Prescribed Fire: Controlled Burns for Forest and Non-forest Habitats

Homo sapiens owes much of its success as a species to an acquired knowledge of how to make, control, and utilize fire.  Using fire to convert the energy stored in combustible materials into light and heat has enabled humankind to expand its range throughout the globe.  Indeed, humans in their furless incomplete mammalian state may have never been able to expand their populations outside of tropical latitudes without mastery of fire.  It is fire that has enabled man to exploit more of the earth’s resources than any other species.  From cooking otherwise unpalatable foods to powering the modern industrial society, fire has set man apart from the rest of the natural world.

In our modern civilizations, we generally look at the unplanned outbreak of fire as a catastrophe requiring our immediate intercession.  A building fire, for example, is extinguished as quickly as possible to save lives and property.  And fires detected in fields, brush, and woodlands are promptly controlled to prevent their exponential growth.  But has fire gone to our heads?  Do we have an anthropocentric view of fire?  Aren’t there naturally occurring fires that are essential to the health of some of the world’s ecosystems?  And to our own safety?  Indeed there are.  And many species and the ecosystems they inhabit rely on the periodic occurrence of fire to maintain their health and vigor.

For the war effort- The campaign to reduce the frequency of forest fires got its start during World War II with distribution of this poster in 1942.  The goal was to protect the nation’s timber resources from accidental or malicious loss due to fire caused by man-made ignition sources.  The release of the Walt Disney film “Bambi” during the same year and the adoption of the Smokey the Bear mascot in 1944 softened the message’s delivery, but the public relations outreach continued to be a key element of a no-fire policy to save trees for lumber.  Protection and management of healthy forest ecosystems in their entirety has only recently become a priority.  (National Archives image)

Man has been availed of the direct benefits of fire for possibly 40,000 years or more.  Here in the Lower Susquehanna River Watershed, the earliest humans arrived as early as 12,000 years ago—already possessing skills for using fire.  Native plants and animals on the other hand, have been part of the ever-changing mix of ecosystems found here for a much longer period of time—millions to tens of millions of years.  Many terrestrial native species are adapted to the periodic occurrence of fire.  Some, in fact, require it.  Most upland ecosystems need an occasional dose of fire, usually ignited by lightning (though volcanism and incoming cosmic projectiles are rare possibilities), to regenerate vegetation, release nutrients, and maintain certain non-climax habitat types.

But much of our region has been deprived of natural-type fires since the time of the clearcutting of the virgin forests during the eighteenth and nineteenth centuries.  This absence of a natural fire cycle has contributed to degradation and/or elimination of many forest and non-forest habitats.  Without fire, a dangerous stockpile of combustible debris has been collecting, season after season, in some areas for a hundred years or more.  Lacking periodic fires or sufficient moisture to sustain prompt decomposition of dead material, wildlands can accumulate enough leaf litter, thatch, dry brush, tinder, and fallen wood to fuel monumentally large forest fires—fires similar to those recently engulfing some areas of the American west.  So elimination of natural fire isn’t just a problem for native plants and animals, its a potential problem for humans as well.

Indiangrass on Fire
Indiangrass (seen here), Switchgrass, Big Bluestem, and Little Bluestem are native species requiring periodic forms of disturbance to eliminate competition by woody plants.  These warm-season grasses develop roots that penetrate deep into the soil, sometimes to depths of six feet or more, allowing them to survive severe drought and flash fire events.  In the tall grass prairies, these extensive root systems allow these grasses to return following heavy grazing by roaming herds of American Bison (Bison bison).  Without these habitat disturbances, warm season grasslands succumb to succession in about seven years.  With their periodic occurrence, the plants thrive and provide excellent wildlife habitat, erosion control, and grazing forage.

