Eagle Time on the Ridges and River

As we enter November, migratory raptor flights through the Lower Susquehanna River Watershed transition to the bigger birds.  Whether you’re on the river, on a mountain, or just outside your humble abode, persistent alertness to soaring avians can yield rewarding views of a number of late-season specialties.

Red-tailed Hawk
Red-tailed Hawks dominate the southbound raptor flights in November.
Juvenile Red-tailed Hawk
Juvenile (hatch-year) Red-tailed Hawks are generally less wary and more inquisitive than the more experienced adult birds.  Their curiosity frequently gets them into trouble, particularly when they try to hunt small rodents in traffic along busy roadways.
Adult Red-shouldered Hawk
Far fewer in number are migratory Red-shouldered Hawks.  In our region, these denizens of bottomland forests more commonly migrate along the southern edge of the Piedmont and through the upper Atlantic Coastal Plain.
A hatch-year (juvenile) Red-shouldered Hawk
A southbound hatch-year (juvenile) Red-shouldered Hawk.
Peregrine Falcon
Mixed-race Peregrine Falcons, the descendants of birds reintroduced into the Mid-Atlantic States during the late twentieth century, often roam our region during the late-fall and winter months before settling into their nesting territories with the approach of spring.  We spotted this one along a local ridge, but you may be more likely to see them in the city or near a bridge or dam on the river.
Peregrine Falcon
As this adult peregrine passed the lookout, we noted its full crop.  A sign it just completed a successful hunt.

A visit to a ridgetop on a breezy day—particularly after passage of a cold front—may give you the chance to see numerous eagles as well.

A second-year (Basic I) Bald Eagle rolls over while pursuing an adult Bald Eagle.
A second-year (Basic I) Bald Eagle barrel rolls while pursuing an adult Bald Eagle.

This afternoon, we got lucky and were treated to a bit of an aging clinic presented by the Bald Eagles we observed and photographed.  Careful determination of the age classes of raptors counted by hawkwatchers can provide an early warning of problems in the ecosystems that support populations of these top-of-the-food-chain predators.  For example: during the 1950s and early 1960s, a progressively lower percentage of juvenile and other non-adult age classes among the Bald Eagles being observed forewarned of the dangers of dichlorodiphenyltrichloroethane (DDT) pesticide in the environment.  The principle effect of accumulations of the DDT toxins in eagles, Ospreys, Peregrine Falcons, and other predatory birds that consumed waterfowl and/or fish was to thin their eggs shells.  The result was widespread brood failure and a near total loss of new generations of offspring.  Eventually, nearly all Bald Eagles being seen in areas impacted by DDT were progressively older adults, most of which failed as nesting pairs.  As the adult birds began dying off, the Bald Eagle population dwindled to numbers that raised fears of the species’ extinction.  Implementation of the DDT cancellation order and the Clean Water Act in 1972, and the Endangered Species Act in 1973, helped save the Bald Eagle.  But our regional “Eastern Peregrine Falcon”, a bird with a shorter life span than the Bald Eagle, was unable to endure the years of DDT use, dioxin pollution, and illegal hunting and egg collecting.  Its population is gone.

Hatch-year Bald Eagle
A hatch-year (juvenile) Bald Eagle is typically dark headed and in a fresh set of juvenile flight feathers that exhibit no signs of molt.  If the reproduction season and the months that followed were favorable for this year’s brood of new eagles, there should be nearly as many hatch-year birds as there are adults in an overall population.
Second-year Bald Eagle
By November, second-year (Basic I) Bald Eagles are replacing many of their flight feathers and often show ragged trailing edges in the wings due to the retention of some of the well-worn and notably longer juvenile feathers.  Varying amounts of white mottling are visible on the breast, belly, and underwing coverts.  Due to mortality, there are usually fewer second-year Bald Eagles than there are hatch-year or adult birds.
Second-year (Basic I) Bald Eagle.
Another example of a second-year (Basic I) Bald Eagle.
Third-year Bald Eagle
Third-year (Basic II) Bald Eagles show more yellow in the bill and an “osprey face”, a white head with a wide dark line through the eye.  Most of the juvenile flight feathers have been replaced, so the wing edges appear more uniform.  Like the second-year eagles, there is a varying amount of white in the breast, belly, and underwing coverts.  In an overall population of eagles, birds in this age class are usually less common than those that are younger or those that are adults.
Bald Eagle Age Classes: First Three Years
Composite image of Bald Eagles in typical November plumage during their first three years.  To see more images like this, be certain to click the “Hawkwatcher’s Helper: Identifying Bald Eagles and other Diurnal Raptors” tab at the top of this page.
Fourth-year Bald Eagle
A fourth year (Basic III) Bald Eagle will often be seen with a black-bordered tail and a thin dark line through the eye.  In some birds, traces of these traits can linger into the fifth year and beyond.  These plumage types are usually the least frequently observed among an overall population of Bald Eagles.  (Note:  In these older birds, there develops significant variation in the timing of feather molt.  In rare cases, fourth-year Bald Eagles may show minimal dark color in the tail or eye line and may appear to be in near definitive adult plumage.)
A possible fifth-year (Basic IV) Bald Eagle.
A possible fifth-year (Basic IV) Bald Eagle.
Adult Bald Eagles in definitive plumage. 
Adult Bald Eagles in definitive plumage.  Birds in this plumage class are often the most frequently observed because the group includes all eagles five or six years of age and older.

While the Bald Eagles are still stealing the show, cold and gusty weather should bring an increasing number of Golden Eagles our way during the remainder of the month.  Some are already trickling through…

A "before-third-year" Golden Eagle.
This “before-third-year” Golden Eagle shows no visible signs of molt in its juvenile (hatch-year) plumage, but a look at the upperwing coverts is needed to properly age the bird.  To learn more about the molt sequence in Golden Eagles, be sure to click the “Golden Eagle Aging Chart” tab at the top of this page.
A "before-third-year" Golden Eagle passing the lookout along with a second-year Bald Eagle.
A “before-third-year” Golden Eagle (top) passing the lookout along with a second-year Bald Eagle (bottom).
"Before-third-year" Golden Eagle.
Another “before-third-year” Golden Eagle.  More are on the way!

Later this month, Bald Eagle numbers on the lower Susquehanna below Conowingo Dam (U.S. 1) near Rising Sun, Maryland, will begin to grow.  Fisherman’s Park, located along the west shoreline below the dam, is an excellent place to observe and photograph scores of these regal birds.  And few places provide a better opportunity to learn to differentiate Bald Eagle age classes.  If you’re really lucky, a Golden Eagle or two may drop in as well.  So plan to make the trip.  The best time to visit is on a weekday.  The parking lot can become overcrowded on weekends and will be closed under such circumstances.  It’s best to avoid the long Thanksgiving weekend as well.

