Photo of the Day

Great Spangled Fritillary
Along a quiet forest road, a Great Spangled Fritillary visits Red Clover (Trifolium pratense) to feed on nectar.

Photo of the Day

Common Carp
We came across this photo from a dive we did back in 1999 and thought it timely.  Here a large non-native Common Carp churns up a cloud of nutrient-charged sediment as it roots its way through a bed of American Eelgrass and Water Stargrass in the Susquehanna below Conewago Falls.  (Vintage 35 mm image)

Common Carp: A Menace Meant for the Dinner Plate

One of the earliest non-native fish species to be widely released into North American waterways was the Common Carp.  Stocks brought to the United States were likely sourced from populations already naturalized throughout much of western Europe after introductions originating from the fish’s native range in Eurasia, probably including the Danube and other watersheds east through the Volga.  In western Europe, the species promised to be an abundant and easily cultivated food source.  Under the same premise, carp were transported to the United States during the early 1800s and widely introduced into streams, lakes, and rivers throughout the country.

Common Carp thrive in nutrient-rich waters, particularly those subjected to sewage discharge and agricultural runoff, conditions which were already prevalent during the Common Carp’s initial introduction and have remained widespread ever since.  Within these polluted streams, lakes, and ponds, introduced carp feed aggressively on benthic organisms and plants, stirring up decaying organic matter (mulm) from the substrate.  This process raises turbidity in the water column and releases excessive amounts of the nutrient phosphorus resulting in unusually large algal blooms.  Algal blooms can block sunlight from the longer-lived oxygen-producing vascular plants that grow in submerged environs.  Growing beneath a dense cloud or blanket of algae can compromise the vigor of oxygen-producing vascular plants and disable their biochemical functions within the aquatic ecosystem.  As the short-lived algae die, the bacteria that decay them begin to place increased oxygen demands on the water.  With less oxygen being produced by both the vascular plants and the algae, and with oxygen consumption increased by the activity of decomposers, conditions can become fatal for fish and other organisms.  This process is known as eutrophication.  Because Common Carp are among the species most tolerant of eutrophic conditions, they tend to thrive in the conditions they create while the native fishes perish.

Common Carp spawn in the spring, usually from late April through June, when the water temperature is as low as 58 degrees and as high as 83 degrees Fahrenheit.  This activity is often triggered by a rapid increase in water temperature.  In a small lake, this may be brought on by a string of sunny days in late April or May.  On larger streams and rivers, the temperature spike that initiates the spawn may not occur until warm rains and runoff enter the stream during June.

Common Carp
Seeing the exposed backs of Common Carp as they stir up mulm and other sediments while feeding along the edges of a body of water is not at all unusual.
Common Carp
But carp pursuing other carp into the shallows is a sign that spawning has commenced.
Common Carp Spawning
In water that is often less than a foot in depth, male carp follow the breeding females into egg-laying areas among debris and emergent vegetation.
Common Carp Spawning
A fountain of splashes can ensue as males try to outdo one another for a chance to fertilize the female’s eggs.
Common Carp Spawning
The males’ aggressive pursuit can even forced a large female to temporarily ground herself on the beach.

Common Carp are one of the most widely farmed and eaten fish in all the world.  Here in the United States, they were introduced beginning two hundred years ago because they were favorable to the palate, grew to large size quickly, and were a source of much needed food.  Today, the Common Carp is seldom found on the American dinner plate.  Yet, pound for pound, it is one of the most abundant fish in many of our waters, particularly in man-made lakes.  Like some of our other most invasive species—including Blue Catfish, Flathead Catfish, and Northern Snakehead—Common Carp are perhaps the most edible of our freshwater fishes.  For many cultures, they are an important staple.  For others, they are a delicacy or holiday treat.  In America, they do horrendous damage to aquatic ecosystems following establishment as a food crop that almost never gets harvested.  Did you realize that on the internet, there are literally hundreds of recipes and culinary videos available to show you how to prepare delicious dishes made with Common Carp?  It’s true.  And for the cost of a fishing license, you can catch all you want, usually several pounds at a time.  So why not give the marine fisheries a break?  Take the big leap and learn to eat invasive freshwater species instead.

Common Carp Breaching
Jumpin’ gefilte fish, it’s what’s for dinner!

Soakin’ Up the Smoky Sun

With temperatures finally climbing to seasonable levels and with stormy sun filtering through the yellow-brown smoke coming our way courtesy of wildfires in Alberta and other parts of central Canada, we ventured out to see what might be basking in our local star’s refracted rays…

Black Saddlebags
Dragonflies including this Black Saddlebags are now actively patrolling the edges of waterways and wetlands for prey and mates.
Common Green Darners
Here we see a pair of Common Green Darners flying in tandem…
Common Green Darners
…and, having already mated, stopping at a suitable location for the female to oviposit the fertilized eggs onto submerged plant stems.
Painted Turtles
A sunny day almost always brings out the reptiles, including these Painted Turtles…
Red-eared Slider
and the invasive Red-eared Slider, a native transplant from the American midwest.
Snapping Turtle
A really big Snapping Turtle will prey on almost anything, including other Snapping Turtles…
Golden Shiners
…but this one seems to be fascinated by something a lot smaller.  Something like these juvenile Golden Shiners seen here schooling in the sun-drenched shallows.
Northern Water Snakes
Turtles aren’t the only reptiles thriving in the heat.  Northern Water Snakes (Nerodia sipedon sipedon) take full advantage of a sun-drenched rock to warm up after spending time in the chilly water of a stream.
Northern Water Snakes
You know, no one loves a snake like another snake…
Northern Water Snakes
…and when it comes to these two snakes, it looks like love is in the air!
Spicebush Swallowtail
Butterflies like this Spicebush Swallowtail enjoy time in the sun, even while seeking out minerals in a patch of moist soil.
Woodchucks
After its siblings darted into the familial burrow upon our approach, this juvenile Woodchuck instead sought the attention of its nurturing mother.  Unlike its brothers and sisters, perhaps this little groundhog isn’t afraid of its own shadow.  Or does the smoky haze have the youngster all confused about what does and doesn’t constitute as a shadow?  Well, we can’t help you there, but you have a whole eight months to figure it out!

Brood XIV Periodical Cicada Emergence

Its been four years to the day since we posted our account of the big Brood X Periodical Cicada flight of 2021 in the Lower Susquehanna River Watershed.  With the Brood XIV clan of 17-year Periodical Cicadas getting ready fill the June air with their choruses in scattered parts of Pennsylvania’s Berks, Centre, Clinton, Franklin, Huntingdon, Juniata, Lancaster, Mifflin, Perry, Schuylkill, Snyder, Union, and York Counties right now, we thought it an appropriate time to open a new “Cicada” page here on the website.  Included is a list of both the annually and periodically emerging species found in the lower Susquehanna valley, as well as a copy of the article and ID photos from the 2021 occurrence of Brood X.  In coming months, we’ll be adding photos and maybe some sound clips of the different annual cicadas as well, so remember to check back from time to time for more content.

Periodical Cicada Nymph
Note the wings and red eyes of this periodical cicada nymph.  Within weeks it will join billions of others in a brief adult emergence to fly, mate, and then die.

In the short term, we’re going to pay a visit to the Brood XIV territory and will bring you updates as we get them.  Until then, be sure to click the new “Cicadas” tab at the top of this page to brush up on your ID of the three species of 17-year Periodical Cicadas.

Adult Periodical Cicada
Not to worry.  Cicadas are native, harmless, docile creatures when handled and they pose no threat to the long-term health of your healthy, well-established trees and other vegetation, so enjoy them while they’re here!

Photographs in Living Color: Black and White is Beautiful

Here at susquehannawildlife.net headquarters, we really enjoy looking back in time at old black-and-white pictures.  We even have an old black-and-white television that still operates quite well.  But on a nice late-spring day, there’s no sense sitting around looking at that stuff when we could be outside tracking down some sightings of a few wonderful animals.

American Toad Tadpoles
American Toad tadpoles have hatched from clusters of eggs deposited in this wet roadside ditch furnished with a clean supply of runoff filtered through a wide shoulder of early successional growth.  Recent rains have kept their vernal nursery flooded, giving them the time they need to quickly mature into tiny toads and hop away before scorching summer heat dries up their natal home.
Water Striders mating.
Weekend rains and creek flooding haven’t stopped these Water Striders from pairing up to begin their breeding cycle.
Common Whitetail
Around streams, lakes, ponds, and wetlands, the Common Whitetail is one of our most conspicuous dragonflies.
Great Blue Heron
Now that’s what we call a big beautiful bill, on a Great Blue Heron stalking fish.
Golden-backed Snipe Flies
These mating Golden-backed Snipe Flies (Chrysopilus thoracicus) are predatory insects, as are their larvae.  They are most frequently found in bottomland woods.
Eastern Ratsnake
About three feet in length, this Eastern Ratsnake is unusual because it still shows conspicuous remnants of the diamond-patterned markings it sported as a juvenile.
Black-and-white Warbler
The plumage of the Black-and-white Warbler lacks any of the vibrant colors found in the rainbow, but is nevertheless strikingly beautiful.
Black-and-white Warbler
This male Black-and-white Warbler appears a little bit ruffled as he dries out his feathers following a brief afternoon downpour. 
Black-and-white Warbler
But as the sunshine returns, he bursts into song from a forest perch within the nesting territory he has chosen to defend.  In addition to the vocalizations, this eye-catching plumage pattern helps advertise his presence to both prospective mates and would-be trespassers alike.  But against the peeling bark of massive trees where this bird can often be found quietly feeding in a manner reminiscent of a nuthatch, the feathers can also provide a surprisingly effective means of camouflage.  

