LIFE IN THE LOWER SUSQUEHANNA RIVER WATERSHED – Page 14 – A Natural History of Conewago Falls

November 30, 2021August 15, 2022

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 Within recent years, most of the mowed grass and tilled ground that once occurred here has been replaced by prairie grasses or successional growth, much to the delight of Northern Bobwhite (Colinus virginianus) and other species.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.

October 24, 2021November 4, 2021

A Visit to the Post Office, for Just One Stamp

It’s been more than a year and a half since Uncle Tyler Dyer has been on one of our outings. He’s been laying low, keeping to himself—to protect his health. So he was quite excited when we made our way to the Delaware coast to have a look at some marine and beach life at Cape Henlopen State Park.

Uncle Ty hadn’t visited the Atlantic shoreline here for almost two decades, and he was more than a bit startled at what he saw…

Cape Henlopen State Park has spectacular wild dunes and pine forests, but notice how clean the high-tide line is on the beach. This is not a good sign. During our walks, we found not one mollusk shell (clam, scallop, snail, etc.), skate egg case, whelk egg case, dead fish, or other sign of benthic life from the adjacent surf and sea.

We found the remains of Mole Crabs (Emerita talpoida), also known as sand fleas, a crustacean that burrows into the surf-washed sands of the beach, but there were no signs of life from deeper waters.

One of a dozen or so Lesser Black-backed Gulls (Larus fuscus) observed consuming Mole Crabs. There was little else for these birds to eat. Sanderlings (Calidris alba) and other shorebirds typically found foraging along the surf’s edge were totally absent.

Atlantic Ghost Crabs (Ocypode quadrata) live in the predominantly dry sands of the beach, above the high tide line. Missing were the remains of aquatic crabs, including Atlantic Horseshoe Crabs (Limulus polyphemus), and other invertebrates that are often found washing in with the tide.

If you want to see an Atlantic Horseshoe Crab, you may have no better option than to visit the aquariums at the state park’s nature center.

A nearly sterile beach might be delightful for barefoot sunbathers and the running of the dogs, but Uncle Ty isn’t the barefoot type. He likes his sandals and a slow peaceful stroll with plenty of flora and fauna to have a look at. We could tell he was getting bored. So we headed home.

Along the way, Uncle Ty asked to stop at the Post Office. He wanted to get a stamp. Thinking he was going to fire off a terse letter of protest to the powers that be about what he saw at the beach, we obliged.

Soon, Uncle Ty trotted down the steps of the Post Office with his stamp.

Uncle Tyler Dyer with his one stamp. The 2021-2022 Federal Duck Stamp is available at most local Post Offices. According to the United States Fish and Wildlife Service, ninety-eight percent of the $25 purchase price goes directly to acquiring and protecting wetland habitat.

Uncle Ty bought a duck stamp, so naturally we asked him when he decided to take up hunting. He explained, “Man, I gave that stuff up when I was thirteen. I’ve got the Thoreau/Walden mindset—hunting is something of an adolescent pursuit.”

It turns out Uncle Ty bought a duck stamp to support wetland acquisition and improvements, not only to benefit ducks and other wildlife living there, but to improve water quality. In Delaware, tidal estuary restoration work is underway at both the Prime Hook and Bombay Hook National Wildlife Refuges on Delaware Bay. These projects will certainly enhance the salt marsh’s filtration capabilities and just might improve the populations of benthic life in the bay and adjacent ocean at Cape Henlopen.

Uncle Ty tossed the stamp atop the dashboard and we were again on our way, but we weren’t going directly home. We made a stop along the way. A stop we’ll share with you next time.

October 19, 2021

Early Golden Eagles

Each autumn, Eastern Golden Eagles transit the Lower Susquehanna River Watershed as they make their way from nesting sites in eastern Canada to wintering ranges in the mountains of the eastern United States. The majority of these birds make passage during late October and early November, so when a Golden Eagle is observed at a local hawk watch during the month of September, it is a notable event. So far in 2021, both Waggoner’s Gap Hawk Watch north of Carlisle and Second Mountain Hawk Watch at Fort Indiantown Gap have logged early-season Golden Eagles, the former on the seventeenth of September and the latter just yesterday.

Two images of a distant Golden Eagle seen passing Second Mountain Hawk Watch on September 29th. Plumage indicates it is a “before-third-year” bird. Adult birds and birds born this year, the latter known as hatch-year or juvenile Golden Eagles, are the least likely to have already completed the journey from northern breeding territories to south-central Pennsylvania. This individual is very likely an immature Golden Eagle in its second year, but a view of the topside of the wings would be necessary to eliminate a hatch-year/juvenile bird as a possibility. Immature Golden Eagles, those birds in their second through fourth years, are the ones most at leisure to wander and show up as unanticipated visitors at unexpected times.