To address the habitat ailments caused by a lack of natural fires, federal, state, and local conservation agencies are adopting the practice of “prescribed fire” as a treatment to restore ecosystem health.  A prescribed fire is a controlled burn specifically planned to correct one or more vegetative management problems on a given parcel of land.  In the Lower Susquehanna River Watershed, prescribed fire is used to…

      • Eliminate dangerous accumulations of combustible fuels in woodlands.
      • Reduce accumulations of dead plant material that may harbor disease.
      • Provide top kill to promote oak regeneration.
      • Regenerate other targeted species of trees, wildflowers, grasses, and vegetation.
      • Kill non-native plants and promote growth of native plants.
      • Prevent succession.
      • Remove woody growth and thatch from grasslands.
      • Promote fire tolerant species of plants and animals.
      • Create, enhance, and/or manage specialized habitats.
      • Improve habitat for rare species (Regal Fritillary, etc.)
      • Recycle nutrients and minerals contained in dead plant material.

Let’s look at some examples of prescribed fire being implemented right here in our own neighborhood…

Prescribed Fire
Prescribed fires are typically planned for the dormant season extending from late fall into early spring with burns best conducted on days when the relative humidity is low.
Prescribed Fire at Fort Indiantown Gap
Prescribed fire is used regularly at Fort Indiantown Gap Military Reservation in Lebanon County, Pennsylvania, to keep accumulations of woody and herbaceous fuels from accumulating on and around the training range areas where live ordinance and other sources of ignition could otherwise spark large, hard-to-control wildfires.
Prescribed Fire at Fort Indiantown Gap
Prescribed fires replace the periodic natural burns that would normally reduce the fuel load in forested areas.  Where these fuels are allowed to accumulate, south-facing slopes are particularly susceptible to extreme fires due to their exposure to the drying effects of intense sunlight for much of the year.  The majority of small oaks subjected to treatment by the prescribed fire shown here will have the chance to regenerate without immediate competition from other species including invasive plants.  The larger trees are mostly unaffected by the quick exposure to the flames.  Note too that these fires don’t completely burn everything on the forest floor, they burn that which is most combustible.  There are still plenty of fallen logs for salamanders, skinks, and other animals to live beneath and within.

 