Photo of the Day

Cedar Waxwing Feeding on Juneberries
One of dozens of Cedar Waxwings seen descending upon ripe juneberries in a mini grove consisting of either Smooth Shadbush (Amelanchier laevis) or the allied and very similar-looking hybrid juneberry Amelanchier x lamarkii.  Smooth Shadbush can be grown as a shrub or small tree and is also known as Smooth Serviceberry, Allegheny Serviceberry, or Smooth Juneberry.  The hybrid Amelanchier x lamarkii is believed to be a naturally occurring cross between Smooth Shadbush (A. laevis) and either Canadian Serviceberry (A. canadensis) or Downy Serviceberry (A. arborea).  Juneberries/serviceberries/shadbushes, including a number of man-made cultivars, produce white flowers in early spring and can be obtained through numerous suppliers for inclusion in conservation projects, home gardens, or for use as street trees.  Believe it or not, the very productive planting seen here was located in a parking lot island at a busy Walmart store.

Beechnuts in a Jam

Renowned for its smooth, light-gray bark and its large size, the American Beech is one the most easily recognized trees found in climax forests throughout the lower Susquehanna valley.  Preferring rich soils, this shade tolerant native produces an abundance of nutritious nuts for wildlife including deer, turkey, grouse, squirrels, woodpeckers, and a variety of songbirds.

If you’ve visited a stand of beech trees lately, you may have noticed that the canopy seems a little sparse in comparison to the foliage of the oaks, poplars, and other hardwood species in the vicinity.

American Beech Canopy
Sunlight reaching the forest floor through gaps in the canopy of American Beech trees.

A closer look reveals the cause.  And yes, it’s big, big trouble.

American Beech with Beech Leaf Disease
Many newly emerged leaves on this American Beech are thickened and curling in comparison to apparently healthy leaves on the same branch.  These sickly leaves are being afflicted by Beech Leaf Disease (BLD), the result of infection by a parasitic roundworm, Litylenchus crenatae mccannii, a microscopic nematode that reaches its greatest abundance within the victim’s new buds.  After increasing their population density there during the summer and fall, the nematodes overwinter within the dormant buds, then cause progressive cell damage in the foliage that emerges during the spring to make the leaves appear “striped” before withering and falling away.
American Beech with Beech Leaf Disease
Early season leaves on an American Beech perishing from infection by Litylenchus crenatae mccannii, the nematode responsible for Beech Leaf Disease.  BLD also affects Oriental Beech (Fagus orientalis) and European Beech (F. sylvatica), both imported to North America for ornamental cultivation.  BLD was first detected Lake County, Ohio, during 2012 and has already spread to every county in Pennsylvania and into much of the northeastern United States and neighboring portions of Canada.  The nematode responsible for BLD possibly originated among F. orientalis stocks in Japan, but its exact origins remain unconfirmed.
Beech Infected by Litylenchus crenatae mccannii
Cell damage from Litylenchus crenatae mccannii makes the new foliage on this American Beech appear “striped” before total deterioration.
Stand of American Beech with BLD
A sparse canopy in a stand of native American Beech trees being destroyed by the nematode, Litylenchus crenatae mccannii.  Defoliation over a period of 5 to 8 years will probably prove fatal to trees of this size.  Smaller trees may succumb in just 2 to 4 years.  Other sources of stress such as the extended period of drought we recently experienced may hasten the demise of afflicted trees.

While treatment for BLD is possible, it must be done early.  Protecting an entire stand in a forest can be prohibitively expensive, but if you have a specimen tree or small grove you think you might like to save, click here for a Penn State Extension guide with more information.

A Doe and Newborn Fawn Get Acquainted

An encounter from yesterday afternoon—you see it just the way we did…

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

Odocoileus virginianus Doe and Fawn

You know, there’s no better time than the present to slow down and quit driving like a sociopath.  After all, you wouldn’t want to murder Bambi’s mom and leave him all alone right now, would you?

Deer Tick or Dog Tick?

Deer Tick vs. Dog Tick
Several weeks back, we removed the tick on the left from the editor’s neck.  Upon returning from an outing earlier today, he discovered the one on the right crawling up his sock.  It’s almost like they’re out to get him, so after tossing the day’s apparel into the washer, it was time to hit the showers posthaste.  Because where there’s one, there are more.  And you absolutely never want to spend the night with a tick.

Late May Action in the Forest

Here’s a short preview of some of the finds you can expect during an outing in the Lower Susquehanna River Watershed’s forests this week…

Mountain Laurel
The Mountain Laurel, designated as Pennsylvania’s state flower, is now in bloom.
Mountain Laurel Flower Buds
The buds of the Mountain Laurel remind us of a sugary frosting freshly squeezed from a baker’s pastry bag.
Mountain Laurel Flowers
The flowers of the Mountain Laurel, an evergreen understory shrub, invite pollinators to stop by for a sweet treat.
Little Wood-Satyr
Little Wood-Satyrs (Megisto cymela) are patrolling forest edges looking for mates and, to host their eggs and larvae, the stands of grasses they find most suitable.
Zabulon Skipper
Many of the species of small butterflies we call skippers are now active. The Zabulon Skipper can be found patrolling grassy forest edges, particularly near streams, ponds, and wetlands.
Red-spotted Purple
Among the showiest of our butterflies, the Red-spotted Purple (Limenitis arthemis astyanax) is seen here on the leaves of a Black Cherry, its favored host plant.
Red-spotted Purple
Another red-spotted Purple seen picking up minerals from a dried up puddle depression on a gravel road.
Susquehanna Riverlands State Park
Butterfly observers will do well to pay a visit to the new Susquehanna Riverlands State Park on Furnace Road north of Hellam in York County, Pennsylvania.
Trail to Schull's Rock Overlook
Upon arrival at Susquehanna Riverlands, drive back the gravel road for about a mile to the parking area at the edge of the agricultural field.  Then, hike the trail through the woods and farm hedgerow to the Schull’s Rock overlook on the river.  In the forests along this route, the understory is dominated by colonial stands of Common Pawpaw trees.
Common Pawpaw
Along the lookout trail to Schull’s Rock, the Common Pawpaws’ large leaves help them to shade out potentially fast-growing competition.  In proper growing situations, pawpaws develop clonal suckers that mature over time to create colonial stands of a single genetic plant.
Common Pawpaw understory.
A Common Pawpaw understory along the approach to Schull’s Rock.
Common Pawpaw
A colonial stand of Common Pawpaw along the trail leading to Schull’s Rock.
Zebra Swallowtail
During our recent visit to Schull’s Rock, dozens of Zebra Swallowtails were seen along the trail, many in the vicinity of their sole host plant, the Common Pawpaw.  But even more were observed along the edges of the fields and woods where nectar sources like this Multiflora Rose were being visited by numbers of butterflies we normally see only among abundant species like Cabbage Whites.  Absolutely amazing!
Scull's Rock Overlook
And the view of the Susquehanna and the Shock’s Mills railroad bridge at the mouth of Codorus Creek is pretty good too!
Common Pawpaw and Hooded Warbler
You can look for colonial stands of Common Pawpaw at other parks and preserves along the lower Susquehanna as well.  Birds like this Hooded Warbler can sometimes be found among them in mature riparian forests along the steep slopes of the river gorge.
Common Pawpaw and Baltimore Oriole
A Baltimore Oriole in a Common Pawpaw along a forest edge.
Blackpoll Warbler
Meanwhile in the treetops, the spring thrust of Neotropical migrants is drawing to a close.  The Blackpoll Warbler is typically one of the last to transit the lower Susquehanna valley on its way to northern coniferous forests for summer.  They’ve had an unusually protracted movement through the region this spring, the earliest individuals reported during late April.  Though very difficult to see in the canopy of the mature trees where it feeds and sings, hearing one is often a benchmark for senior birders each spring.  Older observers have often said of the Blackpoll Warbler’s high-pitched song, a rapid series of insect-like staccato “tseet” notes, that it was the first they could no longer detect as their ears started losing sensitivity.
American Redstart
In many tracts along the lower Susquehanna this spring, the American Redstart is turning out to be the most common nesting warbler.  Conditions favoring their reproductive success in recent cycles, as well as good survival rates during their migrations and stays on wintering grounds, have filled many lowland forests with redstart songs in 2025.  Is this the start of a trend or just an exceptionally good year?  Time will tell.
Rose-breasted Grosbeak
Yet one more reason for a stroll in local forests this week is the chance to see and hear the Rose-breasted Grosbeak.  Look for these Neotropical relatives of the cardinal nesting on territories in mature stands of deciduous trees like this Yellow Poplar, a species also known as the Tuliptree.
They spend nearly all their time among the canopy foliage of the largest timber…
Rose-breasted Grosbeak
…but pause frequently to repeat a song often described as something akin to that which might be performed by a robin subjected to voice lessons.  The Rose-breasted Grosbeak is certainly a bird worth seeing and hearing.