To learn more about identifying Golden Eagles and other birds of prey, be certain to click the “Hawkwatchers Helper: Identifying Bald Eagles and other Raptors” tab at the top of this page.

And for more specific information on Golden Eagles and how to determine their age, click the “Golden Eagle Aging Chart” tab at the top of this page.

September 28, 2021September 28, 2021

Migration Update

Can it be that time already? Most Neotropical birds have passed through the Lower Susquehanna River Watershed on their way south and the hardier species that will spend our winter in the more temperate climes of the eastern United States are beginning to arrive.

Here’s a gallery of sightings from recent days…

During the past two weeks, thousands of Broad-winged Hawks, including this adult bird, crossed the skies of the lower Susquehanna valley on their way to Central and South America for our winter.

A juvenile Broad-winged Hawk passes into the sunset during its first autumn migration.

Blackpoll Warblers are among the last of the Neotropical species to transit the region. They’ll continue to be seen locally through at least early October.

Blue-headed Vireos are the October vireo during the fall, the other species having already continued toward tropical forests for a winter vacation.

The lower Susquehanna region lies just on the northern edge of the wintering range of the Blue-gray Gnatcatcher, a species found nesting locally among treetops in deciduous woods. Look for their numbers to swell in coming days as birds from further north begin rolling through the region on their way south.

Sharp-shinned Hawks delight visitors at ridgetop hawk watches during breezy late-September and early-October days. They allow closer observation than high-flying Broad-winged Hawks due to their habit of cruising just above the treetops while migrating.

A Sharp-shinned Hawk glides over a lookout.

Late September/early October is falcon time at area hawk-counting stations, the Peregrine Falcon often being the most anticipated species.

Pale “Tundra Peregrines”, a subspecies that nests in the arctic, are strictly migratory birds in the Mid-Atlantic States. They are presently passing through on their way to South America. Like Neotropical songbirds, their long flights provide them with the luxury of never experiencing a winter season.

This Carolina Saddlebags and other migratory dragonflies, which normally leave the area by mid-September, are still lingering in the lower Susquehanna region, much to the pleasure of the falcons that feed upon them.

An male American Kestrel in pursuit of dragonflies found swarming around the lookout at Second Mountain Hawk Watch in Lebanon County, Pennsylvania.

A male American Kestrel stooping on a dragonfly.

Osprey will be among the birds of prey passing hawk watch sites during the coming two weeks. The first week of October often provides the best opportunity for seeing the maximum variety of raptors at a given site. On a good day, a dozen species are possible.

Seeing cinnamon-colored juvenile Northern Harriers is symbolic of the October migration flights.

In addition to raptors, resident Common Ravens are regularly sighted by observers at hawk watches and elsewhere during the fall season.

Hawk-counting stations sometimes log movements of Red-bellied Woodpeckers during late September and early October. This species has extended its range into the Lower Susquehanna River Watershed only during the past one hundred years, making these seasonal migration movements a recent local phenomenon.

Blue Jays are currently on the move with breeding birds from the forests of Canada and the northern United States moving south. Hundreds can be seen passing a given observation point during an ideal morning.

Blue Jays find a pile of peanuts to be an irresistible treat. Provide the unsalted variety and watch the show!

Be sure to click on these tabs at the top of this page to find image guides to help you identify the dragonflies, birds, and raptors you see in the Lower Susquehanna River Watershed…

- Damselflies and Dragonflies
- Birds of Conewago Falls
- Hawkwatcher’s Helper: Identifying Bald Eagles and other Raptors

See you next time!

September 20, 2021September 20, 2021

Broad-winged Hawk Flights Underway

The smoke has cleared—at least for now—and Broad-winged Hawks are being seen migrating across lower Susquehanna valley skies. Check out these daily counts from area hawk watches…

- Rocky Ridge County Park Hawk Watch northeast of York, Pennsylvania: 475 Broad-winged Hawks on Saturday, September 18th—including 388 during the two hours between noon and 2 P.M.
- Second Mountain Hawk Watch at Fort Indiantown Gap in Lebanon County, Pennsylvania: 300 Broad-winged Hawks on Wednesday, September 15th— one more than was tallied passing the site on the previous day.
- Waggoner’s Gap Hawk Watch on Blue Mountain north of Carlisle, Pennsylvania: 1,211 Broad-winged Hawks on Tuesday, September 14th and 1,485 on Sunday, September 19th.

Broad-winged hawks in a “kettle” formation gaining altitude on a thermal updraft above Second Mountain Hawk Watch before continuing on their migratory journey. “Kettling” can occur above any heat-generating surface on a sunny day, even a parking lot.