Prescribed fire in grassland.
A prescribed fire in late winter prevents this grassland consisting of Big Bluestem and native wildflowers from being overtaken by woody growth and invasive species.  Fires such as this that are intended to interrupt the process of succession are repeated at least every three to five years.
Prescribed Fire to Control Invasive Species
In its wildlife food plots, prescribed fire is used by the Pennsylvania Game Commission to prevent succession and control invasive species such as Multiflora Rose, instead promoting the growth of native plants.
A woodlot understory choked with combustible fuels and tangles of invasive Multiflora Rose.
An example of a woodlot understory choked with combustible fuels and dense tangles of invasive Multiflora Rose.  A forester has the option of prescribing a dose of dormant-season fire for a site like this to reduce the fuel load, top kill non-native vegetation, and regenerate native plants.
Precribed Fire to Eliminate Woody Growth
A dose of prescribed fire was administered on this grassland to kill the woody growth of small trees beginning to overtake the habitat by succession.
Precribed Fire Education Sign at middle creek Wildlife Management Area
The Pennsylvania Game Commission employs prescribed fire at Middle Creek Wildlife Management Area and on many of their other holdings to maintain grasslands.
Prescribed fire is used to eliminate invasive species including Multiflora Rose from grasslands at Middle Creek W.M.A.  Annual burns on the property are conducted in a mosaic pattern so that each individual area of the grassland is exposed to the effects of fire only once every two to five years.  Without fire or some type of mechanical or chemical intervention, succession by woody trees and shrubs would take hold after about seven years.
Prescribed fire is planned for a fraction of total grassland acreage at Middle Creek W.M.A. each year.  Another section of the mosaic is targeted in the following year and yet another in the year that follows that.  Because burns are conducted in the spring, grassland cover is available for wildlife throughout the winter.  And because each year’s fire burns only a portion of the total grassland acreage, wildlife still has plenty of standing grass in which to take shelter during and after the prescribed fire.
Grasshopper Sparrow
Prescribed fire at Middle Creek W.M.A. provides grassland habitat for dozens of species of birds and mammals including the not-so-common Grasshopper Sparrow…
Ring-necked Pheasant
…and stocked Ring-necked Pheasants that do nest and raise young there.
Prescribed Burn Maintains Savanna-like Habitat
On a few sites in the Lower Susquehanna River Watershed , prescribed fire is being used to establish and maintain savanna-like grasslands.  This one, located on a dry, south-facing slope near numerous man-made sources of ignition, can easily be dosed with periodic prescribed burns to both prevent succession and reduce fuel accumulations that may lead to a devastating extreme fire.
Pitch Pines in Savanna-like Habitat
One year following a prescribed burn, this is the autumn appearance of a savanna-like habitat with fire-tolerant Pitch Pine (Pinus rigida), Bear Oak, warm-season grasses, and a variety of nectar-producing wildflowers for pollinators.  These ecosystems are magnets for wildlife and may prove to be a manageable fit on sun-drenched sites adjacent to man-made land disturbances and their sources of ignition.
Red-headed Woodpecker Adult and Juvenile
Savanna-like grasslands with oaks and other scattered large trees, some of them dead, make attractive nesting habitat for the uncommon Red-headed Woodpecker.
Wild Turkey in Savanna-like Habitat
Prescribed fire can benefit hungry Wild Turkeys by maintaining savanna-like grasslands for an abundance of grasshoppers and other insects in summer and improving the success of mast-producing oaks for winter.
Buck Moth
In the Lower Susquehanna River Watershed, the caterpillar of the rare Eastern Buck Moth feeds on the foliage of the Bear Oak, also known as the Scrub Oak, a shrubby species that relies upon periodic fire to eliminate competition from larger trees in its early successional habitat.
Leaves of the Bear Oak in fall.
Leaves of the Bear Oak in fall.  The Bear Oak regenerates readily from top kill caused by fire.
Reed Canary Grass
Reed Canary Grass (Phalaris arundinacea) is a native cool-season grass with a colorful inflorescence in spring.  But given the right situation, it can aggressively overtake other species to create a pure stand lacking biodiversity.  It is one of the few native species which is sometimes labelled “invasive”.
Prescribed Burn to Reduce Prevalence of Reed Canary Grass
Prescribed fire can be used to reduce an overabundance of Reed Canary Grass and its thatch in wetlands.  Periodic burning can help restore species diversity in these habitats for plants and animals including rare species such as the endangered Bog Turtle (Glyptemys muhlenbergii).
On the range areas at Fort Indiantown Gap in Lebanon County, Pennsylvania, disturbances by armored vehicles mimic the effects of large mammals such as the American Bison which periodically trampled grasses to prevent succession and the establishment of woody plants on its prairie habitat.  To supplement the activity of the heavy vehicles and to provide suitable habitat for the very rare Regal Fritillary (Speyeria idalia) butterflies found there, prescribed fire is periodically employed to maintain the grasslands on the range.  These burns are planned to encourage the growth of “Fort Indiantown Gap Little Bluestem” grass as well as the violets used as host plants by the Regal Fritillary caterpillars.  These fires also promote growth of a variety of native summer-blooming wildflowers to provide nectar for the adults butterflies.
Depiction of Pennsylvania's Last American Bison, Killed in Union County in 1801. (Exhibit: State Museum of Pennsylvania, Harrisburg)
A last record of a wild American Bison killed in Pennsylvania was an animal taken in the Susquehanna watershed in Union County in 1801.  The species is thereafter considered extirpated from the state.  Since that time, natural disturbances needed to regenerate warm-season grasses have been limited primarily to fires and riverine ice scour.  The waning occurrence of both has reduced the range of these grasses and their prairie-like ecosystems in the commonwealth.  (Exhibit: State Museum of Pennsylvania, Harrisburg)
A male Regal Fritillary on the range at Fort Indiantown Gap, where armored vehicles and prescribed fire provide suitable prairie-like habitat for this vulnerable species.
Honey Bee Collecting Minerals After Prescribed Burn
Prescribed fires return the nutrients and minerals contained in dead plant material to the soil.  Following these controlled burns, insects like this Honey Bee can often be seen collecting minerals from the ashes.
Fly Collecting Minerals from Burned Grasses
A Greenbottle Fly gathering minerals from the ash following a prescribed burn.