Migrating Adult Bald Eagles
Remember to always look up.

Four Common Grasshoppers

Grasshoppers are perhaps best known for the occasions throughout history when an enormous congregation of these insects—a “plague of locusts”—would assemble and rove a region to feed.  These swarms, which sometimes covered tens of thousands of square miles or more, often decimated crops, darkened the sky, and, on occasion, resulted in catastrophic famine among human settlements in various parts of the world.

The largest “plague of locusts” in the United States occurred during the mid-1870s in the Great Plains.  The Rocky Mountain Locust (Melanoplus spretus), a grasshopper of prairies in the American west, had a range that extended east into New England, possibly settling there on lands cleared for farming.  Rocky Mountain Locusts, aside from their native habitat on grasslands, apparently thrived on fields planted with warm-season crops.  Like most grasshoppers, they fed and developed most vigorously during periods of dry, hot weather.  With plenty of vegetative matter to consume during periods of scorching temperatures, the stage was set for populations of these insects to explode in agricultural areas, then take wing in search of more forage.  Plagues struck parts of northern New England as early as the mid-1700s and were numerous in various states in the Great Plains through the middle of the 1800s.  The big ones hit between 1873 and 1877 when swarms numbering as many as trillions of grasshoppers did $200 million in crop damage and caused a famine so severe that many farmers abandoned the westward migration.  To prevent recurrent outbreaks of locust plagues and famine, experts suggested planting more cool-season grains like winter wheat, a crop which could mature and be harvested before the grasshoppers had a chance to cause any significant damage.  In the years that followed, and as prairies gave way to the expansive agricultural lands that presently cover most of the Rocky Mountain Locust’s former range, the grasshopper began to disappear.  By the early years of the twentieth century, the species was extinct.  No one was quite certain why, and the precise cause is still a topic of debate to this day.  Conversion of nearly all of its native habitat to cropland and grazing acreage seems to be the most likely culprit.

The critically endangered Eskimo Curlew (Numenius borealis), a species not photographed since 1962 and not confirmed since 1963, fed on Rocky Mountain Locusts during its spring migration through the Great Plains.  Excessive hunting and conversion of grasslands to agriculture are believed responsible for the bird’s demise.  (United States Fish and Wildlife Service image by Christina Nelson)

In the Mid-Atlantic States, the mosaic of the landscape—farmland interspersed with a mix of forest and disturbed urban/suburban lots—prevents grasshoppers from reaching the densities from which swarms arise.  In the years since the implementation of “Green Revolution” farming practices, numbers of grasshoppers in our region have declined.  Systemic insecticides including neonicotinoids keep grasshoppers and other insects from munching on warm-season crops like corn and soybeans.  And herbicides including 2,4-D (2,4-Dichlorophenoxyacetic acid) have, in effect, become the equivalent of insecticides, eliminating broadleaf food plants from the pasturelands and hayfields where grasshoppers once fed and reproduced in abundance.  As a result, few of the approximately three dozen species of grasshoppers with ranges that include the Lower Susquehanna River Watershed are common here.  Those that still thrive are largely adapted to roadsides, waste ground, and small clearings where native and some non-native plants make up their diet.

Here’s a look at four species of grasshoppers you’re likely to find in disturbed habitats throughout our region.  Each remains common in relatively pesticide-free spaces with stands of dense grasses and broadleaf plants nearby.

CAROLINA GRASSHOPPER

Dissosteira carolina

Carolina Grasshopper
The Carolina Grasshopper, also known as the Carolina Locust or Quaker, is one of the band-winged grasshoppers.  It is commonly found along roadsides and on other bare ground near stands of tall grass and broadleaf plants.
Carolina Grasshopper
The Carolina Grasshopper is variable in color, ranging from very dark brown…
Carolina Grasshopper
…to a rich tan or khaki shade.  These earth-tone colors provide the insect with effective camouflage while spending time on the ground.
Carolina Grasshopper wing
The Carolina Grasshopper is most readily detected and identified when it flies.  The colors of the wings resemble those of the Mourning Cloak butterfly.
Great Black Wasp on goldenrod.
Carolina Grasshoppers are among the preferred victims of Great Black Wasps (Sphex pensylvanicus).  A female wasp stings the grasshopper to paralyze it, then drags it away to one of numerous cells in an underground burrow where she lays an egg on it.  The body of the disabled grasshopper then provides nourishment for the larval wasp.

DIFFERENTIAL GRASSHOPPER

Melanoplus differentialis

Differential Grasshopper nymph.
Differential Grasshopper nymph with small “fairy wings”.
Differential Grasshopper
An adult female Differential Grasshopper with fully developed wings.
An adult female Differential Grasshopper
An adult female Differential Grasshopper

TWO-STRIPED GRASSHOPPER

Melanoplus bivittatus

Two-striped Grasshopper nymph.
An early-stage Two-striped Grasshopper nymph.
Two-striped Grasshopper nymph.
A Two-striped Grasshopper nymph in a later stage.
Two-striped Grasshopper
An adult female Two-striped Grasshopper.
Two-striped Grasshopper
An adult female Two-striped Grasshopper.  Note the pale stripe originating at each eye and joining near the posterior end of the wings to form a V-shaped pattern.
Two-striped Grasshopper
An adult female Two-striped Grasshopper.

RED-LEGGED GRASSHOPPER

Melanoplus femurrubrum

A Red-legged Grasshopper hiding in dense urban vegetation.
An adult male Red-legged Grasshopper hiding in dense urban vegetation.
Red-legged Grasshopper
The Red-legged Grasshopper may currently be our most abundant and widespread species.
Red-legged Grasshopper
An adult male Red-legged Grasshopper.
Red-legged Grasshopper
An adult female Red-legged Grasshopper.

Protein-rich grasshoppers are an important late-summer, early-fall food source for birds.  The absence of these insects has forced many species of breeding birds to abandon farmland or, in some cases, disappear altogether.