A migrating adult Broad-winged Hawk rising skyward.

A juvenile Broad-winged Hawk “feeding on the wing” consuming a dragonfly.

Additional Broad-winged Hawks are still working their way through the Mid-Atlantic States as they continue toward tropical wintering grounds. And there’s more. Numbers for a dozen other migratory hawk, eagle, and falcon species will peak between now and mid-November. Days following passage of a cold front are generally best—so do get out there and have a look!

You can check the daily hawk count numbers and find detailed information for lookout sites all across North America at hawkcount.org

And don’t forget to click the “Hawkwatcher’s Helper” tab at the top of this page to see a gallery of photos that can help you to identify, and possibly determine the age of, the many species of raptors that occur in the Lower Susquehanna River Watershed.

A juvenile Merlin clutching a dragonfly takes a late-afternoon break from its migration flight. Merlin numbers peak in early October.

September 13, 2021September 24, 2021

Smoky Skies in the Lower Susquehanna Region

During the coming two weeks, peak numbers of migrating Neotropical birds will be passing through the northeastern United States including the lower Susquehanna valley. Hawk watches are staffed and observers are awaiting big flights of Broad-winged Hawks—hoping to see a thousand birds or more in a single day.

During its passage through the Lower Susquehanna River Watershed, an adult Broad-winged Hawk sails over Second Mountain Hawk Watch in Lebanon County, Pennsylvania.

A hatch-year/juvenile Broad-winged Hawk gazes toward hawk watchers on the ground.

Broad-winged hawks feed on rodents, amphibians, and a variety of large insects while on their breeding grounds in the forests of the northern United States and Canada. They depart early, journeying to wintering areas in Central and South America before frost robs them of a reliable food supply.

The Carolina Saddlebags (Tramea carolina), this one photographed at Second Mountain Hawk Watch on September 8th, is the rarest of the lower Susquehanna region’s migratory dragonflies. Autumn Broad-winged Hawk movements coincide with southbound flights of the Carolina Saddlebags and the more numerous migratory dragonfly species: Common Green Darner, Wandering Glider, Twelve-spotted Skimmer, and Black Saddlebags. “Broad-wings” will often eat these and other dragonflies during migration and can sometimes be seen catching and feeding upon them while still soaring high overhead.

While migrating, Broad-winged Hawks climb to great altitudes on thermal updrafts and are notoriously difficult to see from ground level. Bright sunny skies with no clouds to serve as a backdrop further complicate a hawk counter’s ability to spot passing birds. Throughout the Lower Susquehanna River Watershed, the coming week promises to be especially challenging for those trying to observe and census the passage of high-flying Broad-winged Hawks. The forecast of hot and humid weather is not so unusual, but the addition of smoke from fires in the western states promises to intensify the haze and create an especially irritating glare for those searching the skies for raptors.

Smoke from fires along the California coast and in central Utah can be seen streaming east this morning. (NOAA/GOES image)

Smoke from western fires and humid air creates a band of haze in Ohio, Pennsylvania, New Jersey, and states to the south this morning. (NOAA/GOES image)

A migrating Broad-winged Hawk in the glare of a hazy sky. In addition to visibility problems, swarms of Spotted Lanternflies above the treetops make distant hawks difficult to discern for hawk watchers scanning the horizon with binoculars.

It may seem gloomy for the mid-September flights in 2021, but hawk watchers are hardy types. They know that the birds won’t wait. So if you want to see migrating “Broad-wings” and other species, you’ve got to get out there and look up while they’re passing through.

Migrating Ospreys typically fly low enough and are large enough to be spotted even during the haziest of conditions.

Bald Eagles like this fourth-year bird can ascend to great altitude, but their size usually prevents them from sneaking past a lookout unnoticed.

Peregrines escape notice not due to hazy sky conditions, but because they pass by so quickly. They’re being seen at local hawk watches now through October.

These hawk watches in the Lower Susquehanna River Watershed are currently staffed by official counters and all welcome visitors:

- Rocky Ridge County Park Hawk Watch—3699 Deininger Road off Mount Zion Road (Route 24) northeast of York, Pennsylvania.
- Second Mountain Hawk Watch—off Cold Spring Road on the grounds of Fort Indiantown Gap in Lebanon County, Pennsylvania.
- Waggoner’s Gap Hawk Watch—where Route 74 crosses Blue Mountain north of Carlisle, Pennsylvania.

—or you can just keep an eye on the sky from wherever you happen to be. And don’t forget to check the trees and shrubs because warbler numbers are peaking too! During recent days…

Northern Parula at Chiques Rock County Park in Lancaster County.

Black-and-white Warbler at Rocky Ridge County Park in York County.