In Pennsylvania, state law provides landowners and crews conducting prescribed fire burns with reduced legal liability when the latter meet certain educational, planning, and operational requirements.  This law may help encourage more widespread application of prescribed fire in the state’s forests and other ecosystems where essential periodic fire has been absent for so very long.  Currently in the Lower Susquehanna River Watershed, prescribed fire is most frequently being employed by state agencies on state lands—in particular, the Department of Conservation and Natural Resources on State Forests and the Pennsylvania Game Commission on State Game Lands.  Prescribed fire is also part of the vegetation management plan at Fort Indiantown Gap Military Reservation and on the land holdings of the Hershey Trust.  Visitors to the nearby Gettysburg National Military Park will also notice prescribed fire being used to maintain the grassland restorations there.

For crews administering prescribed fire burns, late March and early April are a busy time.  The relative humidity is often at its lowest level of the year, so the probability of ignition of previous years’ growth is generally at its best.  We visited with a crew administering a prescribed fire at Middle Creek Wildlife Management Area last week.  Have a look…

Members of a Pennsylvania Game Commission burn crew provide visitors to Middle Creek Wildlife Management Area with an overview of prescribed fire.
Members of a Pennsylvania Game Commission burn crew provide visitors to Middle Creek Wildlife Management Area with an overview of prescribed fire and the equipment and techniques they use to conduct a burn.
Burn Boss Checking Weather
Pennsylvania Game Commission Southeast Region Forester Andy Weaver will fulfill the role of Burn Boss for administering this day’s dose of fire.  His responsibilities include assessing the weather before the burn and calculating a probability of ignition.
Burn Boss Briefing Crew
The Burn Boss briefs personnel with information on site layout, water supply location(s), places of refuge, emergency procedures, the event’s goals and plan of action, crew assignments, and the results of the weather check: wind from the northwest at 5 miles per hour, temperature 48 degrees, and the relative humidity 63%. Today’s patient is a parcel of warm-season grasses receiving a dose of fire to eliminate invasive non-native plants, woody growth, and thatch.  The probability of ignition is 20%, but improving by the minute.
Prescribed Fire Test Burn
To begin the burn, a test fire is started in the downwind corner of the parcel, which also happens to be the bottom of the slope.  Fuel ignition is good.  The burn can proceed.
Igniting the Fire
Crews proceed uphill from the location of the test fire while igniting combustibles along both flanks of the area being treated.
Prescribed Fire Crew Member with Equipment
A drip torch is used to ignite the dried stems and leaves of warm-season grasses and wildflowers.  Each member of the burn crew wears Nomex fire-resistant clothing and carries safety equipment including a two-way radio, a hydration pack, and a cocoon-like emergency fire shelter.
Wildfire ATV
An all-terrain vehicle equipped with various tools, a fire pump, hose, and a small water tank accompanies the crew on each flank of the fire.
Prescribed Fire
A mowed strip of cool-season grasses along the perimeter of the burn area is already green and functions as an ideal fire break.  While the drip torch is perfect for lighting combustibles along the fire’s perimeter, the paintball gun-looking device is an effective tool used to lob incendiaries into the center areas of the burn zone for ignition.
Effective Fire Break
With green cool-season grasses already growing on the trails surrounding the burn zone, very little water was used to contain this prescribed fire.  Where such convenient fire breaks don’t already exist, crews carry tools including chain saws, shovels, and leaf blowers to create their own.  They also carry flame swatters, backpack water pumps, shovels, and other tools to extinguish fires if necessary.  None of these items were needed to control this particular fire.
Halting the Process of Succession in a Grassland with Prescribed Fire
This fast-burning fire provides enough heat to damage the cambium layer of the woody tree and shrub saplings in this parcel being maintained as a grassland/wildflower plot, thus the process of succession is forestalled.  Burns conducted during previous years on this and adjacent fields have also controlled aggressive growth of invasive Multiflora Rose and Olives (Elaeagnus species).
Containing the Fire on the Flanks
Crews proceed up the slope while maintaining the perimeter by igniting dry plant material along the flanks of the burn zone.
The Crew Monitors the Burn
Ignition complete, the crews monitor the fire.
Prescribed Fire: Natural Mosaic-style Burn Pattern
The Burn Boss surveys the final stages of a safe and successful prescribed fire.  The fire has left behind a mosaic of burned and unburned areas, just as a naturally occurring event may have done.  Wildlife dodging the flames may be taking refuge in the standing grasses, so there is no remedial attempt to go back and ignite these areas.  They’ll be burned during prescribed fires in coming years.
Great Spangled Fritillary
By June, this grassland will again be lush and green with warm-season grasses and blooming wildflowers like this Common Milkweed being visited by a Great Spangled Fritillary.
Eastern Tiger Swallowtails on Joe-pye Weed.
And later in the summer, Eastern Tiger Swallowtails on Joe-pye Weed.
Indiangrass in flower in mid-summer.
Indiangrass in flower in mid-summer.
Bobolinks in Indiangrass
Bobolinks glow in the late August sun while taking flight from a stand of warm-season grasses maintained using springtime prescribed fire.  The small dots on the dark background at the top of the image are multitudes of flying insects, many of them pollinators.  The vegetation is predominately Indiangrass, excellent winter cover for birds, mammals, and other wildlife.

