Swamp Sparrow – LIFE IN THE LOWER SUSQUEHANNA RIVER WATERSHED

January 3, 2024March 30, 2024

Birds of the Sunny Grasslands

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

Grasslands and Hedgerows — On this State Game Lands parcel, prescribed fire is used to maintain a mix of grasslands and brushy early successional growth. In nearby areas, both controlled fire and mechanical cutting are used to remove invasive species from hedgerows and the understory of woodlots. Fire tolerant native species then have an opportunity to recolonize the forest and improve wildlife habitat. This management method also reduces the fuel load in areas with the potential for uncontrolled wildfires.

The sun-dried fruits of a Common Persimmon tree found growing in a hedgerow. — The sun-dried fruits of a native Common Persimmon tree found growing in a hedgerow.

Savanna-like Grasslands — Just one year ago, mechanical removal of invasive trees and shrubs (including Multiflora Rose) on this State Game Land was followed by a prescribed fire to create this savanna-like grassland.

Hundreds of Song Sparrows were found in the grasses and thickets at both locations.

White-throated Sparrows were also abundant, but prefer the tangles and shrubs of the thickets.

Northern Mockingbirds were vigilantly guarding winter supplies of berries in the woodlots and hedgerows.

In grasses and tangles on wetter ground, about a dozen Swamp Sparrows were discovered.

The adult White-crowned Sparrow is always a welcome find.

Dark-eyed Juncos were encountered only in the vicinity of trees and large shrubs.

Several Savannah Sparrows were observed. Though they’re mostly found in treeless country, this particular one happened to pose atop a clump of shrubs located within, you guessed it, the new savanna-like grasslands.

A tiny bird, even when compared to a sparrow, the Winter Wren often provides the observer with just a brief glimpse before darting away into the cover of a thicket.

Standing Clump of Timber — Within grasslands, scattered stands of live and dead timber can provide valuable habitat for many species of animals.

A "snag" with an excavated nest cavity. — Woodpeckers and other cavity-nesting birds rely upon an abundance of “snags” (standing dead trees) for breeding sites.

This Red-bellied Woodpecker and about a dozen others were found in trees left standing in the project areas.

A Yellow-bellied Sapsucker soaks up some sun.

This very cooperative Pileated Woodpecker seemed to be preoccupied by insect activity on the sun-drenched bark of the trees. This denizen of mature forests will oft times wander into open country where larger lumber is left intact.

Just as things were really getting fun, some late afternoon clouds arrived to dim the already fading daylight. Just then, this Northern Harrier made a couple of low passes in search of mice and voles hidden in the grasses.

January 21, 2022August 15, 2022

Photo of the Day

Swamp Sparrows can be found year-round in the Lower Susquehanna River Watershed. They seldom occur far from water, this one spending its time in a dense stand of Common Cattails (Typha latifolia).

November 4, 2021August 14, 2023

A Visit to Bombay Hook National Wildlife Refuge

It’s surprising how many millions of people travel the busy coastal routes of Delaware each year to leave the traffic congestion and hectic life of the northeast corridor behind to visit congested hectic shore towns like Rehobeth Beach, Bethany Beach, and Ocean City, Maryland. They call it a vacation, or a holiday, or a weekend, and it’s exhausting. What’s amazing is how many of them drive right by a breathtaking national treasure located along Delaware Bay just east of the city of Dover—and never know it. A short detour on your route will take you there. It’s Bombay Hook National Wildlife Refuge, a quiet but spectacular place that draws few crowds of tourists, but lots of birds and other wildlife.

Bombay Hook National Wildlife Refuge is located just off Route 9, a lightly-traveled coastal road east of Dover, Delaware. Note the Big Bluestem and other warm season grasses in the background. Bombay Hook, like other refuges in the system, is managed for the benefit of the wildlife that relies upon it to survive. Within recent years, most of the mowed grass and tilled ground that once occurred here has been replaced by prairie grasses or successional growth, much to the delight of Northern Bobwhite (Colinus virginianus) and other species.

Let’s join Uncle Tyler Dyer and have a look around Bombay Hook. He’s got his duck stamp and he’s ready to go.

Uncle Ty’s current United States Fish and Wildlife Service Duck Stamp displayed on his dashboard is free admission to the tour road at Bombay Hook and other National Wildlife Refuges.