Beginning in the early 1930s, the Western Cattle Egret (Bubulcus ibis), a notoriously nomadic species, transited the Atlantic from Africa to colonize the Americas…and they did it without any direct assistance from humans.  During the 1970s and early 1980s, a nesting population of Western Cattle Egrets on river islands adjacent to the Susquehanna’s Conejohela Flats off Washington Boro was the largest inland rookery in the northeastern United States.  The Lancaster County Bird Club censused the birds each August and found peak numbers in 1981 (7,580).  During their years of abundance, V-shaped flocks of cattle egrets from the rookery islands ventured into grazing lands throughout portions of Lancaster, York, Dauphin, and Lebanon Counties to hunt grasshoppers.  These daily flights were a familiar summertime sight for nearly two decades.  Then, in the early 1980s, reductions in pastureland acreage and plummeting grasshopper numbers quickly took their toll.  By 1988, the rookery was abandoned.  The cattle egrets had moved on.  (Vintage 33 mm image)
During the summer and early fall, juvenile and adult Ring-necked Pheasants feed heavily on grasshoppers.  Earlier and more frequent mowing along with declining numbers of grasshoppers on farmlands due to an increase in pesticide use were factors contributing to the crash of the pheasant population in the early 1980s.
Wild Turkey
To the delight of Wild Turkeys, each of the four species of grasshoppers shown above frequents clearings and roadsides adjacent to forest areas.  While changes in grasshopper distribution have been detrimental to populations of birds like pheasants, they’ve created a feeding bonanza for turkeys.
Wild Turkeys feeding on grasshoppers along a forest road.
Wild Turkeys feeding on an abundance of grasshoppers along a forest road.
An American Kestrel feeds on a grasshopper while ignoring the abundance of Spotted Lanternflies swarming the adjacent utility pole.  In Susquehanna valley farmlands, grasshopper and kestrel numbers are down.  Lanternflies, on the other hand, have got it made.
Early Successional Growth
Maintaining areas bordering roads, forests, wetlands, farmlands, and human development in a state of early succession can provide and ideal mix of mature grasses and broadleaf plants for grasshoppers, pollinators, birds, and other wildlife.

Photo of the Day

Annual Wildflowers Along Corn Field.
Spectacular annual wildflowers in bloom along a border separating a fitness trail from a field of maize in Hershey, Pennsylvania.  Such plantings can provide vital habitat for pollinators that otherwise find no sustenance among monocultures of neonicotinoid-treated crops like corn and soybeans.

Monarch an Endangered Species: What You Can Do Right Now

This month, the International Union for Conservation of Nature (I.U.C.N.) added the Migratory Monarch Butterfly (Danaus plexippus plexippus) to its “Red List of Threatened Species”, classifying it as endangered.  Perhaps there is no better time than the present to have a look at the virtues of replacing areas of mowed and manicured grass with a wildflower garden or meadow that provides essential breeding and feeding habitat for Monarchs and hundreds of other species of animals.

Monarch on Common Milkweed Flower Cluster
A recently arrived Monarch visits a cluster of fragrant Common Milkweed flowers in the garden at the susquehannawildlife.net headquarters.  Milkweeds included among a wide variety of plants in a garden or meadow habitat can help local populations of Monarchs increase their numbers before the autumn flights to wintering grounds commence in the fall.  Female Monarchs lay their eggs on milkweed leaves, then, after hatching, the larvae (caterpillars) feed on them before pupating.

If you’re not quite sure about finally breaking the ties that bind you to the cult of lawn manicuring, then compare the attributes of a parcel maintained as mowed grass with those of a space planted as a wildflower garden or meadow.  In our example we’ve mixed native warm season grasses with the wildflowers and thrown in a couple of Eastern Red Cedars to create a more authentic early successional habitat.

Comparison of Mowed Grass to Wildflower Meadow
* Particularly when native warm-season grasses are included (root depth 6′-8′)

Still not ready to take the leap.  Think about this: once established, the wildflower planting can be maintained without the use of herbicides or insecticides.  There’ll be no pesticide residues leaching into the soil or running off during downpours.  Yes friends, it doesn’t matter whether you’re using a private well or a community system, a wildflower meadow is an asset to your water supply.  Not only is it free of man-made chemicals, but it also provides stormwater retention to recharge the aquifer by holding precipitation on site and guiding it into the ground.  Mowed grass on the other hand, particularly when situated on steep slopes or when the ground is frozen or dry, does little to stop or slow the sheet runoff that floods and pollutes streams during heavy rains.

What if I told you that for less than fifty bucks, you could start a wildflower garden covering 1,000 square feet of space?  That’s a nice plot 25′ x 40′ or a strip 10′ wide and 100′ long along a driveway, field margin, roadside, property line, swale, or stream.  All you need to do is cast seed evenly across bare soil in a sunny location and you’ll soon have a spectacular wildflower garden.  Here at the susquehannawildllife.net headquarters we don’t have that much space, so we just cast the seed along the margins of the driveway and around established trees and shrubs.  Look what we get for pennies a plant…

Wildflower Garden
Some of the wildflowers and warm-season grasses grown from scattered seed in the susquehannawildlife.net headquarters garden.

Here’s a closer look…

Lance-leaved Coreopsis
Lance-leaved Coreopsis (Coreopsis lanceolata), a perennial.
Black-eyed Susan
Black-eyed Susan, a biennial or short-lived perennial.
Black-eyed Susan "Gloriosa Daisy"
“Gloriosa Daisy”, a variety of Black-eyed Susan, a biennial or short-lived perennial.
Purple Coneflower
Purple Coneflower, an excellent perennial for pollinators.  The ripe seeds provide food for American Goldfinches.
Common Sunflower
A short variety of Common Sunflower, an annual and a source of free bird seed.
Common Sunflower
Another short variety of Common Sunflower, an annual.

All this and best of all, we never need to mow.

Around the garden, we’ve used a northeast wildflower mix from American Meadows.  It’s a blend of annuals and perennials that’s easy to grow.  On their website, you’ll find seeds for individual species as well as mixes and instructions for planting and maintaining your wildflower garden.  They even have a mix specifically formulated for hummingbirds and butterflies.

Annuals in bloom
When planted in spring and early summer, annuals included in a wildflower mix will provide vibrant color during the first year.  Many varieties will self-seed to supplement the display provided by biennials and perennials in subsequent years.
Wildflower Seed Mix
A northeast wildflower mix from American Meadows.  There are no fillers.  One pound of pure live seed easily plants 1,000 square feet.

Nothing does more to promote the spread and abundance of non-native plants, including invasive species, than repetitive mowing.  One of the big advantages of planting a wildflower garden or meadow is the opportunity to promote the growth of a community of diverse native plants on your property.  A single mowing is done only during the dormant season to reseed annuals and to maintain the meadow in an early successional stage—preventing reversion to forest.

For wildflower mixes containing native species, including ecotypes from locations in and near the Lower Susquehanna River Watershed, nobody beats Ernst Conservation Seeds of Meadville, Pennsylvania.  Their selection of grass and wildflower seed mixes could keep you planting new projects for a lifetime.  They craft blends for specific regions, states, physiographic provinces, habitats, soils, and uses.  Check out these examples of some of the scores of mixes offered at Ernst Conservation Seeds

      • Pipeline Mixes
      • Pasture, Grazing, and Hay Mixes
      • Cover Crops
      • Pondside Mixes
      • Warm-season Grass Mixes
      • Retention Basin Mixes
      • Wildlife Mixes
      • Pollinator Mixes
      • Wetland Mixes
      • Floodplain and Riparian Buffer Mixes
      • Rain Garden Mixes
      • Steep Slope Mixes
      • Solar Farm Mixes
      • Strip Mine Reclamation Mixes

We’ve used their “Showy Northeast Native Wildflower and Grass Mix” on streambank renewal projects with great success.  For Monarchs, we really recommend the “Butterfly and Hummingbird Garden Mix”.  It includes many of the species pictured above plus “Fort Indiantown Gap” Little Bluestem, a warm-season grass native to Lebanon County, Pennsylvania, and milkweeds (Asclepias), which are not included in their northeast native wildflower blends.  More than a dozen of the flowers and grasses currently included in this mix are derived from Pennsylvania ecotypes, so you can expect them to thrive in the Lower Susquehanna River Watershed.