Prescribed burns aren’t a cure-all for what ails a troubled forest or other ecosystem, but they can be an effective remedy for deficiencies caused by a lack of periodic episodes of naturally occurring fire.  They are an important option for modern foresters, wildlife managers, and other conservationists.

Four Common Grasshoppers

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

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

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

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

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

CAROLINA GRASSHOPPER

Dissosteira carolina

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

DIFFERENTIAL GRASSHOPPER

Melanoplus differentialis

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

TWO-STRIPED GRASSHOPPER

Melanoplus bivittatus

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

RED-LEGGED GRASSHOPPER

Melanoplus femurrubrum

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

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

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

Shorebirds and More at Bombay Hook National Wildlife Refuge

Have you purchased your 2023-2024 Federal Duck Stamp?  Nearly every penny of the 25 dollars you spend for a duck stamp goes toward habitat acquisition and improvements for waterfowl and the hundreds of other animal species that use wetlands for breeding, feeding, and as migration stopover points.  Duck stamps aren’t just for hunters, purchasers get free admission to National Wildlife Refuges all over the United States.  So do something good for conservation—stop by your local post office and get your Federal Duck Stamp.

2023-2024 Federal Duck Stamp. Your Federal Duck Stamp is your free pass to visit the nation's National Wildlife Refuges including Bombay Hook National Wildlife Refuge on Delaware Bay near Smyrna, Delaware.
Your Federal Duck Stamp is your admission ticket for entry into many of the country’s National Wildlife Refuges including Bombay Hook National Wildlife Refuge on Delaware Bay near Smyrna, Delaware.

Still not convinced that a Federal Duck Stamp is worth the money?  Well then, follow along as we take a photo tour of Bombay Hook National Wildlife Refuge.  Numbers of southbound shorebirds are on the rise in the refuge’s saltwater marshes and freshwater pools, so we timed a visit earlier this week to coincide with a late-morning high tide.