The refuge at Bombay Hook includes woodlands, grasslands, and man-made freshwater pools, but it is predominately a protectorate of thousands of acres of tidal salt marsh bordering and purifying the waters of Delaware Bay. These marshes are renowned wintering areas for an Atlantic population of Snow Goose known as the “Greater Snow Goose” (Anser caerulescens atlanticus). Witnessing thousands of these birds rising over the marsh and glowing in the amber light of a setting sun is an unforgettable experience.

Trails at various stops along the auto tour route lead to observation towers and other features. This boardwalk meanders into the salt marsh grasses and includes a viewing area alongside a tidal creek. Our visit coincided with a very high tide induced by east winds and a new moon.

During high tide, an Eastern Cottontail (Sylvilagus floridanus) seeks higher ground near the boardwalk and the wooded edge of the salt marsh.

As the tide rises, fast-flying shorebirds scramble from flooded mudflats in the salt marsh on the east side of the tour road.

When high tide arrives in the salt marshes, shorebirds and waterfowl often concentrate in the man-made freshwater pools on the west side of the tour road. Glaring afternoon sun is not the best for viewing birds located west of the road. For ideal light conditions, time your visit for a day when high tide occurs in the morning and recedes to low tide in the afternoon.

A view looking west into Shearness Pool, largest of the freshwater impoundments at Bombay Hook.

Bombay Hook has many secretive birds hiding in its wetlands, but they can often be located by the patient observer. Here, two Pied-billed Grebes feed in an opening among the vegetation in a freshwater pool.

One of Bombay Hook’s resident Bald Eagles patrols the wetlands.

American Avocets (Recurvirostra americana) gather by the hundreds at Bombay Hook during the fall. A passing eagle will stir them into flight.

An American Avocet, a delicate wader with a peculiar upturned bill.

As soon as the tide begins receding, shorebirds and waterfowl like these Green-winged Teal begin dispersing into the salt marshes to feed on the exposed mudflats.

The woodlands and forested areas of the refuge host resident songbirds and can be attractive to migrating species like this Yellow-rumped Warbler.

For much of its course, the tour road at Bombay Hook is located atop the dike that creates the man-made freshwater pools on the western edge of the tidal salt marsh. If you drive slowly and make frequent stops to look and listen, you’ll notice an abundance of birds and other wildlife living along this border between two habitats. Here, a Swamp Sparrow has a look around.

Savannah Sparrows are common along the tour road where native grasses grow wild.

Bombay Hook is renowned for its rarities. One of the attractions during the late summer and autumn of 2021 was a group of Roseate Spoonbills (Platalea ajaja), vagrants from the southern states, seen here with Great Egrets and Snowy Egrets (Egretta thula).

Roseate Spoonbills and Great Egrets at Bombay Hook.

Remember to go the Post Office and get your duck stamp. You’ll be supporting habitat acquisition and improvements for the wildlife we cherish. And if you get the chance, visit a National Wildlife Refuge. November can be a great time to go, it’s bug-free! Just take along your warmest clothing and plan to spend the day. You won’t regret it.

May 11, 2021May 13, 2021

Maximum Variety

You’ll want to go for a walk this week. It’s prime time to see birds in all their spring splendor. Colorful Neotropical migrants are moving through in waves to supplement the numerous temperate species that arrived earlier this spring to begin their nesting cycle. Here’s a sample of what you might find this week along a rail-trail, park path, or quiet country road near you—even on a rainy or breezy day.

The Black-throated Blue Warbler is one of more than two dozen species of warblers passing through the Lower Susquehanna River Watershed right now. Look for it in the middle and bottom branches of deciduous forest growth.

The Veery and other woodland thrushes sing a melodious song. Veerys remain through the summer to nest in damp mature deciduous forests.

The American Redstart, this one a first-spring male, is another of the variety of warblers arriving now. Redstarts nest in deciduous forests with a dense understory.

Adaptable inquisitive Gray Catbirds are here to nest in any shrubby habitat, whether in a forest or a suburban garden.

Blue-gray Gnatcatchers (Polioptilia caerulea) arrive in April, so they’ve been here for a while. They spend most of their time foraging in the treetops. The gnatcatcher’s wheezy call alerts the observer to their presence.

Look way up there, it’s a pair of Blue-gray Gnatcatchers building a nest.

The Eastern Phoebe, a species of flycatcher, often arrives as early as mid-March. This particular bird and its mate are already nesting beneath a stone bridge that passes over a woodland stream.