Swamp Milkweed
Swamp Milkweed, a perennial species, is included in the Ernst Seed “Butterfly and Hummingbird Garden Mix”.  It is a favorite of female Monarchs seeking a location to deposit eggs.
Monarch Caterpillar feeding on Swamp Milkweed
A Monarch larva (caterpillar) feeding on Swamp Milkweed.
Butterfly Weed
Butterfly Weed (Asclepias tuberosa) is included in the Ernst Seed “Butterfly and Hummingbird Garden Mix”.  This perennial is also known as Butterfly Milkweed.
Tiger Swallowtails visiting Butterfly Weed
Eastern Tiger Swallowtails are among the dozens of species of pollinators that will visit Butterfly Weed.

In addition to the milkweeds, you’ll find these attractive plants included in Ernst Conservation Seed’s “Butterfly and Hummingbird Garden Mix”, as well as in some of their other blends.

Wild Bergamot
The perennial Wild Bergamot, also known as Bee Balm, is an excellent pollinator plant, and the tubular flowers are a favorite of hummingbirds.
Oxeye
Oxeye is adorned with showy clusters of sunflower-like blooms in mid-summer.  It is a perennial plant.
Plains Coreopsis
Plains Coreopsis (Coreopsis tinctoria), also known as Plains Tickseed, is a versatile annual that can survive occasional flooding as well as drought.
Gray-headed Coneflower
Gray-headed Coneflower (Ratibida pinnata), a tall perennial, is spectacular during its long flowering season.
Monarch on goldenrod.
Goldenrods are a favorite nectar plant for migrating Monarchs in autumn.  They seldom need to be sown into a wildflower garden; the seeds of local species usually arrive on the wind.  They are included in the “Butterfly and Hummingbird Garden Mix” from Ernst Conservation Seeds in low dose, just in case the wind doesn’t bring anything your way.
Partridge Pea
Is something missing from your seed mix?  You can purchase individual species from the selections available at American Meadows and Ernst Conservation Seeds.  Partridge Pea is a good native annual to add.  It is a host plant for the Cloudless Sulphur butterfly and hummingbirds will often visit the flowers.  It does really well in sandy soils.
Indiangrass in flower.
Indiangrass is a warm-season species that makes a great addition to any wildflower meadow mix.  Its deep roots make it resistant to drought and ideal for preventing erosion.

Why not give the Monarchs and other wildlife living around you a little help?  Plant a wildflower garden or meadow.  It’s so easy, a child can do it.

Planting a riparian buffer with wildflowers and warm-season grasses
Volunteers sow a riparian buffer on a recontoured stream bank using wildflower and warm-season grass seed blended uniformly with sand.  By casting the sand/seed mixture evenly over the planting site, participants can visually assure that seed has been distributed according to the space calculations.
Riparian Buffer of wildflowers
The same seeded site less than four months later.
Monarch Pupa
A Monarch pupa from which the adult butterfly will emerge.

The Layover

After nearly a full week of record-breaking cold, including two nights with a widespread freeze, warm weather has returned.  Today, for the first time this year, the temperature was above eighty degrees Fahrenheit throughout the lower Susquehanna region.  Not only can the growing season now resume, but the northward movement of Neotropical birds can again take flight—much to our delight.

A rainy day on Friday, May 8, preceded the arrival of a cold arctic air mass in the eastern United States.  It initiated a sustained layover for many migrating birds.

Bobolinks (Dolichonyx oryzivorus) in flocks of as many as fifty birds gathered in weedy meadows and alfalfa fields for the week.
A Bobolink sheltering in a field of Sweet Vernal Grass (Anthoxanthum odoratum) during the rain on Friday, May 8th.
Two of seven Solitary Sandpipers (Tringa solitaria) in a wet field on Friday, May 8.  Not-so-solitary after all.
Grounded by inclement weather, Rose-breasted Grosbeaks (Pheucticus ludovicianus) made visits to suburban bird feeders in the lower Susquehanna valley.  (Charles A. Fox image)

Freeze warnings were issued for five of the next six mornings.  The nocturnal flights of migrating birds, most of them consisting of Neotropical species by now, appeared to be impacted.  Even on clear moonlit nights, these birds wisely remained grounded.  Unlike the more hardy species that moved north during the preceding weeks, Neotropical birds rely heavily on insects as a food source.  For them, burning excessive energy by flying through cold air into areas that may be void of food upon arrival could be a death sentence.  So they wait.