Northern Bobwhite
This pair of Northern Bobwhite, a species now extirpated from the Lower Susquehanna River Watershed and the rest of Pennsylvania, escorted us into the refuge.  At Bombay Hook, they don’t waste your money mowing grass.  Instead, a mosaic of warm-season grasses and early successional growth creates ideal habitat for Northern Bobwhite and other wildlife.
Shearness Pool at Bombay Hook N.W.R.
Twice each day, high tide inundates mudflats in the saltwater tidal marshes at Bombay Hook prompting shorebirds to move into the four man-made freshwater pools.  Birds there can often be observed at close range.  The auto tour route through the refuge primarily follows a path atop the dikes that create these freshwater pools.  Morning light is best when viewing birds on the freshwater side of the road, late-afternoon light is best for observing birds on the tidal saltwater side.
Great Blue Heron
A Great Blue Heron at high tide on the edge of a tidal creek that borders Bombay Hook’s tour route at Raymond Pool.
Semipalmated Sandpipers
Semipalmated Sandpipers stream into Raymond Pool to escape the rising tide in the salt marsh.
Semipalmated Sandpipers and Short-billed Dowitcher
More Semipalmated Sandpipers and a single Short-billed Dowitcher (Limnodromus griseus) arrive at Raymond Pool.
Short-billed Dowitchers
Two more Short-billed Dowitchers on the way in.
Sandpipers, Avocets, Egrets, and Mallards
Recent rains have flooded some of the mudflats in Bombay Hook’s freshwater pools. During our visit, birds were often clustered in areas where bare ground was exposed or where water was shallow enough to feed.  Here, Short-billed Dowitchers in the foreground wade in deeper water to probe the bottom while Semipalmated Sandpipers arrive to feed along the pool’s edge.  Mallards, American Avocets, and egrets are gathered on the shore.
Short-billed Dowitchers
More Short-billed Dowitchers arriving to feed in Raymond Pool.
Semipalmated Sandpipers
Hundreds of Semipalmated Sandpipers gathered in shallow water where mudflats are usually exposed during mid-summer in Raymond Pool.
Hundreds of Semipalmated Sandpipers, several Short-billed Dowitchers, and some Forster’s Terns (Sterna forsteri) crowd onto a mud bar at Bear Swamp Pool.
Semipalmated Sandpipers, Forster's Terns, and a Short-billed Dowitcher
A zoomed-in view of the previous image showing a tightly packed crowd of Semipalmated Sandpipers, Forster’s Terns, and a Short-billed Dowitcher (upper left).
Short-billed Dowitchers
Short-billed Dowitchers wading to feed in the unusually high waters of Raymond Pool.
Short-billed Dowitchers, American Avocets, and a Snowy Egret
Short-billed Dowitchers, American Avocets, and a Snowy Egret in Raymond Pool.  A single Stilt Sandpiper (Calidris himantopus) can been seen flying near the top of the flock of dowitchers just below the egret.
Stilt Sandpiper among Short-billed Dowitchers
Zoomed-in view of a Stilt Sandpiper (Calidris himantopus), the bird with white wing linings.
American Avocets
American Avocets probe the muddy bottom of Raymond Pool.
Dunlin and Short-billed Dowitchers
Among these Short-billed Dowitchers, the second bird from the bottom is a Dunlin. This sandpiper, still in breeding plumage, is a little bit early.  Many migrating Dunlin linger at Bombay Hook into October and even November.
Least Sandpiper
This Least Sandpiper found a nice little feeding area all to itself at Bear Swamp Pool.
Lesser Yellowlegs
Lesser Yellowlegs at Bear Swamp Pool.
Lesser Yellowlegs
Lesser Yellowlegs at Bear Swamp Pool
Greater Yellowlegs
A Greater Yellowlegs at Bear Swamp Pool.
Caspian Tern
A Caspian Tern patrolling Raymond Pool.
Marsh Wren singing
The chattering notes of the Marsh Wren’s (Cistothorus palustris) song can be heard along the tour road wherever it borders tidal waters.
Marsh Wren Nest
This dome-shaped Marsh Wren nest is supported by the stems of Saltwater Cordgrass (Sporobolus alterniflorus), a plant also known as Smooth Cordgrass.  High tide licks at the roots of the cordgrass supporting the temporary domicile.
Seaside Dragonlet
By far the most common dragonfly at Bombay Hook is the Seaside Dragonlet (Erythrodiplax berenice).  It is our only dragonfly able to breed in saltwater.  Seaside Dragonlets are in constant view along the impoundment dikes in the refuge.
Red-winged Blackbird
Red-winged Blackbirds are still nesting at Bombay Hook, probably tending a second brood.
Bobolink
Look up!   A migrating Bobolink passes over the dike at Shearness Pool.
Mute Swans and Canada Geese
Non-native Mute Swans and resident-type Canada Geese in the rain-swollen Shearness Pool.
Trumpeter Swans
A pair of Trumpeter Swans (Cygnus buccinator) as seen from the observation tower at Shearness Pool.  Unlike gregarious Tundra and Mute Swans, pairs of Trumpeter Swans prefer to nest alone, one pair to a pond, lake, or sluggish stretch of river.  The range of these enormous birds was restricted to western North America and their numbers were believed to be as low as 70 birds during the early twentieth century.  An isolated population consisting of several thousand birds was discovered in a remote area of Alaska during the 1930s allowing conservation practices to protect and restore their numbers.  Trumpeter Swans are slowly repopulating scattered east coast locations following recent re-introduction into suitable habitats in the Great Lakes region.
Great Egret
A Great Egret prowling Shearness Pool.
Snowy Egret
A Snowy Egret in Bear Swamp Pool.
A hen Wood Duck (second from right) escorts her young.
Wood Ducks in Bear Swamp Pool.
Black-necked Stilt and young.
A Bombay Hook N.W.R. specialty, a Black-necked Stilt and young at Bear Swamp Pool.