Five Flowering Plants for Cleaner Water

Currently in the Lower Susquehanna River Watershed, you can find these five species of herbaceous plants in full bloom.  As they grow, they and others like them help to purify waters within their respective ecosystems by taking up nutrients—namely, the nitrogen and phosphorus that can lead to detrimental algal blooms and eutrophication in ponds, lakes, streams, and rivers.

(United States Geological Survey image by Virginia-West Virginia Science Center)
Marsh Blue Violet
The Marsh Blue Violet (Viola cucullata) is most frequently found growing in the wet soils of forest bottomlands, usually where springs first break the earth’s surface and begin slowly trickling away to form a small brook or join an existing stream.  The blooms are recognized by their darker purple centers and their long stems.
Marsh Blue Violet
This particular Marsh Blue Violet was found at 750′ altitude in the running water at a mountainside spring seep on a south-facing slope in the Ridge and Valley Province.
Soft Rush
The seldom-noticed flowers of the Soft Rush (Juncus effusus), also known as the Common Rush, emerge from the sides of its quill-like stems.  This wetland species is found in damp soils, sometimes in standing water, and grows in stiff, erect clumps that persist through winter.  When found in pastures, Soft Rush is seldom of interest to cattle or other livestock.  It therefore doesn’t lure these animals into muddy, puddle-prone areas.  When subjected to heavy grazing in dry weather and flooding during wet spells, these puddle sites may host nearly pure stands of Soft Rush, the only plant able to thrive there.  When it comes to nutrient uptake in these soggy sections of the meadow, the soft Rush is the lone ranger.  Soft Rush seeds are available from Ernst Conservation Seeds in Meadville, PA, and are included in many of their mixes formulated for stormwater management basins and other wet soil applications.
Larger Blue Flag
Larger Blue Flag (Iris versicolor) is a plant of wetlands and shorelines.  It can be grown as an emergent in ponds and lakes where it will help to absorb nutrients from both the water and the underlying substrate.
Larger Blue Flag
Larger Blue Flag is a native species in the lower Susquehanna valley.
Yellow Iris
The Yellow Iris (Iris pseudacorus), also known as the Water Flag, is native to Eurasia and Africa.  Seen here growing as an emergent among native Common Cattails (a superb water purifier), the Yellow Iris can easily escape cultivation and become invasive.  The showy flowers and water-cleansing benefits of this plant make it attractive for use in the garden or farm pond, but considerations must be made for its aggressive growth and proclivity to escape to neighboring habitats.  If you’re purchasing irises for transplanting, you’re probably better off sticking with the native Larger Blue Flag; it is far less vigorous and you’ll be able to grow other aquatic species along with it.
Spatterdock
In large ponds, lakes, and low-gradient streams, one of the best aquatic plants for sequestering nutrients and clarifying water is Spatterdock, also known as Cow-lily or Yellow Pond Lily.  Spatterdock does best as an emergent in shallow water along the shoreline.  It grows well in full sunshine and makes excellent habitat for wildlife.  Depending on the nutrient load from fish, waterfowl, decaying vegetation, and other sources, plant cover may need to be as high as 30% or more of the surface area to keep algae from overtaking a lake or large pond.  Spatterdock can often be used to help fulfill these needs while still offering open water beneath the leaves and between the stems for fish, amphibians, reptiles, and macroinvertebrates to thrive.
Spatterdock
Though probably not suitable for small garden ponds, Spatterdock (Nuphar advena) can be an excellent choice for helping to clear up the nutrient-loaded waters of a farm pond or lake.  You can find it, the irises, and Soft Rush available through some pond nurseries and garden centers.  If you can’t get them locally, check out retail and wholesale suppliers online, but remember to inspect any livestock you bring in from outside the area for hitchhikers like non-native snails (native snails are O.K.).  To be safe, always quarantine and monitor your aquatic plants for 30 days.  Tubers can be given a bath in 3% hydrogen peroxide solution for up to five minutes, then rinsed with water.  Repeat the treatment as needed until no snails or eggs are seen.  Another option: local pond owners who have them may be willing to divide some Iris and/or Spatterdock tubers and provide them for sale or gift to those who ask.  Just a couple will get you started.

Back in the Day: Down on the Farm

Let us travel through time for just a little while to recall those sunny, late-spring days down on the farm—back when the rural landscape was a quiet, semi-secluded realm with little in the way of traffic, housing projects, or industrialized agriculture.  Those among us who grew up on one of these family homesteads, or had friends who did, remember the joy of exploring the meadows, thickets, soggy springs, and woodlots they protected.

Low-intensity Farming
During much of the twentieth century, low-intensity agriculture provided a haven for wildlife.  Periodic disturbances helped maintain cool-season grassland and early successional habitat for a number of species we currently find in decline.

For many of us, farmland was the first place we encountered and began to understand wildlife.  Vast acreage provided an abundance of space to explore.  And the discovery of each new creature provided an exciting experience.

Distributed by the Pennsylvania Game Commission, artist Ned Smith’s wildlife posters introduced many residents of the lower Susquehanna region to its birds and mammals.  This poster of “Birds of Field and Garden” helped us learn what to expect and search for during our forays to the farm.

Today, high-intensity agriculture, relentless mowing, urban sprawl, and the increasing costs and demand for land have all conspired to seriously deplete habitat quality and quantity for many of the species we used to see on the local farm.  Unfortunately for them, farm wildlife has largely been the victim of modern economics.

For old time’s sake, we recently passed a nostalgic afternoon at Middle Creek Wildlife Management Area examining what maintenance of traditional farm habitat has done and can do for breeding birds.  Join us for a quick tour to remember how it used to be at the farm next door…

Barn Swallow
Always found nesting under the forebay of the barn, the Barn Swallow relentlessly pursued flying insects over the pond and meadow.
Eastern Meadowlark
Eastern Meadowlarks arrived during March and April to begin nesting in their namesake.  Their song, “spring-of-the-year”, heralded the new season.
Eastern Kingbird
Arriving in meadows and pastures during early May, the Eastern Kingbird provided for its nestlings by ambushing a variety of flying insects.  By August, congregations of these birds could be found gathering along ponds and streams ahead of their fall migration.
Orchard Oriole
In the cherry grove down by the creek, the Orchard Oriole would be singing incessantly to defend its territory.
American Goldfinches
Normally seed eaters through the colder months, American Goldfinches would regularly find a source of protein in the occupants of Eastern Tent Caterpillar nests.
Yellow Warbler
Along the wet margins of the creek, Yellow Warblers would nest in the shrubs and small trees.
Willow Flycatcher
The “Traill’s Flycatcher” was a familiar find in low-lying areas of successional shrubs and small trees.  Today, “Traill’s Flycatcher” is recognized as two distinct species, the Alder Flycatcher (Empidonax alnorum) and the Willow Flycatcher.  In the lower Susquehanna valley, the latter (seen here) is by far the most common of the two.
Eastern Bluebirds
During the nineteenth century, Eastern Bluebirds became a rarity on lower Susquehanna farms due to a combination of factors: pesticide (DDT) use, habitat loss, and competition with other birds for nest sites.  The species saw a resurgence beginning in the 1970s with discontinuation of DDT applications and widespread provision of nesting boxes.  Around human habitations, competition with invasive House Sparrows continues to be detrimental to their success.
Purple Martins and Tree Swallows
Purple Martins suffered a similar fate to the bluebirds.  The potential for their recovery remains dubious and they continue to be very local breeders, fussy about selection of suitable man-made provisions for nesting.  After considerable effort, Purple Martins have at last been attracted to nest in the condos placed for their use at Middle Creek Wildlife Management Area.  In the artificial gourds, there are nesting Tree Swallows, a species which also benefits from the placement of boxes intended for bluebirds.
Field Sparrow
Abandoned fields and other successional habitats were and continue to be favored homes for Field Sparrows.
Cedar Waxwing
At almost any time of year, roving bands of Cedar Waxwings would suddenly visit old field habitat looking for berries among the shrubs and other pioneering woody growth.  In early summer, after most species have already hatched their young, nesting would commence and these fruit eaters would transform into accomplished fly catchers.
Ring-necked Pheasant
During the twentieth century prior to the 1980s, Ring-necked Pheasant populations in the Lower Susquehanna River Watershed were comprised of breeding descendants of introduced birds supplemented by additional releases to maintain numbers sufficient for hunting.  Year-round populations did and can reside in mosaic landscapes of early successional and grassland habitats, the latter including hay fields left unmowed through the nesting season.
Red-winged Blackbird
Red-winged Blackbirds have always been a fixture of hay fields and meadows on farms.  While the increase in mowing frequency has reduced their nesting success, they have persevered as a species by nesting earlier than other birds and by utilizing other landscape features such as densely vegetated stormwater basins for breeding sites.
Bobolink
Do you recall the last time you saw a Bobolink nesting in a hay field near you?  Arriving in early May as a Neotropical migrant, the Bobolink requires a cool-season grassland such as hay field through at least July to complete its nesting cycle.  Even earlier this century, we remember nesting Bobolinks being more widespread on farms throughout the region.  Now, you almost have to go to Middle Creek if you want to see them.
Grasshopper Sparrow
Formerly more widespread in hay fields throughout the lower Susquehanna valley, the native Grasshopper Sparrow is yet another species falling victim to early mowing and intensive farming.
Grasshopper Sparrow
The solution to their dilemma is as advertised.  Instead of cutting the grass, why not take heed of the example set here and cut back on the tens of thousands of acres that are excessively or needlessly mowed in the Lower Susquehanna River Watershed?  How ’bout letting a significant percentage of your property regenerate as successional habitat as well?  It can and does make a difference!
Cool-season Grasses
Beautiful cool-season grasses waving in the spring breeze.  Meadows and hay fields can be managed to function as cool-season grasslands to provide nesting opportunities for many of the species we used to find down on the farm.