A freeze warning was issued for Saturday morning, May 9, in the counties colored dark blue on the map.  (NOAA/National Weather Service image)
This radar image from 3:28 A.M. Saturday morning, May 9, indicates a minor movement of birds in the Great Plains, but there are no notable returns shown around weather radar sites in the freeze area, including the lower Susquehanna valley.  (NOAA/National Weather Service image)
To avoid the cold wind on Saturday, May 9, this Veery was staying low to the ground within a thicket of shrubs in the forest.
This Black-throated Blue Warbler avoided the treetops and spent time in the woodland understory.  He sang not a note.  With birds conserving energy for the cold night(s) ahead, it was uncharacteristically quiet for the second Saturday in May.
A secretive Northern Waterthrush (Parkesia noveboracensis) remained in a wetland thicket.
A Scarlet Tanager (Piranga olivacea) tucks his bill beneath a wing and fluffs-up to fight off the cold during a brief May 9th snow flurry.
In open country, gusty winds kept Eastern Kingbirds, a species of flycatcher, near the ground in search of the insects they need to sustain them.
Horned Larks are one of the few birds that attempt to scratch out an existence in cultivated fields.  The application of herbicides and the use of systemic insecticides (including neonicotinoids) eliminates nearly all weed seeds and insects in land subjected to high-intensity farming.  For most birds, including Neotropical migrants, cropland in the lower Susquehanna valley has become a dead zone.  Birds and other animals might visit, but they really don’t “live” there anymore.
Unable to find flying insects over upland fields during the cold snap, swallows concentrated over bodies of water to feed.  Some Tree Swallows may have abandoned their nests to survive this week’s cold.  Fragmentation of habitats in the lower Susquehanna valley reduces the abundance and diversity of natural food sources for wildlife.  For birds like swallows, events like late-season freezes, heat waves, or droughts can easily disrupt their limited food supply and cause brood failure.
For this Barn Swallow, attempting to hunt insects above the warm pavement of a roadway had fatal consequences.
Another freeze warning was issued for Sunday morning, May 10, in the counties colored dark blue on this map.  (NOAA/National Weather Service image)
This radar image from 4:58 A.M. Sunday morning, May 10, again indicates the absence of a flight of migrating birds in the area subjected to freezing temperatures.  Unlike migrants earlier in the season, the Neotropical species that move north during the May exodus appear unwilling to resume their trek during freezing weather.  (NOAA/National Weather Service image)
On Sunday evening, May 10, a liftoff of nocturnal migrants is indicated around radar sites along the Atlantic Coastal Plain and, to a lesser degree, in central Pennsylvania.  The approaching rain and yet another cold front quickly grounded this flight.
After a one day respite, yet another freeze warning was issued for Tuesday morning, May 12.  (NOAA/National Weather Service image)
And again, no flight in the freeze area.  (NOAA/National Weather Service image)
The freeze warning for Wednesday morning, May 13.  (NOAA/National Weather Service image)
And the nocturnal flight: heavy in the Mississippi valley and minimal in the freeze area.  (NOAA/National Weather Service image)
The freeze on Thursday morning, May 14.  (NOAA/National Weather Service image)
At 3:08 A.M. on May 14th, a flight is indicated streaming north through central Texas and dispersing into the eastern half of the United States, but not progressing into New England.  (NOAA/National Weather Service image)
The flight at eight minutes after midnight this morning.  Note the stormy cold front diving southeast across the upper Mississippi valley.  As is often the case, the concentration of migrating birds is densest in the warm air ahead of the front.  (NOAA/National Weather Service image)

Today throughout the lower Susquehanna region, bird songs again fill the air and it seems to be mid-May as we remember it.  The flights have resumed.

Indigo Bunting numbers are increasing as breeding populations arrive and migrants continue through.  Look for them in thickets along utility and railroad right-of-ways.
Common Yellowthroats and other colorful warblers are among the May migrants currently resuming their northward flights.
The echoes of the songs of tropical birds are beginning to fill the forests of the lower Susquehanna watershed.  The flute-like harmonies of the Wood Thrush are among the most impressive.
Ovenbirds are ground-nesting warblers with a surprisingly explosive song for their size.  Many arrived within the last two days to stake out a territory for breeding.  Listen for “teacher-teacher-teacher” emanating from a woodland near you.

How I Spent My Summer Vacation

It’s a hot summer weekend with a sun so bright that creosote is dripping from utility poles onto the sidewalks.  Dodging these sticky little puddles of tar can cause one to reminisce about sultry days-gone-by.

Sometime in July or August each year, about half a century ago, we would cram all the gear for seven days of living into the car and head for the beaches of Delmarva or New Jersey.  It was family vacation time, that one week a year when the working class fantasizes that they don’t have it so bad during the other fifty-one weeks of the year.

The trip to the coast from the Susquehanna valley was a day-long journey.  Back then, four-lane highways were few beyond the cities of the northeast corridor and traffic jams stretched for miles.  Cars frequently overheated and steam rolled from beneath the hoods of those stopped to cool down.  There were even 55-gallon drums of non-potable water positioned at known choke points along some of the state roads so that motorists could top off their radiators and proceed on.  Within these back-ups there were many Volkswagen Beetles pausing along the side of the road with the rear hood propped up.  Their air-cooled engines would overheat on a hot day if the car wasn’t kept moving.  But, despite the setbacks, all were motivated to continue.  In time, with perseverance, the smell of saltmarsh air was soon rolling in the windows.  Our destination was near.

At the shore, priority one was to spend plenty of time at the beach.  Sunbathers lathered up with various concoctions of oils and moisturizers, including my personal favorite, cocoa butter, then they broiled themselves in the raging rays of the fusion-reaction furnace located just eight light-minutes away.  Reflected from the white sand and ocean surf, the flaming orb’s blinding light did a thorough job of cooking all the thousands of oil-basted sun worshippers packing the tidal zone for miles and miles.  You could smell the hot cocoa butter in the summer air as they burned.  Well, maybe not, but you could smell something there.

By now, you’re probably saying, “Hey, why weren’t you idiots wearing protection from the sun’s harmful U.V. rays?”

Good question.  Uncle Tyler Dyer reminds me that back in the sixties, a sunscreen was a shade hung to cover a window.  He continued, “Man, the only sun block we had was a beach ball that happened to pass between us and the sun.”

A beach ball doesn’t cast much of a shadow.  (NASA Solar Dynamics Observatory base image)

During several of our summertime beach visits in the early 1970s, we got a different sort of oil treatment—tar balls.  We never noticed the things until we got out of the water.  Playing around at the tide line and taking a tumble in the surf from time to time, we must have picked them up when we rolled in the sand.

Uncle Ty wasn’t happy, “Man, they’re sticking all over our legs and feet, and look at your swim trunks, they’re ruined.  And look in the sand, they’re everywhere.”  The event was one of the seeds that would in time grow into Uncle Ty’s fundamental distrust of corporate culture.

Looking around, tar balls were all over everyone who happened to be near the water.  Rumor on the beach was that they came from ships that passed by offshore earlier in the day.  The probable source was the many oil spills that had occurred in the Mid-Atlantic region in those years.  During the first six months of 1973 alone, there were over 800 oil spills there.  Three hundred of those spills occurred in the waters surrounding New York City.  The largest, almost half a million gallons, occurred in New York Harbor when a cargo ship collided with the tanker “Esso Brussels”.  Forty percent of that spill burned in the fire that followed the mishap, the remainder entered the environment.

When it was time to clean up, we slowly removed the tar from our legs and feet by rubbing it away with a rag soaked in charcoal lighter fluid or gasoline.  Needless to say, our skin turned redder than it had already been from sunburn.

Letting swimmers and wildlife roll around in the sand is no longer the preferred method of cleaning up tar balls from man-made oil spills.  Here, President Obama examines tar balls resulting from the April 20, 2010, B.P. Deepwater Horizon spill in the Gulf of Mexico.  An organized cleanup effort followed this May 28, 2010, visit to the polluted Port Fourchon beach in Louisiana.

After a full day in the surf, we’d be on our way back to our “home base” for summer vacation, a campground nestled somewhere in the pines on the mainland side of the tidal marshes behind our beach’s barrier island.  There, we’d shake the sand out of our trunks and savor the feeling of dry clothing.  As the sun set, the smoke, flicker, and crackle of dozens of campfires filled the spaces between the tents and camping trailers.  Colored lights strung around awnings dazzled sun-weary eyes as night descended across the landscape.  We’d commence the process of incinerating some marshmallows soon after.  Then, sometime while we were roasting our weenies and warming our buns, we’d hear it.