As the tide recedes, shorebirds leave the freshwater pools to begin feeding on the vast mudflats exposed within the saltwater marshes.  Most birds are far from view, but that won’t stop a dedicated observer from finding other spectacular creatures on the bay side of the tour route road.

Bombay Hook National Wildlife Refuge protects a vast parcel of tidal salt marsh and an extensive network of tidal creeks. These areas are not only essential wildlife habitat, but are critical components for maintaining water quality in Delaware Bay and the Atlantic.
Atlantic Horseshoe Crab
The shells of expired Atlantic Horseshoe Crabs were formerly widespread and common among the naturally occurring flotsam along the high tide line on Delaware Bay.  We found just this one during our visit to Bombay Hook.  Man has certainly decimated populations of this ancient crustacean during recent decades.
As the tide goes out, it’s a good time for a quick walk into the salt marsh on the boardwalk trail opposite Raymond Pool.
Atlantic Marsh Fiddler Crabs
Among the Saltmarsh Cordgrass along the trail and on the banks of the tidal creek there, a visitor will find thousands and thousands of Atlantic Marsh Fiddler Crabs (Minuca pugnax).
Atlantic Marsh Fiddler Crabs
Atlantic Marsh Fiddler Crabs and their extensive system of burrows help prevent the compaction of tidal soils and thus help maintain ideal conditions for the pure stands of Saltwater Cordgrass that trap sediments and sequester nutrients in coastal wetlands.
Atlantic Marsh Fiddler Crab
A male Atlantic Marsh Fiddler Crab peers from its den.
Great Egret
Herons and egrets including this Great Egret are quite fond of fiddler crabs.  As the tide goes out, many will venture away from the freshwater pools into the salt marshes to find them.
Green Heron
A Green Heron seen just before descending into the cordgrass to find fiddler crabs for dinner.
Clapper Rail
A juvenile Clapper Rail (Rallus crepitans crepitans) emerges from the cover of the cordgrass along a tidal creek to search for a meal.
Glossy Ibis
Glossy Ibis leave their high-tide hiding place in Shearness Pool to head out into the tidal marshes for the afternoon.
Great Black-backed Gulls, Herring Gulls, and possibly other species feed on the mudflats exposed by low tide.
Great Black-backed Gulls, Herring Gulls, and possibly other species feed on the mudflats exposed by low tide in the marshes opposite Shearness Pool.
Ospey
An Osprey patrols the vast tidal areas opposite Shearness Pool.