Photo of the Day

White-tailed Deer Button Buck Hosting Engorged Ticks
When it comes to sitting down and watching an episode of Hollywood Squares or indulging in a game of Tic-Tac-Toe, those of us here at susquehannawildlife.net are quick to play right along.  But when it comes to mixing it up with a Tick-Backed Doe or a Tick-Backed Buck like this one, you can count us out.  Upon finding this button buck infested with engorged Deer Ticks and heading our way on a grassy trail, we decided to turn around and limit our walk to the gravel roadway where there was less of a chance of picking up any hitchhikers from the vegetation where this guy has been spending his time.

Nest Builders at Work

For many animals, an adequate shelter is paramount for their successful reproduction.  Here’s a sample of some of the lower Susquehanna valley’s nest builders in action…

Pileated Woodpecker Excavating Nest
Many of our year-round resident bird species get a head start on the breeding season as cavity nesters.  Some of these mated pairs use naturally occurring hollows, while still others take advantage of the voids left vacant by the more industrious previous occupants.  Woodpeckers in particular are responsible for excavating many of the cavities that are later used as homes by a variety of birds and mammals to both rear their young and provide winter shelter.  Pileated Woodpeckers, like other members of the family Picidae, have an almost mystic ability to locate diseased or insect-infested trees for selection as feeding and nesting sites.  In this composite image, a pair is seen already working on a potential nursery during mid-January.  After use by the woodpeckers, abandoned cavities of this size can become nesting sites for a variety of animals including bees, small owls, Great Crested Flycatchers, Wood Ducks, Hooded Mergansers, and squirrels.
Downy Woodpecker at Nest
After use as a nesting site, a void excavated by Downy Woodpeckers can be occupied in subsequent years by chickadees, titmice, nuthatches, wrens, and other cavity-dwelling species.
Muskrat with Leafy Twig
This Muskrat (Ondatra zibethicus) with a leafy twig in tow takes advantage of spring’s new growth to construct or repair its house,…
Muskrat with Leafy Twig
…a process that can be repeated or renewed as necessary throughout the year.
Muskrat House
A Muskrat house in March.  In the absence of leafy twigs, dried cattail stems will suffice.  As it ages and decays, the house’s organic matter generates heat and makes an ideal location for turtles to deposit and hatch their eggs.
Wood Thrush
Soon after Neotropical migrants begin arriving in the forests of the lower Susquehanna watershed, they begin constructing their nests.  The majority of these species build “outdoors”, not within the confines of a tree cavity.  Here we see a Wood Thrush with its bill full of dried leaves and other materials…
Wood Thrush Nest
…ready to line the cup of its nest in the fork of a small understory tree.
Blue-gray Gnatcatcher
Though it often arrives during early April after spending the winter in sub-tropical and even some temperate climes, the Blue-gray Gnatcatcher must wait to start construction of its nest until many of the Neotropical migrants arrive in early May.
Blue-gray Gnatcatcher
You see, the Blue-gray Gnatcatcher relies on plenty of web-spinning spider activity to supply the construction materials it needs.
Blue-gray Gnatcatcher
A Blue-gray Gnatcatcher pulling apart a spider’s web on a warm May morning.
Blue-gray Gnatcatchers
Back at the nest site…
Blue-gray Gnatcatcher
…the sticky spider webs bind together lichens and small bits of bark…
Blue-gray Gnatcatcher
…to form a perfect little cup for the nesting Blue-gray Gnatcatchers.
Baltimore Oriole with Nesting Material
Baltimore Orioles weave one the most unique nests of any species occurring in eastern North America.
Baltimore Oriole Nest
Unfortunately for them, man-made litter can often seem to be the ideal material for binding the nest together.  In an area only sporadically visited by anglers, this oriole had no trouble finding lots of monofilament fishing line, trash that can fatally entangle both adult and young birds of any species.  If you see any fishing line at all, please pick it up and dispose of it properly.
Baltimore Oriole
Always keep an eye open for fishing line and get it before the birds do!
Brown-headed Cowbirds
Like many other avians, male Brown-headed Cowbirds are now relentlessly pursuing females of their kind.
Brown-headed Cowbirds
All his effort is expended in an attempt to impress her and thus have a chance to mate.
Brown-headed Cowbirds
This male can indeed put all his energy into the courtship ritual because Brown-headed Cowbirds toil not to build a nest.  They instead locate and “parasitize” the nests of a variety of other songbirds.  After mating, the female will lay an egg in a host’s abode, often selecting a slightly smaller species like a Yellow Warbler or native sparrow as a suitable victim.  If undetected, the egg will be incubated by the host species.  Upon hatching, the larger cowbird nestling will dominate the brood, often ejecting the host’s young and/or eggs from the nest.  The host parents then concentrate all their efforts to feed and fledge only the young cowbird.
Indigo Bunting
Watching and waiting.  The Indigo Bunting evades cowbird parasitism by first recognizing the invader’s egg.  They then either add a new layer of nest lining over it or they abandon the nest completely and construct a new one.  Some patient buntings may delay their breeding cycle until after cowbird courting behavior ceases in coming weeks.

Their Songs Give Them Away

After repeatedly hearing the songs of these Neotropical migrants from among the foliage, we were finally able to get a look at them—but it required persistent effort.

Magnolia Warbler
Often found closer to the ground among shrubs and small trees, this Magnolia Warbler was a challenge to find in the upper reaches of a Chestnut Oak.
Yellow-rumped Warbler
Not far away, we spied this Yellow-rumped Warbler.
Red-eyed Vireo
Despite its status as probably the most common Neotropical songbird to nest in the deciduous woodlands of the lower Susquehanna valley, the Red-eyed Vireo is nevertheless notoriously difficult to locate among the leaves.
Ovenbird
The Ovenbird spends much of its time on the forest floor where it builds a domed, oven-like nest.
Ovenbird
A fortunate observer may catch a glimpse of one perched in an understory shrub or small tree.
Ovenbird
But hearing the Ovenbird’s song, “teacher-teacher-teacher”, is frequently the only way to detect it.
Worm-eating Warbler
The Worm-eating Warbler nests in understory thickets on steep forested slopes.  Its rich chipping song is often the only indication of its presence.
American Redstart
Frequently easier to locate is the American Redstart, a Neotropical warbler that calls out its territory in damp woodlands from perches atop shrubs or among the lower limbs of trees.
Warbling Vireo
Warbling Vireos nest near streams or other bodies of water in large deciduous trees like this Northern Hackberry.
Gray Catbird
Gray Catbirds are abundant in shrubby gardens and thickets.  Most will come out of hiding to investigate disturbances like an observer making a pishing sound.
Common Yellowthroat
Another inhabitant of brushy successional growth is the Common Yellowthroat.  It too is curious and responds quickly to squeaky sounds made by human visitors to their home ground.
Yellow-breasted Chat
The Yellow-breasted Chat is a bird of early successional growth.  To establish and defend a breeding territory, this one adopted a perch along the edge of a woodlands overlooking a field in which prescribed fire was administered less than two months ago.
Yellow-breasted Chat
Like the mockingbird and thrasher, the Yellow-breasted Chat is a mimic.  Its song is a repertoire of the calls and songs of the bird species with which it may compete for food and nesting space.  Unique to the chat is an occasional pause, whistle, or “chuck” note that creates a bridge between many of its song’s elements.
Yellow-breasted Chat
The intensely territorial chat dropping down to look us over.

Sometimes we have to count ourselves lucky if we see just one in five, ten, or even twenty of the birds we hear in the cover of the forest canopy or thicket.  But that’s what makes this time of year so rewarding for the dedicated observer.  The more time you spend out there, the more you’ll eventually discover.  See you afield!

Scarlet Tanager
A singing Scarlet Tanager lurking in the shade of an oak.
Scarlet Tanager
Seeing is believing.

Singing in the Rain

Neotropical birds are fairly well acquainted with repetitive periods of thundershowers.  With that in mind, we decided not to waste this stormy Tuesday by remaining indoors.