Orchard Orioles (Icturus spurius) are Neotropical migrants that nest locally in habitats with scattered large trees, especially in meadows and abandoned orchards.

In the lower Susquehanna region, the Baltimore Oriole is a more widespread breeding species than the Orchard Oriole. In addition to the sites preferred by the latter, it will nest in groves of mature trees on farms and estates, in parks, and in forest margins where the canopy is broken.

The Warbling Vireo (Vireo gilvus) nests in big trees along streams, often sharing habitat with our two species of orioles.

Eastern Towhees arrive in numbers during April. They nest in thickets and hedgerows, where a few stragglers can sometimes be found throughout the winter.

The Yellow-breasted Chat (Icteria virens) is a migrant from the tropics that sometimes nests locally in thorny thickets. Its song consists of a mixed variety of loud phrases, reminding the listener of mimics like catbirds, thrashers, and mockingbirds.

Thickets with fragrant blooms of honeysuckle and olive attract migrating Ruby-throated Hummingbirds. Look for them taking a break on a dead branch where they can have a look around and hold on tight during gusts of wind.

The Eastern Kingbird, a Neotropical flycatcher, may be found near fields and meadows with an abundance of insects. In recent years, high-intensity farming practices have reduced the occurrence of kingbirds as a nesting species in the lower Susquehanna valley. The loss of pasture acreage appears to have been particularly detrimental.

Savannah Sparrows (Passerculus sandwichensis) can be found in grassy fields throughout the year. Large parcels that go uncut through at least early July offer them the opportunity to nest.

Male Bobolinks have been here for just more than a week. Look for them in alfalfa fields and meadows. Like Savannah Sparrows, Bobolinks nest on the ground and will lose their eggs and/or young if fields are mowed during the breeding cycle.

Cattail marshes are currently home to nesting Swamp Sparrows. Wetlands offer an opportunity to see a variety of unique species in coming weeks.

Shorebirds like this Solitary Sandpiper will be transiting the lower Susquehanna basin through the end of May. They stop to rest in wetlands, flooded fields, and on mudflats and alluvial islets in the region’s larger streams. Many of these shorebirds nest in far northern Canada. So remember, they need to rest and recharge for the long trip ahead, so try not to disturb them.

January 1, 2020August 15, 2022

Clean Slate for 2020

Inside the doorway that leads to your editor’s 3,500 square foot garden hangs a small chalkboard upon which he records the common names of the species of birds that are seen there—or from there—during the year. If he remembers to, he records the date when the species was first seen during that particular year. On New Year’s Day, the results from the freshly ended year are transcribed onto a sheet of notebook paper. On the reverse, the names of butterflies, mammals, and other animals that visited the garden are copied from a second chalkboard that hangs nearby. The piece of paper is then inserted into a folder to join those from previous New Year’s Days. The folder then gets placed back into the editor’s desk drawer beneath a circular saw blade and an old scratched up set of sunglasses—so that he knows exactly where to find it if he wishes to.

A quick glance at this year’s list calls to mind a few recollections.

The 2019 bird list included 48 species, the 47 on the board plus Ruby-throated Hummingbird, which was logged on a slip of paper found tucked into the edge of the frame.

This Green Frog, photographed on New Year’s Day 2019, was “out and about” along the edge of the editor’s garden pond. Due to the recent mild weather, Green Frogs were active during the current New Year’s holiday as well.

On a day with strong south winds in late February or during the first two weeks of March, there is often a conspicuous northbound spring flight of migrating waterfowl, gulls, and songbirds that crosses the lower Susquehanna valley as it departs Chesapeake Bay. These Tundra Swans were among the three thousand seen from the garden patio on March 13, 2019. A thousand migrating Canada Geese, 500 Red-winged Blackbirds, numerous Ring-billed Gulls, and some Herring Gulls were seen during the same afternoon.

This juvenile Cooper’s Hawk was photographed through the editor’s kitchen window. From its favorite perch on this arbor it would occasionally find success snagging a House Sparrow from the large local flock. It first visited the garden in November, the species being absent there since early spring. Unlike previous years, there was no evidence of a breeding pair in the vicinity during 2019.