His device didn’t have a very good muffler.  It sounded like a rusty old lawn mower running on the back of a rusty old truck that didn’t sound much better.  And you could see the cloud rising above the campsites around the corner as he approached.  It was the mosquito man, come to rid the place of pesky nocturnal biting insects.  Behind him, always, were young boys on bicycles riding in and out of the fog of insecticide that rolled from the back of the truck.

Curious children seen following the mosquito man in a 1947 Universal Newsreel.

One was wise to quickly eat your campfire food and put the rest away before the fog rolled in.  You had just minutes to choke down that burned up hot dog.  Then the sense of urgency was gone.  Everyone just sat around at picnic tables and on lawn chairs bathing in the airborne cloud.  A thin layer of insecticide rubbed into the skin along with the liberal doses of Noxzema being applied to soothe sunburn pain will get you through the night just fine.

By the early 1970s, fogging of campgrounds to eliminate nuisance mosquitos was conducted using primarily the insecticide carbaryl (Sevin).  Prior to that, in the years following World War II, DDT was the one-trick pony for killing everything everywhere.  In 1947, the youth of San Antonio, Texas were subjected to repetitive direct spraying with DDT to eliminate the “germs” responsible for poliomyelitis.  It was a misguided use of the pesticide.  (Universal Newsreel image)
Don’t you kids know that there’s sodium nitrite and saturated fat in those luncheon meats you’re eating?  And the bread, aren’t you concerned about all that gluten?  Oh, and by the way, they’re spraying you down with DDT again.  It really happened in 1947 in San Antonio, Texas.  (Universal Newsreel image)

Perhaps the most memorable event to occur during our summer vacations happened at the moment of this writing, fifty years ago.

We were vacationing in a campground in southern New Jersey.  Our family and the family of my dad’s co-worker gathered in a mosquito-mesh tent surrounding a small black-and-white television.  An extension cord was strung to a receptacle on a nearby post, and the cathode ray tube produced the familiar picture of glowing blue tones to illuminate the otherwise dark scene.  There was constant experimentation with the whip antenna to try to get a visible signal.  There were no local UHF broadcasters and the closest VHF television stations were in Philadelphia, so the picture constantly had “snow” diminishing its already poor clarity.  But we could see it, and I’ll never forget it.

Neil Armstrong steps off the landing gear pad to be the first human to walk on the moon.  July 20, 1969, 10:56 P.M. E.D.T.  (NASA image)
Armstrong left the field of view of the LEM-mounted camera for minutes at a time as he completed various tasks.  TV viewers heard audio of his conversations with partner Edwin “Buzz” Aldrin and Houston Mission Control during these interludes.  It was definitely not coverage designed for the short attention span of typical TV audiences.  (NASA image)
Edwin “Buzz” Aldrin descends the ladder on the LEM’s landing gear to reach the moon’s surface 19 minutes after Armstrong.  (NASA image)
Because NASA used a different video format than broadcast television, images seen at the time of the moon walk were of poor quality, produced by aiming a TV camera at a NASA monitor.  Quality still images, including this one of Edwin “Buzz” Aldrin descending to the lunar surface, were available only after the astronauts returned exposed film to earth for processing.  (NASA image by Neil Armstrong)
Edwin “Buzz” Aldrin overlooking the LEM “Eagle” at Tranquility Base.  (NASA image by Neil Armstrong)
Neil Armstrong took this iconic image of Edwin “Buzz” Aldrin using a Hasselblad camera.  His reflection can be seen in Aldrin’s visor.  (NASA image by Neil Armstrong)
Neil Armstrong (1930-2012), first man on the moon.  (NASA image)

 

  SOURCES

Andelman, David A.  “Oil Spills Here Total 300 in ’73”.  The New York Times.  August 8, 1973.  p.41.

Cortright, Edgar M. (Editor).  1975.  Apollo Expeditions to the Moon.  National Aeronautics and Space Administration.  Washington, DC.

 

 

Noxious Benefactor

It’s sprayed with herbicides.  It’s mowed and mangled.  It’s ground to shreds with noisy weed-trimmers.  It’s scorned and maligned.  It’s been targeted for elimination by some governments because it’s undesirable and “noxious”.  And it has that four letter word in its name which dooms the fate of any plant that possesses it.   It’s the Common Milkweed, and it’s the center of activity in our garden at this time of year.  Yep, we said milk-WEED.

Now, you need to understand that our garden is small—less than 2,500 square feet.  There is no lawn, and there will be no lawn.  We’ll have nothing to do with the lawn nonsense.  Those of you who know us, know that the lawn, or anything that looks like lawn, are through.

Anyway, most of the plants in the garden are native species.  There are trees, numerous shrubs, some water features with aquatic plants, and filling the sunny margins is a mix of native grassland plants including Common Milkweed.  The unusually wet growing season in 2018 has been very kind to these plants.  They are still very green and lush.  And the animals that rely on them are having a banner year.  Have a look…

The flowers of the Common Milkweed were exceptionally fragrant this year.  At their peak in early June, their hyacinth-or lilac-like aroma was so prevalent, it drifted into our building and overwhelmed the stink of the neighbor’s filthy dumpster that he had placed 12 feet away from our walls (100 feet from his).
Common Milkweed attracts a pollinating Greenbottle Fly (Lucilia species).  The dumpster attracts the invasive House Fly (Musca domestica), carrier of dysentery, typhoid, and other wonderful diseases.  Are you following this?  Remember as we proceed, milkweed is “noxious”.
Busy Eastern Carpenter Bees (Xylocopa virginica) load up with pollen from the flowers of the Common Milkweed.
A Red Milkweed Beetle (Tetraopes tetrophthalmus) munches on a tender fresh Common Milkweed leaf in mid-June.
Following the pollination of the flowers, seed pods will begin to grow.  We trim these off the plants.  The removal of the extra weight allows most of the stems to remain erect through stormy weather.  You’ll still get new plants from underground runners.  As you may have guessed, we’re trying to keep these plants upright and strong to host Monarch butterfly larvae.

We’ve planted a variety of native grassland species to help support the milkweed structurally and to provide a more complete habitat for Monarch butterflies and other native insects.  This year, these plants are exceptionally colorful for late-August due to the abundance of rain.  The warm season grasses shown below are the four primary species found in the American tall-grass prairies and elsewhere.