Thundershower
Periods of rain need not put a damper on a day outdoors observing birds that wintered in a rain forest or other tropical environment.
Utility Right-of-way with Successional Habitat
We hiked this utility right-of-way to the north of a heavy thunderstorm and found plenty of activity in the shrubby successional habitat there.
Indigo Bunting
Rain or shine, male Indigo Buntings were busy singing.  All this exuberance is intended not only to establish and defend a nesting territory…
Indigo Bunting
…but to attract the attention of a mate as well.
Blue-winged Warbler
Prior to the implementation of the intensive manicuring practices we see currently applied to most utility right-of-ways, shrubby thickets filled miles of these linear corridors to create a webbed network of early successional growth throughout the lower Susquehanna valley.  Loss of this specialized habitat has led to the almost total elimination of the formerly common Blue-winged Warbler as a breeding species here.
Blue-winged Warbler
We found three male Blue-winged Warblers singing on territories in this bushy clearing where electric transmission lines pass over Third/Stony Mountain on State Game Lands 211.
Blue-winged Warbler
Their presence at this site is testament to the importance of maintaining corridors of quality successional habitat in the landscape.
Blue-winged Warbler
The Blue-winged Warbler is a Neotropical migrant with an easy-to-learn song.  It’s a very simple, buzzy sounding “beeee-bzzz”.
Prairie Warbler
Another Neotropical species that nests in successional thickets is the Prairie Warbler (Setophaga discolor), seen here during one of this morning’s downpours.
Prairie Warbler
The Prairie Warbler can sometimes be found in stands of pioneer plants like Eastern Red Cedar on sites with barren soils or those that have been subjected to wildfire.
Hooded Warbler
The Hooded Warbler is fond of wooded thickets along the edge of forested land such as those in the Third/Stony Mountain utility right-of-way.
Hooded Warbler
The presence of a Mountain Laurel thicket also enhances a forest’s ability to host breeding Hooded Warblers.

We hope you enjoyed our walk in the rain as much as we did.  If you venture out on a similar excursion, please remember this.  The majority of the wild animals around us have busy lives, particularly at this time of year.  Most don’t take a day off just because it rains—that includes ticks.

Female Deer Tick
Be certain to check yourself for ticks, especially these very small Deer Ticks (Ixodes scapularis), also known as Black-legged Ticks.  Deer Ticks are vigilantly looking for something to latch onto, even in the rain, and they can be vectors of Lyme disease.  We found this adult female as a stowaway on the editor’s neck just before heading home from today’s stroll.

Shad Run at Conowingo Dam

As the Flowering Dogwoods remind us, it’s time for adult sea-run shad and other fishes to ascend the Susquehanna to spawn.  So yep, we’re off to Fisherman’s Park on the river’s west shoreline below Conowingo Dam in Harford County, Maryland, to check it out.

Anglers at Conowingo Dam
Anglers were in the water and seeing action as we arrived below Conowingo Dam’s powerhouse at Fisherman’s Park.  The east lift, which was constructed during the 1990s to raise American Shad and other migratory fish over the dam during their spring spawning runs, sits idle at the impoundment end of the wing wall in the distance.
The entrance to the idle east fish lift at Conowingo Dam.
The entrance to the idle east fish lift at Conowingo Dam.
Northern Snakehead
Within minutes, we watched one of the culprits responsible for the lift’s shutdown being reeled in.  The invasive population of introduced Northern Snakeheads continues to thrive in the waters of the Susquehanna and its tributaries below the dam.  To prevent it from expanding its range to upriver sections of the watershed, all American Shad are being manually separated from among the snakeheads and other fish species deposited into sorting tanks using the west lift near the powerhouse.
Shad Transport Truck
One of several specialized transport vehicles returns from a “shad run” to the waters of the Susquehanna above York Haven Dam at Conewago Falls after delivering and releasing American Shad sorted from among the fish collected at Conowingo’s west lift earlier in the day.
American Shad began their run up the Susquehanna as water temperatures reached 60 degrees Fahrenheit…just about the time the Flowering Dogwoods started to bloom within the river’s riparian woodlands.  Later this month, spawning activity peaks when the water warms to about 65 degrees.  Earlier in the season, when the water reached about 55 degrees, another anadromous species, the Hickory Shad (seen here), began their spring spawning run from sea to freshwater rivers and streams.
While American Shad are seldom caught on hook and line, Hickory Shad are a popular catch-and-release target.  Though they will energetically strike baits like the small shad dart seen here, Hickory Shad are very cautious while ascending the river; they very rarely enter the fish lifts to join the dozens of other species that readily accept their use.  With water temperatures now in the sixties, an angler is seen here bringing in what may be among the last of this season’s Hickory Shad.  Their spawning run is presently drawing to a close for the year.
Gizzard Shad
The most commonly caught herring at Fisherman’s Park is the Gizzard Shad.  This plankton feeder seldom takes bait; it is instead foul-hooked.  Though not a sea-run species, Gizzard Shad by the tens of thousands leave open waters to seek shallower flowing riffles and pools to spawn.
Gizzard Shad
Unlike the other herring occurring in the Susquehanna, the Gizzard Shad has a blunt, snub-nosed appearance to the snout. The mouth is small and often unnoticeable.
Gizzard Shad
The Gizzard Shad is the only species of Susquehanna herring that can legally be harvested.  All others are sea-run migrants in varying degrees of population peril and must be returned to the water without delay.
Gizzard Shad
Note the elongated last ray on the dorsal fin of this foul-hooked Gizzard Shad.  It’s a not-often-visible but nevertheless tell-tale field mark.
Double-crested Cormorant
Humans aren’t the only creatures attracted by the fish migration on the lower Susquehanna.  This is just one of hundreds of Double-crested Cormorants we watched during our visit.
Cormorant along the base of Conowingo Dam
Hungry cormorants gather along the base of the dam where ascending fish congregate and become further disoriented by water turbulence.
Double-crested Cormorants
Fishing efforts here can bring great success to these accomplished piscivores.
Double-crested Cormorant with Gizzard Shad
Latching onto an oversize Gizzard Shad can make you very popular with your peers.
Double-crested Cormorant with Gizzard Shad
So popular that you may never have the opportunity to eat your lunch.
Double-crested Cormorant with Gizzard Shad
Take it from this old bird: you’ve gotta swallow ’em fast, head first, tail and all.
Bald Eagle with Gizzard Shad
A Bald Eagle hauls off a Gizzard Shad.
Osprey with Gizzard Shad
An Osprey saw this Gizzard Shad swimming close enough to the water’s surface to dive in and snag it with its talons.
Bald Eagle with Gizzard Shad
And yet another successful Bald Eagle calls out to its mate as it approaches its nest and hungry young.
Striped Bass
An angler releases a small Striped Bass caught on a shad dart while fishing for Hickory Shad.  To reduce pressure on their populations during the spring spawning run, the “Striper” harvest is presently closed.  The fishing season resumes later this month in some areas, in June within others.  On the Susquehanna Flats and other Chesapeake Bay waters, Striped Bass are also known as “Rockfish”.
Angler in Action
This angler is reeling in a big one.
Channel Catfish
A nice Channel Catfish weighed in at about six pounds and was released.
White Perch
This angler brought in yet another interesting catch.
White Perch
The White Perch (Morone americana) is a bay species that ascends the Chesapeake’s tributaries to spawn during the spring.  On the lower Susquehanna, numbers of this relative of the Striped Bass are falling, very possibly due to depredation by invasive snakeheads, Blue Catfish, and Flathead Catfish.
Double-crested Cormorant with Blue Catfish
A Double-crested Cormorant does its duty and snatches up an invasive Blue Catfish.   Very large Blue Catfish exceeding 24 inches in length are becoming increasingly plentiful on the upper Chesapeake and its tributaries resulting in a significant negative impact on the aquatic ecosystems there.  Like the Northern Snakehead and Flathead Catfish, these invasive species are very palatable and anglers are encouraged to catch and keep as many as they like.
Maryland DNR sign at Fisherman’s Park.
Angler with Northern Snakehead
What can we do about the plague of Northern Snakeheads (Channa argus) in the Susquehanna?  Well, let’s start by answering a question with a question…Why deplete ocean stocks when you can follow this angler’s example and harvest excellent fillets while helping to control an invasive species at the same time?  And no, you don’t have to call them “Chesapeake Channa” if you don’t want to.  Though you will make us laugh if you start calling them “Susquehanna Channa” or  just “Susquechanna” from time to time.

Six Flowering Woody Plants

Here’s a look at six native shrubs and trees you can find blooming along forest edges in the lower Susquehanna valley right now.

Black Locust
The Black Locust (Robinia pseudoacacia), a member of the pea or legume family (Fabaceae), can be a dominant pioneer plant of sunny successional habitats, particularly on poor soils.  Nodules along its roots fix nitrogen to help facilitate the growth of the intermediate and climax species of trees and shrubs that replace the pioneers.  Initially armed with protective spines to reduce browsing, the Black Locust’s branches become mostly thornless as the tree matures.
Pinxter Flower
The Pinxter Flower, also known as the Pink Azalea, is certainly a contender for our most spectacular native blossoming shrub;…
Spicebush Swallowtail on Pinxter Flower
…this Spicebush Swallowtail seems to like it too.
Black Cherry
When in bloom, the Black Cherry is a common sight in regional woodlands.  Often seen already covered with blossoms when young and shrub-like, many of these trees will continue flowering and producing fruit throughout the decades required to reach a mature height of 60 feet or more.
Blackhaw
The Blackhaw is an understory shrub preferential to sun-dappled areas beneath a break in the forest canopy.  Pollinated flowers later produce clusters of blue-black berries for birds and other wildlife.
Common Pawpaw
It’s easy to overlook the flowers of the Common Pawpaw.  By the time the leaves are fully emerged and casting shade, blooming time is over.
Flowering Dogwood
Nowadays, the Flowering Dogwood is most frequently encountered as a transplanted cultivar in city and suburban landscapes.  In the wild, it is sparingly distributed throughout the region’s deciduous forests.  These slow-growing little trees produce bright red berries that are quickly seized by a variety of birds upon ripening in the fall.