Plantings that provide food and cover for wildlife are essential to their survival. Native flowers including Trumpet Vine (Campsis radicans) and Partridge Pea provide nourishment for the Ruby-throated Hummingbirds that visit the editor’s garden, but they really love a basket or pot filled with Mexican Cigar (Cuphea ignea) too. The latter (seen here) can be grown as a houseplant and moved outdoors to a semi-shaded location in summer and early fall. But remember, it’s tropical, so you’ll need to bring it back inside when frost threatens.

A Swamp Sparrow is an unusual visitor to a small property surrounded by paved parking lots and treeless lawns. Nevertheless, aquatic gardens and native plants helped to attract this nocturnal migrant, seen here eating seeds from Indiangrass. It arrived on September 30 and was gone on October 2.

Before putting the folder back into the drawer for another year, the editor decided to count up the species totals on each of the sheets and load them into the chart maker in the computer.

Despite the habitat improvements in the garden, the trend is apparent. Bird diversity has not cracked the 50 species mark in 6 years. Despite native host plants and nectar species in abundance, butterfly diversity has not exceeded 10 species in 6 years.

It appears that, at the very least, the garden habitat has been disconnected from the home ranges of many species by fragmentation. His little oasis is now isolated in a landscape that becomes increasingly hostile to native wildlife with each passing year. The paving of more parking areas, the elimination of trees, shrubs, and herbaceous growth from the large number of rental properties in the area, the alteration of the biology of the nearby stream by hand-fed domestic ducks, light pollution, and the outdoor use of pesticides have all contributed to the separation of the editor’s tiny sanctuary from the travel lanes and core habitats of many of the species that formerly visited, fed, or bred there. In 2019, migrants, particularly “fly-overs”, were nearly the only sightings aside from several woodpeckers, invasive House Sparrows (Passer domesticus), and hardy Mourning Doves. Even rascally European Starlings became sporadic in occurrence—imagine that! It was the most lackluster year in memory.

The Tufted Titmouse was a daily visitor to the garden through 2018. This one was photographed investigating holes in an old magnolia there during the spring of that year. There were no Tufted Titmouse sightings in the garden in 2019. This and other resident species, especially cavity-nesters, appear to be experiencing at least a temporary decline.

Breeding birds including Northern Cardinals may have had a difficult year. In the editor’s garden, a pair were still feeding and escorting one of their young in early October. The infestation of the editor’s town by domestic house and feral cats may have contributed to the failure of earlier broods, but a lack of food is also a likely factor.

If habitat fragmentation were the sole cause for the downward trend in numbers and species, it would be disappointing, but comprehendible. There would be no cause for greater alarm. It would be a matter of cause and effect. But the problem is more widespread.

Although the editor spent a great deal of time in the garden this year, he was also out and about, traveling hundreds of miles per week through lands on both the east and the west shores of the lower Susquehanna. And on each journey, the number of birds seen could be counted on fingers and toes. A decade earlier, there were thousands of birds in these same locations, particularly during the late summer.

At about the time of summer solstice in June each year, Common Grackles begin congregating into roving summer flocks that will grow in size to assure their survival during the autumn migration, winter season, and return north in the spring. From his garden, the editor saw just one flock of less than a dozen birds during the summer of 2019. He saw none during his journeys through other areas of the Susquehanna valley. Flocks of one hundred birds or more did not materialize until the southbound movements of grackles passed through the region in October and November.

In the lower Susquehanna valley, something has drastically reduced the population of birds during breeding season, post-breeding dispersal, and the staging period preceding autumn migration. In much of the region, their late-spring through summer absence was, in 2019, conspicuous. What happened to the tens of thousands of swallows that used to gather on wires along rural roads in August and September before moving south? The groups of dozens of Eastern Kingbirds (Tyrannus tyrannus) that did their fly-catching from perches in willows alongside meadows and shorelines—where are they?

Several studies published during the autumn of 2019 have documented and/or predicted losses in bird populations in the eastern half of the United States and elsewhere. These studies looked at data samples collected during recent decades to either arrive at conclusions or project future trends. They cite climate change, the feline infestation, and habitat loss/degradation among the factors contributing to alterations in range, migration, and overall numbers.

There’s not much need for analysis to determine if bird numbers have plummeted in certain Lower Susquehanna Watershed habitats during the aforementioned seasons—the birds are gone. None of these studies documented or forecast such an abrupt decline. Is there a mysterious cause for the loss of the valley’s birds? Did they die off? Is there a disease or chemical killing them or inhibiting their reproduction? Is it global warming? Is it Three Mile Island? Is it plastic straws, wind turbines, or vehicle traffic?