Big Bluestem, a native warm-season grass in flower.
Little Bluestem (Schizachyrium scoparium “Fort Indiantown Gap”) in flower.  This variety grows on the tank range at the military base where the armored vehicles and prescribed burns substitute for the  herd animals and fires of the prairie to prevent succession and allow it to thrive.
Partridge Pea can tolerate sandy soil and is a host plant for vagrant Cloudless Sulphur butterflies.
Black-eyed Susan (Rudbeckia hirta) is a popular native grassland wildflower.
Indiangrass (Sorghastrum nutans) in flower.  This and the other native plants shown here are available as seed from Ernst Seed Company in Meadville (PA).  They have an unbelievably large selection of indigenous species.  You can plant a small plot or acres and acres using really good mixes blended for purposes ranging from reclaiming pipeline right-of-ways and strip mines to naturalizing backyard gardens.
A Red Admiral (Vanessa atalanta) butterfly, a migratory species like the Monarch, on Purple Coneflower (Echinacea purpurea).  Yes, it is that Echinacea, the same one used as a supplement and home remedy.

There was Monarch activity in the garden today like we’ve never seen before—and it revolved around milkweed and the companion plants.

A female Monarch laying eggs on a Common Milkweed leaf.
A third instar Monarch caterpillar with Oleander Aphids (Aphis nerii) on a Common Milkweed leaf.  Both of these insect species absorb toxins from the milkweed which makes them distasteful to predators.
Fifth instar (left and center) and fourth instar (right) monarch caterpillars devour a Common Milkweed leaf.  There were over thirty of these caterpillars in just a ten by ten feet area this morning.  We hope that if you’re keeping a habitat for Monarchs, you’re enjoying the same fortune right now!
A slow-moving Monarch stopped for a break after making the circuit to deposit eggs on milkweed throughout the garden.
Third instar (top), fourth instar (right), and fifth instar (left) Monarch caterpillars quickly consume the leaf of a Common Milkweed plant.  Caterpillars emerging from eggs deposited today may not have sufficient late-season food to complete the larval segment of their life cycle.  Need more milkweed!
After benefiting from the nourishment of the Common Milkweed plant, a fifth instar Monarch caterpillar begins pupation on Big Bluestem grass.
Two hours later, the chrysalis is complete.
Another chrysalis, this one on flowering Switchgrass just two feet away from the previous one.  An adult Monarch will emerge from this pupa to become part of what we hope will be the most populated southbound exodus for the species in over five years.
There it is, soon ready to fly away.  And all courtesy of the noxious milkweed.
A chrysalis can often be found on man-made objects too.  This one is on the rim of a flower pot.
Ornamental flowers can attract adult Monarch butterflies seeking nectar.  We’re now more careful to select seeds and plants that have not been treated with neonicotinoid insecticides.  There’s growing concern over the impact these compounds may be having on pollinating species of animals.  Oh…and we don’t mow, whack, cut, mutilate, or spray herbicides on our milkweed, but you probably figured that out already.

 SOURCES

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

Fussy Eaters

She ate only toaster pastries…that’s it…nothing else.  Every now and then, on special occasions, when a big dinner was served, she’d have a small helping of mashed potatoes, no gravy, just plain, thank you.  She received all her nutrition from several meals a week of macaroni and cheese assembled from processed ingredients found in a cardboard box.  It contains eight essential vitamins and minerals, don’t you know?  You remember her, don’t you?

Adult female butterflies must lay their eggs where the hatched larvae will promptly find the precise food needed to fuel their growth.  These caterpillars are fussy eaters, with some able to feed upon only one particular species or genus of plant to grow through the five stages, the instars, of larval life.  The energy for their fifth molt into a pupa, known as a chrysalis, and metamorphosis into an adult butterfly requires mass consumption of the required plant matter.  Their life cycle causes most butterflies to be very habitat specific.  These splendid insects may visit the urban or suburban garden as adults to feed on nectar plants, however, successful reproduction relies upon environs which include suitable, thriving, pesticide-free host plants for the caterpillars.  Their survival depends upon more than the vegetation surrounding the typical lawn will provide.

The Monarch (Danaus plexippus), a butterfly familiar in North America for its conspicuous autumn migrations to forests in Mexico, uses the milkweeds (Asclepias) almost exclusively as a host plant.  Here at  Conewago Falls, wetlands with Swamp Milkweed (Asclepias incarnata) and unsprayed clearings with Common Milkweed (A. syriaca) are essential to the successful reproduction of the species.  Human disturbance, including liberal use of herbicides, and invasive plant species can diminish the biomass of the Monarch’s favored nourishment, thus reducing significantly the abundance of the migratory late-season generation.

Monarch caterpillar after a fourth molt.  The fifth instar feeding on Swamp Milkweed.
A fifth molt begets the Monarch pupa, the chrysalis, from which the showy adult butterfly will emerge.
Adult Monarch feeding on Goldenrod (Solidago) nectar.

Butterflies are good indicators of the ecological health of a given environment.  A diversity of butterfly species in a given area requires a wide array of mostly indigenous plants to provide food for reproduction.  Let’s have a look at some of the species seen around Conewago Falls this week…

An adult Silvery Checkerspot (Chlosyne nycteis) visiting a nectar plant, Partridge Pea (Chamaecrista fasciculata).  Wingstem (Verbesina alternifolia), a plant of the Riparian Woodlands, is among the probable hosts for the caterpillars.
A Gray Hairstreak (Strymon melinus) visits Crown Vetch, a possible host plant.  Other potential larval food in the area includes Partridge Pea, Halberd-leaved Rose Mallow (Hibiscus laevis) of the river shoreline, and Swamp Rose Mallow (Hibiscus moscheutos), a plant of wetlands.
The Eastern Tailed Blue (Cupido comyntas) may use Partridge Pea , a native wildflower species, and the introduced Crown Vetch (Securigera/Coronilla varia) as host and nectar plants at Conewago Falls.
The Least Skipper (Ancyloxypha numitor) is at home among tall grasses in woodland openings, at riverside, and in the scoured grassland habitat of the Pothole Rocks in the falls.  Host plants available include Switchgrass (Panicum vigatum), Freshwater Cordgrass (Spartina pectinata), and Foxtails (Setaria).
The Zabulon Skipper (Poanes zabulon) is an inhabitant of moist clearings where the caterpillars may feed upon Lovegrasses (Eragrostis) and Purpletop (Tridens flavus).
The Eastern Tiger Swallowtail (Papilio glaucus), a female seen here gathering nectar from Joe-Pye Weed (Eutrochium), relies upon several forest trees as hosts. Black Cherry (Prunus serotina), Willow (Salix), Yellow Poplar (Liriodendron tulipifera), also known as Tuliptree, and Green Ash (Fraxinus pennsylvanica) are among the local species known to be used.  The future of the latter food species at Conewago Falls is doubtful.  Fortunately for the Eastern Tiger Swallowtail, the “generalist” feeding requirements of this butterfly’s larvae enable the species to survive the loss of a host plant.
A female Eastern Tiger Swallowtail, black morph, gathering nectar from Joe-Pye Weed.
The Zebra Swallowtail (Protographium marcellus), an adult seen here on Joe-Pye Weed, feeds exclusively upon Pawpaw (Asimina) trees as a caterpillar.  This butterfly species may wander, but its breeding range is limited to the moist Riparian Woodlands where colonial groves of Pawpaw may be found.  The Common Pawpaw (Asimina triloba), our native species in Pennsylvania, and the Zebra Swallowtail occur at the northern edge of their geographic ranges in the Lower Susquehanna River Watershed.  Planting Pawpaw trees as an element of streamside reforestation projects certainly benefits this marvelous butterfly.