Local old timers might remember hearing folklore that equates the northward advance of the blooming of the Flowering Dogwoods with the progress of the American Shad’s spring spawning run up the river.  While this is hardly a scientific proclamation, it is likely predicated on what had been some rather consistent observation prior to the construction of the lower Susquehanna’s hydroelectric dams.  In fact, we’ve found it to be a useful way to remind us that it’s time for a trip to the river shoreline below Conowingo Dam to witness signs of the spring fish migration each year.  We’re headed that way now and will summarize our sightings for you in days to come.

Flowering Dogwood
Tree blossoms open in response to the presence of adequate moisture and exposure to the warming effects of sunshine.  Shad ascend the Susquehanna to spawn in response to suitable river flow and increasing water temperature.  Sun and rain in the appropriate proportions can often conspire to synchronize otherwise unrelated events.  Hence, a Flowering Dogwood in bloom along the edge of a mature forest means it’s time to go check out the shad run.

Photo of the Day

Indigo Bunting
Brilliantly colored migrants continue to arrive from their tropical wintering grounds.  Look for the Indigo Bunting in thickets and other successional habitat.  They are particularly fond of seldom-manicured utility right-of-ways and railroads where males like this one can be seen singing from an exposed perch to defend a nesting territory and attract a mate.

Fresh Foliage and Plumes

Despite what seemed to be a chilly early spring, the bright green leaves that unfold to close the canopy of our deciduous forests were dense and casting shade by the last days of April.  For northbound migrants, this fresh foliage provides the cover they need for foraging, resting, and, for those that will stick around to breed in the lower Susquehanna valley, nesting.

We recall many occasions when sparse foliage during the first days of May seemed to delay the big push of Neotropical species, but the seasonal arrival of these birds in 2025 is thus far mostly ahead of schedule.  This absence of delay is due in part to the lushness of the oaks.  Some stands have not only leafed out, but are finished flowering and have added up to 12 inches of new branch growth.  We spent these early hours of May among the oaks.  Here’s a look at the Neotropical migrants and other species we found…

Cape May Warbler
Dozens of species of Neotropical warblers have arrived in the Lower Susquehanna River Watershed.  Some will nest locally while others will continue along flight paths that will ultimately take them far to our north.  We spotted this Cape May Warbler in the upper reaches of a Northern Red Oak feeding among its spent flowers.  Its destination: the spruce forests of northern New England and Canada.
Yellow-throated Vireo
Slightly larger than the warblers are the vireos, including this Yellow-throated Vireo that has arrived to nest in an oak-maple bottomland.
Baltimore Oriole
Always a fan favorite, we found this marvelously tropical Baltimore Oriole among the foliage of a flowering White Oak.
Red-tailed Hawk
This young Red-tailed Hawk has survived its first winter.  It appears to have learned from experience how to hunt from advantageous locations such as this Chestnut Oak along a utility right-of-way where prey may include numerous squirrels as well as mice and other small mammals.
American Kestrel
We were taking a break beneath this Pin Oak when suddenly an American Kestrel arrived to begin scolding a trespasser that was straying a bit too close to its nest;…
Northern Harrier
…the intruder, a Northern Harrier, soon took the hint and continued on its way.
Veery
While among the oaks, it pays to check the understory where Neotropical thrushes including the Veery are arriving to fill the forests with their melodious songs.
White-throated Sparrow
Following their nocturnal flights, the last of the season’s northbound White-throated Sparrows may presently be found spending the day in the cover of the oak woodland understory.

The movements of our migratory birds typically continue through much of the month of May.  And peak numbers of Neotropical species often occur sometime during the second week of the month.  But with habitat at the ready, favorable flight conditions could facilitate quick arrival and/or passage of the bulk of the remaining migrants during the coming week.  You may want to venture out sooner rather than later—but watch your step!

Mayapple
The Mayapple, a native wildflower also known as the Mandrake, is now in bloom among the oak leaf litter.
Canada Mayflower
And the Canada Mayflower (Maianthemum canadense), a native species also known as Wild Lily-of-the-valley, is blooming in moist mixed-oak forests.
White-crowned Sparrow
At the edge of an oak-maple woodland, we found this lingering White-crowned Sparrow foraging among the leaf litter and fresh, shiny foliage of Poison Ivy.  Songbirds can spend their days scratching the ground among these leaves of three.  If you do it, you’ll be scratching something else, and you may need an ocean of calamine lotion to boot!

Busy Bees

During a warm spell back in late March, adult Mason Bees began emerging from nest sites to begin mating.  During recent days, we photographed the fertile females as they continued the process that will produce the next generation of these fruit-friendly pollinators.

Mason Bee Nest Box
Mason Bees visiting a box stocked with blocks of wood wherein holes have been drilled to provide nesting cavities for the egg-laying females.
Osmia Mason Bee
Mason Bee populations using man-made nesting structures in our region include two non-native species.  Both show horn-like structures on the face, denoted here by the white hairline.  To pollinate orchard crops, Osmia cornifrons, the Horn-faced Bee, was intentionally introduced to the eastern United States from northern Asia in 1978.  Another early season pollinator, Osmia taurus, was accidentally introduced to North America from eastern Asia.  O. taurus was first reported in Maryland and West Virginia in 2002 and had reached Pennsylvania by 2006-2008.
Female Mason Bees at Nest
Inside a nest cavity, a female Mason Bee will deposit pollen balls and an egg within each cell she creates using mud partitions.  Cell by cell she fills the cavity with eggs and pollen.  When the cavity is full, a thicker mud plug is constructed to seal off the entrance.  After hatching, each larval bee will remain inside a cocoon within its individual cell consuming the enclosed pollen ball and maturing.  After passing the winter in the nest, the new generation of adults will emerge in the spring…outermost cell occupants first.
Mason Bee Excavating Nest
When reusing a nest cavity from a previous year, a female Mason Bee will excavate old partitions and other debris before starting her own nest.  This female is removing saw dust and is possibly enlarging the hole on this new block of wood that we drilled just a few weeks ago.
Mason Bees at Small Holes
The majority of our Mason Bees prefer 1/4-inch holes, but some use the smaller 3/16-inch ones.  Holes up to 3/8 of an inch in diameter are readily accepted by both Osmia cornifrons and taurus.
Packing Pollen and Eggs
A look at several female Mason Bees backed into their nest cavities to deposit eggs and pollen.  Note the load of pollen adhering to the abdomen of the head-first bee at the bottom of the image and the yellow residue around the entrance to the cavity above it.
Drosophila Fly at Mason Bee Nest Entrance
Before a female Mason Bee has a chance to seal up a cell or to plug up the entrance to the cavity, a Drosophila fly (left) or other nest raider may show up to plunder a portion of the stash of pollen.
Mason Bee Sealing a Nest Cavity
Once filled with cells, each containing an egg and a pollen cache, the mother bee seals the nest cavity with a wall of mud.
Mason Bee Sealing Cavity
A bee seals up a 3/16-inch cavity with a mud barricade.  Adult female Mason Bees may select smaller than usual holes to deposit eggs that will produce their smaller male young.
Mason Bee Closing Nest
Upon finishing the masonry job here, this female will move on to yet another cavity to deposit the balance of her fertilized eggs.
High-occupancy Mason Bee Nest
One week later, the Mason Bees’ work is done.
High-occupancy Mason Bee Nest
The adults are then soon to perish.  But meanwhile, the next generation begins hatching and growing within the protection of the nest.  We’ll see them early next spring.

Photo of the Day

Juvenile Eastern Cottontail
This petite Eastern Cottontail somehow found a path through weekend traffic to discover an abundant supply of lush green Indian Strawberry (Potentilla indica) leaves in the garden at susquehannawildlife.net headquarters.  The widely naturalized Indian Strawberry, also known as Mock Strawberry, is native to Asia.  It is most easily recognized by its bright yellow flowers which soon yield edible, but not very tasty, little red fruits.  I wonder, might the berries be more palatable if dipped in a melted-down chocolate bunny?  Food for thought, unless of course you have an aversion to hare in your romantic confections.