Cape May Warbler at Chiques Rock County Park in Lancaster County.

Bay-breasted Warbler at Rocky Ridge County Park in York County.

September 11, 2021September 11, 2021

September 9, 2021September 9, 2021

Why This Week Your Editor Read Eric Hoffer Once Again

September 5, 2021August 12, 2023

Warblers Passing Through the Lower Susquehanna River Valley

Neotropical birds are presently migrating south from breeding habitats in the United States and Canada to wintering grounds in Central and South America. Among them are more than two dozen species of warblers—colorful little passerines that can often be seen darting from branch to branch in the treetops as they feed on insects during stopovers in the Lower Susquehanna River Watershed.

Being nocturnal migrants, warblers are best seen first thing in the morning among sunlit foliage, often high in the forest canopy. After a night of flying, they stop to feed and rest. Warblers frequently join resident chickadees, titmice, and nuthatches to form a foraging flock that can contain dozens of songbirds. Migratory flycatchers, vireos, tanagers, and grosbeaks often accompany southbound warblers during early morning “fallouts”. Usually, the best way to find these early fall migrants is to visit a forest edge or thicket, particularly along a stream, a utility right-of-way, or on a ridge top. Then too, warblers and other Neotropical migrants are notorious for showing up in groves of mature trees in urban parks and residential neighborhoods—so look up!

A Black-and-white Warbler descends into the tangles of the forest understory to search for a morning meal of insects or creepy-crawlies.

Success! Looks like a cranefly (Tipulidae).

A Black-throated Green Warbler high in the treetops.

Warblers often travel and feed in the company of other Neotropical species like this Red-eyed Vireo.

Get out and look for those Neotropical migrants now because, like this Canada Warbler, in just a few weeks they’ll be gone.

Be sure to visit the Birds of Conewago Falls page by clicking the “Birds” tab at the top of this page. There, you’ll find photographs of the birds, including warblers and other Neotropical migrants, that you’re likely to encounter at locations throughout the Lower Susquehanna River Watershed.

August 31, 2021May 20, 2024

Pick Up and Get Out of the Floodplain

The remnants of Hurricane Ida are on their way to the Lower Susquehanna River Watershed. After making landfall in Louisiana as a category 4 storm, Ida is on track to bring heavy rain to the Mid-Atlantic States beginning tonight.

Tropical Depression Ida moving slowly toward the northeast. (NOAA/GOES image)

Rainfall totals are anticipated to be sufficient to cause flooding in the lower Susquehanna basin. As much as six to ten inches of precipitation could fall in parts of the area on Wednesday.

Rainfall forecasts from the National Hurricane Center. (NOAA/National Hurricane Center image)

Now would be a good time to get all your valuables and junk out of the floodways and floodplains. Move your cars, trucks, S.U.V.s, trailers, and boats to higher ground. Clear out the trash cans, playground equipment, picnic tables, and lawn furniture too. Get it all to higher ground. Don’t be the slob who uses a flood as a chance to get rid of tires and other rubbish by letting it just wash away.

Vehicles parked atop fill that has been dumped into a stream’s floodplain are in double trouble. Fill displaces water and exasperates flooding instead of providing refuge from it. Better move these cars, trucks, and trailers to higher ground, posthaste.

Flooding not only has economic and public safety impacts, it is a source of enormous amounts of pollution. Chemical spills from inundated homes, businesses, and vehicles combine with nutrient and sediment runoff from eroding fields to create a filthy brown torrent that rushes down stream courses and into the Susquehanna. Failed and flooded sewage facilities, both municipal and private, not only pollute the water, but give it that foul odor familiar to those who visit the shores of the river after a major storm. And of course there is the garbage. The tons and tons of waste that people discard carelessly that, during a flood event, finds its way ever closer to the Susquehanna, then the Chesapeake, and finally the Atlantic. It’s a disgraceful legacy.

Now is your chance to do something about it. Go out right now and pick up the trash along the curb, in the street, and on the sidewalk and lawn—before it gets swept into your nearby stormwater inlet or stream. It’s easy to do, just bend and stoop. While you’re at it, clean up the driveway and parking lot too.

Secure your trash and pick up litter before it finds its way into the storm sewer system and eventually your local stream. It’ll take just a minute.

This is how straws and other plastics find their way to the ocean and the marine animals living there, so pick that stuff up! Did you know that keeping stormwater inlets clean can prevent street flooding and its destructive extension into the cellars of nearby homes and businesses?

There’s another straw. Pick it and the rest of that junk up now, before the storm. Don’t wait for your local municipality or the Boy Scouts to do it. You do it, even if it’s not your trash.

We’ll be checking to see how you did.

And remember, flood plains are for flooding, so get out of the floodplain and stay out.