The spectacularly colorful butterflies are a real treat on a hot summer day.  Their affinity for showy plants doubles the pleasure.

By the way, I’m certain by now you’ve recalled that fussy eater…and how beautiful she grew up to be.

SOURCES

Brock, Jim P., and Kaufman, Kenn.  2003.  Butterflies of North America.  Houghton Mifflin Company.  New York, NY.

The Antagonist

They can be a pesky nuisance.  The annoying high-frequency buzzing is bad enough, but it’s the quiet ones that get you.  While you were swatting at the noisy one, the silent gender sticks you and begins to feed.  Maybe you know it, or maybe you don’t.   She could make you itch and scratch.  If she’s carrying a blood-borne pathogen, you could get sick and possibly die.

To humans, mosquitos are the most dangerous animal in the world (though not in the United States where man himself and the domestic dog are more of a threat).  Globally, the Anopheles mosquitos that spread Malaria have been responsible for millions and millions of human deaths.  Some areas of Africa are void of human habitation due to the prevalence of Malaria-spreading Anopheles mosquitos.  In the northeastern United States, the Northern House Mosquito (Culex pipiens), as the carrier of West Nile Virus, is the species of greatest concern.  Around human habitations, standing water in tires, gutters, and debris are favorite breeding areas.  Dumping stagnant water helps prevent the rapid reproduction of this mosquito.

In recent years, the global distribution of these mosquito-borne illnesses has been one of man’s inadvertent accomplishments.  An infected human is the source of pathogens which the feeding mosquito transmits to another unsuspecting victim.  Infectious humans, traveling the globe, have spread some of these diseases to new areas or reintroduced them to sectors of the world where they were thought to have been eliminated.  Additionally, where the specific mosquito carrier of a disease is absent, the mobility of man and his cargos has found a way to transport them there.  Aedes aegypti, the “Yellow Fever Mosquito”, carrier of its namesake and the Zeka Virus, has found passage to much of the world including the southern United States.  Unlike other species, Aedes aegypti dwells inside human habitationsthus transmitting disease rapidly from person to person.  Another non-native species, the Asian Tiger Mosquito (Aedes albopictus), vector of Dengue Fever in the tropics, arrived in Houston in 1985 in shipments of used tires from Japan and in Los Angeles in 2001 in wet containers of “lucky bamboo” from Taiwan…some luck.

Asian Tiger Mosquito in action during the daylight hours, typical behavior of the genus. This species has been found in the area of Conewago Falls since at least 2013.

Poor mosquito, despite the death, suffering, and misery it has brought to Homo sapiens and other species around the planet, it will never be the most destructive animal on earth.  You, my bloodthirsty friends, will place second at best.  You see, mosquitos get no respect, even if they do create great wildlife sanctuaries by scaring people away.

The winner knows how to wipe out other species and environs not only to ensure its own survival, but, in many of its populations, to provide leisure, luxury, gluttony, and amusement.  This species possesses the cognitive ability to think and reason.  It can contemplate its own existence and the concepts of time.  It is aware of its history, the present, and its future, though its optimism about the latter may be its greatest delusion.  Despite possessing intellect and a capacity to empathize, it is devious, sinister, and selfish in its treatment of nearly every other living thing around it.  Its numbers expand and its consumption increases.  It travels the world carrying pest and disease to all its corners.  It pollutes the water, land, and air.  It has developed language, culture, and social hierarchies which create myths and superstitions to subdue the free will of its masses.   Ignoring the gift of insight to evaluate the future, it continues to reproduce without regard for a means of sustenance.  It is the ultimate organism, however, its numbers will overwhelm its resources.  The crowning distinction will be the extinction.

Homo sapiens will be the first animal to cause a mass extinction of life on earth.  The forces of nature and the cosmos need to wait their turn; man will take care of the species annihilation this time around.  The plants, animals, and clean environment necessary for a prosperous healthy life will cease to exist.  In the end, humans will degenerate, live in anguish, and leave no progeny.  Fate will do to man what he has done to his co-inhabitants of the planet.

The Bald Eagle (Haliaeetus leucocephalus) is again a breeding species in the Susquehanna River watershed.  It is generally believed that during the mid-twentieth century, Dichlorodiphenyltrichloroethane (DDT) pesticide residues accumulated in female top-of-the-food-chain birds including Bald Eagles.  As a result, thinner egg shells were produced.  These shells usually cracked during incubation, leading to failed reproduction in entire populations of birds, particularly those that fed upon fish or waterfowl.  In much of the developed world, DDT was used liberally during the mid-twentieth century to combat Malaria by killing mosquitos.  It was widely used throughout the United States as a general insecticide until it was banned here in 1972.  (Editors Note:  There is the possibility that polychlorinated biphenyls [P.C.B.s] and other industrial pollutants contributed to the reproductive failure of birds at the apex of aquatic food chains.  Just prior to the recovery of these troubled species, passage of the Clean Water Act in 1972 initiated reductions in toxic discharges from point sources into streams, rivers, lakes, bays, and oceans.  Production of P.C.B.s was banned in the United States in 1978.  Today, P.C.B.s from former discharge and dumping sites continue to be found in water.  Spills can still occur from sources including old electric transformers.)
To substitute any other beast would be folly.  Man, the human, Homo sapiens, the winner and champion, will repeatedly avail himself as the antagonist during our examination of the wonders of wildlife.  He is the villain.  The tragedy of his self-proclaimed dominion over the living things of the world will wash across these pages like muddy water topping a dam.  There’s nothing I can do about it, aside from fabricating a bad novel with a fictional characterization of man.  So let’s get on with it and take a look at “A Natural History of Conewago Falls”.  Let’s discover the protagonist, the heroic underdog of our story, “Life in the Lower Susquehanna River Watershed.”

Over the top today.
SOURCES

Avery, Dennis T.  1995.  Saving the Planet with Pesticides and Plastic: The Environmental Triumph of High-Yield Farming.  Hudson Institute.  Indianapolis, Indiana.

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

Newman, L.H.  1965.  Man and Insects.  The Natural History Press.  Garden City, New York.