Coastal Waterfowl at the Capital City

In early April of each year, we like to take a dreary-day stroll along the Susquehanna in Harrisburg to see if any waterfowl or seabirds have dropped in for a layover before continuing their journey from wintering waters along the Atlantic seaboard to breeding areas well to our north and northwest.  As showers started to subside this Saturday morning past, here are some of the travelers we had the chance to see…

Mixed flock of scaup species.
Hundreds of scaup were feeding at mid-river.  To remain in suitable foraging habitat, the group is seen here flying upstream to the area of the Governor’s Mansion where they would commence yet another drift downstream to Independence Island before again repositioning to a favorable spot.
Lesser and Greater Scaup
By far, the majority of the ducks in this flock were Lesser Scaup showing white inner margins of the secondary flight feathers and more grayish margins in the primaries.  Several Greater Scaup, including the one denoted by the hairline in this image, could be detected by the presence of bright white margins not only in the secondary flight feathers, but extending through the primaries as well.
Lesser Scaup
A pair of Lesser Scaup feeding along the river shoreline at the Governor’s Mansion.  Both scaup species spend the colder months in bays and coastal estuaries, but the Lesser Scaup is the most likely to be found venturing inland to fresh water in the southern United States during winter.  The Lesser Scaup nests in the northwestern United States and in the southern half of Canada.  The Greater Scaup is the more northerly nesting species, spending its summers at the northern edges of the border provinces and beyond.
Common Loon
Common Loons spend the winter in Atlantic surf.  April is the best time to see them on the lower Susquehanna River as they drop in to rest and reenergize during a break in their annual northbound trip to nesting sites on the lakes and ponds left behind by the retreat of Pleistocene glaciers.
Buffleheads
We saw dozens of Buffleheads during our morning hike, often segregated into paired couples like this one.  Being cavity nesters, these migrating ducks are headed no further north than southern Canada, to lakes and ponds within forests, for the summer.
Male Harlequin Duck
Harlequin Ducks (Histrionicus histrionicus) spend the summer nesting on turbulent high-gradient streams in Canada and Greenland.  They mostly winter along rocky coastlines as far south as New England, but have adapted to feeding along man-made rock jetties in coastal New York and New Jersey.  This winter, they were seen along jetties and sea walls at least as far south as Cape Charles, Virginia, and the mouth of Chesapeake Bay.  During the past month, at least two Harlequin Ducks, including this male seen in flight on Saturday, have appeared on the river in the Harrisburg area, possibly as strays from this year’s wintering population at the mouth of the bay.  These ducks are very rare habitat specialists, possibly (according to Behrens and Cox, 2013) numbering less than 1,500 birds along the entire east coast.
Horned Grebe
In spring, the Horned Grebe transitions from a drab gray-brown winter (basic) plumage into rather surprisingly colorful breeding (alternate) plumage.
Adult Horned Grebe
An adult Horned Grebe in breeding (alternate) plumage.  Horned Grebes spend the winter on large rivers, bays, and ocean waters from Nova Scotia to Texas. They are presently on their way to breeding areas on ponds and lakes in Alaska and Canada west of Ontario.

If you want a chance to see these seldom-observed visitors to the lower Susquehanna at Pennsylvania’s capital city, try a morning walk along mid-town’s Riverfront Park from Maclay Street to Forster Street.  Also, try a stroll on City Island, particularly to the beach at the north end where you have a view of the mid-river areas upstream.  To have better afternoon light, try the river’s west shore along Front Street in Wormleysburg from the Market Street Bridge upstream to Conodoguinet Creek.  Once there, be certain to check the river from the Pennsylvania Fish and Boat Commission’s West Fairview Access Area at the mouth of the creek.  And don’t be afraid to visit on a gloomy day; you never know what you might find!

Eastern Phoebe
Don’t forget to check the trees along the river shoreline where early stonefly hatches can often attract hungry insectivores.  We found this and six other Eastern Phoebes crowded into the trees at water’s edge just upriver from the Governor’s Mansion during Saturday’s migrant fallout.

SOURCES

Behrens, Ken, and Cameron Cox.  2013.  Seawatching: Eastern Waterbirds in Flight.  Houghton Mifflin Harcourt Publishing Company.  New York, NY.

Early Season Wildflowers

Here are five common forest flowers that the average visitor to these environs may easily overlook during an early April visit.

Skunk Cabbage
The flowers of the Skunk Cabbage, a native member of the arum family, are contained within a spadix which is partially hidden inside the mottled maroon spathe at the base of the plant.  In late winter, the closed spathe generates its own heat to melt through frozen water and soils to make its appearance in streamside and spring-fed wooded wetlands, just ahead of the emergence of the large green leaves.
Common Spicebush
Common Spicebush is a native flowering shrub of damp woodland understories.  Later in the season, its foliage provides food for Spicebush Swallowtail caterpillars.  Pollinated blossoms yield bright-red oblong berries relished by a variety of birds in fall and winter.
Red Maple
The flowers of the indigenous Red Maple will soon generate the familiar helicopter-like winged seeds which readily distribute this native tree into new ground ranging from lowlands to the crests of our highest ridges.
Coltsfoot
Coltsfoot (Tussilago farfara) is non-native wildflower of Eurasian origin.  Reminding one at first glance of a dandelion, it is commonly seen blooming in disturbed areas of woodlands.  Coltsfoot often grows where it has little competition from other plants, such as among the debris left behind due to snow plowing and grading along forest roads.
Sweet Cherry
Though not particularly abundant, the non-native Sweet Cherry, an escape from cultivation, is widespread in forests and woodlots throughout the lower Susquehanna valley.  Sweet Cherry is believed to be an ancestor of the Sour Cherry (Prunus cerasus) and is frequently used as rootstock for orchard and garden varieties of this popular fruit.  Sweet Cherry is often called “Wild Cherry”, a name also applied to the Black Cherry, a native tree which blooms later in the spring.

Be certain to get out and enjoy this year’s blooming seasons of our hundreds of varieties of flowering plants.  But, particularly when it comes to native species,…

Photo of the Day

Palm Warbler
Colorful songbirds like this Palm Warbler are beginning to migrate through the lower Susquehanna valley on their way north.  Even when the weather is damp and gloomy, be certain to spend some time outdoors if you’d like the chance to see them.  Palm Warblers are most frequently found in damp thickets and streamside, but they’ll sometimes show up in densely vegetated parks and gardens during a springtime fallout.

Photo of the Day

Ring-necked Pheasant
A Ring-necked Pheasant forages among the fresh green growth two weeks to the day after prescribed fire was administered to this parcel at Middle Creek Wildlife Management Area to turn back plant succession and maintain grassland habitat.

Three Items to Add to Your Tacklebox to Be a Better Conservationist

Soon after their arrival during the late 1600s, the earliest trans-Atlantic human migrants to settle the Lower Susquehanna River Watershed began the process of eliminating many of our largest native fish species.  They started by extirpating nature’s steward of lowland streams and wetlands, the North American Beaver.  The beaver’s meticulously maintained dams and fisheries-friendly ponds were promptly replaced by man-made impoundments designed to permanently divert water for powering lumber and grain mills.  Behind these structures, silt deposits accumulated as the forests were clear cut and the land subjected to highly erosive farming methods.  Mill dams would eventually be located on nearly every mile of suitable low-gradient stream in the basin.  Populations of native coldwater fishes including Brook Trout were quickly lost or left isolated in scattered headwaters.

With their navigation of creeks blocked by nearly impenetrable mill dams, seasonally migratory freshwater and anadromous fish were denied access to their traditional spawning waters.  The latter then had their populations seriously depleted, and in some cases extirpated, following construction of hydroelectric dams on the lower Susquehanna during the first half of the twentieth century.  The loss these latter species, including the herrings, Striped Bass, and sturgeons, all of which attain great size only because of their ability to make a sea run to access the year-round food energy available in the Atlantic, constitute a tremendous reduction in the numbers, variety, and mass of fish occurring in the river and its tributaries.

Add to these events the various sources of pollution entering the lower Susquehanna’s waterways during the intervening years including acid mine drainage, agricultural nutrients and sediments, stormwater runoff, untreated domestic and industrial sewage, illegal dumping, pesticides, etc., and one can easily understand how the watershed’s native fishery was lost as a commercial, food, and recreational resource.

Presently, the effort to restore populations of self-sustaining anadromous fishes to the lower Susquehanna is stalled due to the presence of introduced invasive species, particularly Northern Snakeheads, in the river’s waters below Conowingo Dam.  Lifts that carry migrating fishes over the lower river’s hydroelectric dams during the spring run are shut down to avoid extending the range of the hoards of non-native snakeheads to waters upstream of their present location.  Any translocation of anadromous fish must now be completed by manually separating desired species from among the invaders and loading them into a tank truck for transport to waters upstream of the dams.  But Northern Snakeheads are currently so prevalent at Conowingo that they are overwhelming the lift used for collecting and sorting fish as well.

Any slight hope that had existed for a return of harvestable stocks of American Shad or other sea-run native species to the Susquehanna and its tributaries seems to be fading.  And widespread improvements to water quality that would promote reestablishment of sustained populations of native coldwater fishes like Brook Trout are strictly a long-range goal.

Recreational anglers, however, still remain in the game—but their reward is a bit of a booby prize.  To compensate fisherman for the loss of their quarry on the river and in streams, and to promote an interest in the fishing pastime and conserving waterways, the stocking of various species of “game fish” has been a continuous undertaking, particular since the middle decades of the twentieth century.  Some of these introductions are planned, others, like the release of Northern Snakeheads, are unsanctioned and outright illegal.  The one thing most introductions have in common is that they consist of hardy, aggressive, predatory fishes that are non-native species (or native transplants from watersheds such as the Mississippi).  Their presence, especially in large concentrations and particularly during the time immediately following introduction, can have a deleterious impact on native stream inhabitants.  Some introduced fish, the Flathead Catfish for example, are upon discovery deemed invasive species; others, like the Smallmouth Bass, escape such a label not because they lack negative impacts on stream communities and ecosystems, but because they have been present for extended periods of time and have thus been accepted as part of the local fishing culture.

