nest.
Field Ants (Formica species, possibly Formica pallidefulva) clear the entrance to their underground nest.  Field ants are eusocial insects, they work in concert to build, maintain, and defend the nest, rear young, and find food.  There is no social caste system.  Field Ants are predators and scavengers when collecting protein.  For carbohydrates they often rely on the honeydew produced by aphids.  As a method of improving and sustaining the production of honeydew, some ant species will tend colonies of aphids by moving the younger individuals from depleted portions of plants to more healthy tissue.  Field Ant nests contain chambers used for a variety of functions including raising young and storing food.  Some nests include multiple queens and some colonies consist of more than one nest.   Ants in the genus Formica are weaponized; they can spray formic acid to repel intruders and defend their colony.

We hope this brief but fascinating look at some of our more common bees, wasps, hornets, and ants has provided the reader with an appreciation for the complexity with which their food webs and ecology have developed over time.  It should be no great mystery why bees and other insects, particularly native species, are becoming scarce or absent in areas of the Lower Susquehanna River Watershed where the landscape is paved, hyper-cultivated, sprayed, mowed, and devoid of native vegetation, particularly nectar-producing plants.  Late-summer and autumn can be an especially difficult time for hymanopterans seeking the sources of proteins and carbohydrates needed to complete preparations for next year’s generations of these valuable insects.  An absence of these staples during this critical time of year quickly diminishes the diversity of species and begins to tear at the fabric of the food web.  This degradation of a regional ecosystem can have unforeseen impacts that become increasingly widespread and in many cases permanent.

A farmland desert.

A farmland desert.
How can anyone be surprised by the absence of bees and other pollinators in farmland? Manicured and cultivated ground offers little in the way of year-round shelter and food sources for insects and other wildlife.
A savanna-like habitat.
This savanna-like habitat on a south-facing slope provides the abundance of nectar-producing, pollen-rich wildflowers needed to nourish a diverse population of insects including bees, wasps, hornets, and ants.  Goldenrods, asters, and White Snakeroot are some of their late-season favorites.

Editor’s Note: No bees, wasp, hornets, or ants were harmed during this production.  Neither was the editor swarmed, attacked, or stung.  Remember, don’t panic, just observe.

SOURCES

Eaton, Eric R., and Kenn Kaufman.  2007.  Kaufman Field Guide to Insects of North America.  Houghton Mifflin Company.  New York, NY.

(If you’re interested in insects, get this book!)

Photo of the Day

Eastern Palm Warbler
A warbler found moving through trees and shrubs or foraging on the ground while bobbing its tail is likely to be a Palm Warbler.  During migration, these animated passerines favor the vegetated shorelines of lakes, rivers, streams, and ponds.  This affinity for water is reflected in the Palm Warbler’s choice of breeding habitat.  Nesting territories are primarily located within spruce bogs east of the Rockies in Canada, Minnesota, Maine, and on the Upper Peninsula of Michigan.  The bird seen here with extensive yellow underparts is known as a Yellow or Eastern Palm Warbler (Setophaga palmarum hypochrysea), a subspecies that nests in eastern portions of the breeding range.  The duller, grayer Brown or Western Palm Warbler (S. p. palmarum) nests in western sections of the summer range.  In the Lower Susquehanna River Watershed, both subspecies can be seen during fall migration, which peaks in late September and October as movements of the less hardy Neotropical warblers are winding down.  Both subspecies spend the winter on Caribbean islands or in coastal plain areas of eastern North America.  Some of the western birds pass the colder months along the Pacific coast.

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.

Photo of the Day

Northern Ring-necked Snake shedding old skin.
For this Northern Ring-necked Snake (Diadophis punctatus edwardsii), they’ll be no hunting crickets, grasshoppers, and creepy crawlies under rocks and leaves for a little while.  It’s blind as a bat and finding its way by tongue and touch while beginning the process of shedding its skin so it can grow just a little bit bigger before heading underground for winter.