The answer might not be so cryptic. It might be right before our eyes. And we’ll explore it during 2020.

In the meantime, Uncle Ty and I going to the Pennsylvania Farm Show in Harrisburg. You should go too. They have lots of food there.

November 23, 2017November 24, 2017

Culinary Reminder

It was a crisp clear morning with birdless blue skies. The migration has mostly drawn to a close; very little was seen despite a suitable northwest breeze to support a flight. There were no robins and no blackbirds. Not even a starling was seen today. The only highlights were a Bufflehead (Bucephala albeola) and a couple of Swamp Sparrows.

A Swamp Sparrow is coaxed from the dense leafy cover of the Riverine Grasslands of Conewago Falls.

CLICK ON THE LOGO FOR TODAY’S MIGRATION COUNT TOTALS

And now ladies and gentlemen, boys and girls, it’s time for a Thanksgiving Day culinary reminder from the local Conewago Falls Turkey…

“That’s the Conewago Falls Turkey Vulture if you don’t mind. And I’m here to remind you that this Thanksgiving, you don’t have to fight your way in there to get first pickings of the feast. Take it from me, let those flavors and aromas intensify over time. And juices, who needs juices? Let that stuff congeal so everything sticks to your ribs. Are you paying attention? I’m telling you, just back off, let the crowd die down, then get in there and devour those leftovers. They’re the best. You’ll thank me later!”

November 12, 2017July 1, 2018

Anthropoavians

Temperatures plummeted to well below freezing during the past two nights, but there was little sign of it in Conewago Falls this morning. The fast current in the rapids and swirling waters in flooded Pothole Rocks did not freeze. Ice coated the standing water in potholes only in those rocks lacking a favorable orientation to the sun for collecting solar heat during the day to conduct into the water during the cold nights.

On the shoreline, the cold snap has left its mark. Ice covers the still waters of the wetlands. Frost on exposed vegetation lasted until nearly noontime in shady areas. Insect activity is now grounded and out of sight. The leaves of the trees tumble and fall to cover the evidence of a lively summer.

The nocturnal bird flight is narrowing down to just a few species. White-throated Sparrows, a Swamp Sparrow (Melospiza georgiana), and Song Sparrows are still on the move. Though their numbers are not included in the migration count, hundreds of the latter are along the shoreline and in edge habitat around the falls right now. Song Sparrows are present year-round, migrate at night, and are not seen far from cover in daylight, so migratory movements are difficult to detect. It is certain that many, if not all of the Song Sparrows here today have migrated and arrived here recently. The breeding population from spring and summer has probably moved further south. And many of the birds here now may remain for the winter. Defining the moment of this dynamic, yet discrete, population change and logging it in a count would certainly require different methods.

Song Sparrows are now abundant in the brushy edges of fields and woodlands. They may even break into song on sunny days.

Diurnal migration was foiled today by winds from southerly directions and moderating temperatures. The only highlight was an American Robin flight that extended into the morning for a couple of hours after daybreak and totaled over 800 birds. This flight was peppered with an occasional flock of blackbirds. Then too, there were the villains.

They’re dastardly, devious, selfish, opportunistic, and abundant. Today, they were the most numerous diurnal migrant. Their numbers made this one of the biggest migration days of the season, but they are not recorded on the count sheet. It’s no landmark day. They excite no one. For the most part, they are not recognized as migrants because of their nearly complete occupation of North America south of the taiga. If people build on it or alter it, these birds will be there. They’re everywhere people are. If the rotten attributes of man were wrapped up into one bird, an “anthropoavian”, this would be it.

Meet the European Starling (Sturnus vulgaris). Introduced into North America in 1890, the species has spread across the entire continent. It nests in cavities in buildings and in trees. Starlings are aggressive, particularly when nesting, and have had detrimental impacts on the populations of native cavity nesting birds, particularly Red-headed Woodpeckers, Purple Martins (Progne subis), and Eastern Bluebirds. They commonly terrorize these and other native species to evict them from their nest sites. European Starlings are one of the earlier of the scores of introduced plants and animals we have come to call invasive species.

Noisy flocks of European Starlings are right at home on man-made structures in city and country.

Today, thousands of European Starlings were on the move, working their way down the river shoreline and raiding berries from the vines and trees of the Riparian Woodlands. My estimate is between three and five thousand migrated through during the morning. But don’t worry, thousands more will be around for the winter.