Rainbow Trout

Rainbow Trout
Hatchery-raised Rainbow Trout stocked by the hundreds in a lower Susquehanna valley creek for angling.  The Rainbow Trout is native to the streams and rivers of the Pacific coast of North America.  An anadromous form is known as the “Steelhead”.  These sea-run trout with access to marine food sources during their growth years attain more than twice the size of freshwater forms and acquire oversized hooked jaws before ascending waterways to spawn.

The creation of recreational fisheries comprised of introduced species has certainly helped maintain an interest in the fishing hobby and in the conservation of waterways.  It has even been a driving force for spectacular restorations of streams that otherwise would have languished in an impaired condition with little in the way of diversity of species—native or non-native.  As anglers, we are especially indebted to those who’ve devoted their time, energies, and, in some cases, a lot of money to projects that specifically seek to reestablish native waterways within the challenging landscape of the Lower Susquehanna River Watershed.  With an eye on the future, perhaps now is a good time to join them and focus our passion for freshwater angling on steering fisheries management more toward the native ecosystems approach.  Quality instead of quantity.

In that spirit, here are three items we can add to our tackle boxes this season to be better fisheries conservationists, instead of our own worst enemies.

Lead-free Weights
Lead-free Weights-  Replace the lead in your tackle box with tungsten or other lead-free alternatives to eliminate the potential impact this poisonous metal can have on you and wildlife like waterfowl and Bald Eagles.  Make a special effort to rid your inventory of small pieces of shot that can easily be ingested by animals as they feed. 
Realistic Lures
Realistic Lures-  Add sport to your fishing by using artificial lures.  Today’s selections include very realistic versions of native fishes, crayfish, frogs, and other aquatic creatures.  Use these life-like imitations and you won’t need to harvest native minnows and other wildlife from populations that are already being subjected to negative impacts from stocked legions of predatory “game fish”.  You’ll also eliminate the risk of introducing non-native bait species into your favorite fishing waters!
Trash Bag
Trash Bag-  Always bring a trash bag and carry out your litter.  Be especially vigilant about monofilament fishing line.
Fisherman's Trash
Fishermen are their own worst enemies, so you’ll need to pick up after the other guy too.  Show the landowners and land managers who are our hosts a little consideration.

Best of luck this fishing season.  We hope your time outdoors will motivate you to get involved with efforts to keep your local waterways clean.  You might even be inspired to assist with projects that are planned or currently underway in the Lower Susquehanna River Watershed to restore stream segments, wetlands, and floodplains.  Many of these projects are grassroots efforts and they’d love to have your participation.  Your local county conservation district can steer you towards an active restoration group near you.  Give them a ring.

Rainbow Trout and "Golden Rainbow Trout"
Hatchery-raised Rainbow Trout and a “Golden Rainbow Trout” stocked for anglers in a restored segment of a stream in Lebanon County, Pennsylvania.  The “Golden Rainbow Trout”, also known as the “Banana Trout”, is a Rainbow Trout color variant developed through multi-generational selective breeding of offspring produced by crossing a typical male with a yellow-mottled female mutant discovered in a hatchery in West Virginia in 1955.  Today, “Golden Rainbow Trout” breed true, golden males crossed with golden females yielding golden young.  The less colorful “Palomino Rainbow Trout” is produced by crossing a “Golden Rainbow Trout” with a typical Rainbow Trout.

Save Money on Gas, Guaranteed

You’ve seen the advice on the internet and elsewhere—”add coke to your gas tank and lower your fuel consumption.”  While the sources vary in their claims, reductions as great as 55% are often reported.  But are these performance improvements real?  Time for a fact check.

April Fool in Action

Uncle Tyler Dyer and his old pal Bellwood Comstock, Jr., better known by those close to him as “Woodstock”, got together and decided to try it out.  For their test, Uncle Ty added a 20-ounce bottle of Coke to his tank while his science partner Woodstock tried a same-sized portion of Pepsi in his automobile.

Within days, the experiment had reached a definitive outcome.  To say the least, our test techs were absolutely stunned by the results.

“Man, we can’t believe it,” exclaimed Uncle Ty.

“Spending money on gas is the least of my worries now,” noted his buddy Woodstock.

Collectively, our dynamic duo is now cutting down on carbon emissions by hundreds of pounds every month.  When asked if there were any other benefits to dumping cola in the tank, Ty reminded us, “Oh, yeah, we’ve been getting great exercise, riding our bikes and walking everywhere we go.  Earlier this week, we hitchhiked to a used car lot looking for bargains.  Man, it was just like the old days!”

“You know,” joked Uncle Ty’s loyal sidekick Woodstock, “if everybody did this, it sure would help relieve traffic congestion too.”

Wildlife in the Burn Zone

During Saturday’s Prescribed Fire Demonstration at the Pennsylvania Game Commission’s Middle Creek Wildlife Management Area, we noticed just how fast some species of wildlife return to areas subjected to burns administered to maintain grassland habitat and reduce the risk of high-intensity blazes.

Back Fire Ignition during prescribed burn demonstration.
Pennsylvania Game Commission crews ignite a back fire to contain a prescribed burn along its downwind/upslope perimeter during a demonstration at Middle Creek Wildlife Management Area on Saturday.
Prescribed Fire Demonstration
Visitors observe a fire planned to maintain this section of the refuge as warm-season grassland.  A species with roots several feet deep, the light-colored vegetation is Indiangrass, a plant adapted to thrive following periodic episodes of wildfire.  Prescribed fire can be used to replace naturally occurring infernos with much safer controlled burns that eliminate successional and invasive plants to promote the establishment of Indiangrass and other native warm-season species including Big Bluestem, Little Bluestem, Switchgrass, and a variety of wildflowers as well.
Prescribed Fire Demonstration
Even as the fire reached its brief peak of intensity, we noticed birds already attracted to the site…
Tree Swallow
Dozens of recently arrived Tree Swallows swept in to patrol for flying insects as the burn was in progress.
Tree Swallow
One even stopped by to have a look inside the kestrel nest box as fire approached the dry stand of goldenrod on the slope behind.
Red-tailed Hawk
Red-tailed Hawks and other raptors, including nocturnal owls, are frequently the first visitors attracted to the scene of a prescribed burn or wildfire.  In grassland and successional habitats, they come looking for any vulnerable voles or mice that may be moving about looking for cover.

Eastern Meadowlarks

Eastern Meadowlarks

Eastern Meadowlarks
These three Eastern Meadowlarks spent the morning in the grassland areas adjacent to the prescribed fire site, mostly where a burn had been conducted one week prior.  During the demonstration, one even perched and sang from the oak trees in the museum/visitor’s center parking lot.

Following the Prescribed Fire Demonstration, we decided to pay a visit to some of the parcels where burns had been administered one week earlier on the north side of Middle Creek’s main impoundment.  We found a surprising amount of activity.

White-crowned and White-throated Sparrows
Apparently feeding upon slightly heat-treated seeds, sparrows were found by the dozens. White-crowned (left), White-throated (right), Song, and Savannah Sparrows were identified.
Downy Woodpecker
This Downy Woodpecker was finding something to its liking among the scorched leaves, stems, and twigs.
American Robins seem to find areas with lightly burnt vegetation and ash-dusted soil advantageous for finding invertebrates following a fire.
Mixed Flock of Blackbirds
We found this flock of Red-winged Blackbirds, Browned-headed Cowbirds, and a few European Starlings feeding throughout a grassland field cleared of early-successional growth by a prescribed fire administered one week ago.
Mixed Flock of Blackbirds
They seemed to favor gleaning seeds from among the lightly burned areas of the plot.
Eastern Meadowlark
Nearby, in an island of unburned grass in the same field, we found yet another Eastern Meadowlark, our fourth of the day.  High-intensity agriculture, particularly early hay mowing and pesticide treatments, have mostly eliminated this and other grassland species from modern farms.  Management practices like prescribed fire and delayed mowing (no spinning blades until at least early August) can maintain ideal grassland habitat for stunningly colorful blackbirds including nesting Eastern Meadowlarks, Bobolinks, and many other species as well.
American Kestrel at Nest Box
A male American Kestrel at a nest box located among Middle Creek’s warm-season and cool-season grassland habitats, the former maintained by prescribed fire, the latter by delayed mowing.

Early-spring Maples: Clouds of Color Across the Forest Canopy

By late winter, sunshine and warming temperatures awaken the sleeping maples of the lower Susquehanna basin and the sap begins to flow.  The new growing season is evident by the first days of spring when their swelling buds and flowers paint the drab gray canopy of deciduous woodlands with an overlying coat of red, orange, and maroon.

Red Maples in Early Spring
Red Maples, renowned for their vibrant autumn foliage, are just as conspicuous in the early spring landscape.
Eastern Gray Squirrel Feeding on Red Maple Buds
For birds and mammals like this Eastern Gray Squirrel, the buds and flowers of maples mean relief from the diminished natural food supplies that helped them survive winter’s worst.  The season of abundance has arrived and these animals instantly recognize this source of sweet, fresh energy, just in time for the breeding season.  The flowers of maples, which later in the spring yield those familiar helicopter-like seeds, are an important early season source of energy for many species of bees and other pollinators.