No visit to Bombay Hook is complete without at least a quick loop through the upland habitats at the far end of the tour route.

Indigo Bunting
Indigo Buntings nest in areas of successional growth and yes, that is a Spotted Lanternfly on the grape vine at the far right side of the image.
Blue Grosbeak
Blue Grosbeaks (Passerina caerulea) are common nesting birds at Bombay Hook.  This one was in shrubby growth along the dike at the north end of Shearness Pool.
Trumpet Creeper and Poison Ivy
These two native vines are widespread at Bombay Hook and are an excellent source of food for birds. The orange flowers of the Trumpet Vine are a hummingbird favorite and the Poison Ivy provides berries for numerous species of wintering birds.
Pileated Woodpecker in Sweet Gum
The Pileated Woodpecker is one of the numerous birds that supplements its diet with Poison Ivy berries.  The tree this individual is visiting is an American Sweetgum (Liquidambar styraciflua), a species native to the Atlantic Coastal Plain in Delaware.  The seed balls are a favorite winter food of goldfinches and siskins.
Red-bellied Slider and Painted Turtle
Finis Pool has no frontage on the tidal marsh but is still worth a visit.  It lies along a spur road on the tour route and is located within a deciduous coastal plain forest.  Check the waters there for basking turtles like this giant Northern Red-bellied Cooter (Pseudemys rubiventris) and much smaller Painted Turtle.
White-tailed Deity
The White-tailed Deity is common along the road to Finis Pool.
Fowler's Toad
Fowler’s Toads (Anaxyrus fowleri) breed in the vernal ponds found in the vicinity of Finis Pool and elsewhere throughout the refuge.
Turk's Cap Lily
The National Wildlife Refuge System not only protects animal species, it sustains rare and unusual plants as well.  This beauty is a Turk’s Cap Lily (Lilium superbum), a native wildflower of wet woods and swamps.
Wild Turkey
Just as quail led us into the refuge this morning, this Wild Turkey did us the courtesy of leading us to the way out in the afternoon.

We hope you’ve been convinced to visit Bombay Hook National Wildlife Refuge sometime soon.  And we hope too that you’ll help fund additional conservation acquisitions and improvements by visiting your local post office and buying a Federal Duck Stamp.

Photo of the Day

Wild Turkey
A warm weekend will give foraging Wild Turkeys a chance to continue finding protein-rich grasshoppers and crickets before freezing weather forces them to transition to seeds, berries, acorns, hickory nuts, and other fare for sustenance.  Watch for gobblers and hens in forest clearings while you’re out and about having a gander at the fall foliage.

Photo of the Day

It’s Gallo the Wild Turkey reminding you how delicious, nutritious, and filling macaroni and cheese can be as your center of the plate selection this holiday.  And if macaroni and cheese isn’t filling enough for you, there’s always filling.  But, remember, food safety experts remind us to never cook filling inside a bird.  So why invite a turkey to dinner?  Just eat more mac and cheese…and filling.  Gobble it up.

Coming Soon, Very Soon: Brood X Periodical Cicadas

Yesterday, a hike through a peaceful ridgetop woods in the Furnace Hills of southern Lebanon County resulted in an interesting discovery.  It was extraordinarily quiet for a mid-April afternoon.  Bird life was sparse—just a pair of nesting White-breasted Nuthatches and a drumming Hairy Woodpecker.  A few deer scurried down the hillside.  There was little else to see or hear.  But if one were to have a look below the forest floor, they’d find out where the action is.

Not much action in the deer-browsed understory of this stand of hardwoods.
Upon discovery beneath a rock, this invertebrate quickly backed its way down the burrow, promptly seeking shelter in the underground section of the excavation.
A closeup of the same image reveals the red eyes of this Periodical Cicada (Magicicada species) nymph.  It has reached the end of seventeen years of slowly feeding upon the sap from a tree root to nourish its five instars (stages) of larval development.

2021 is an emergence year for Brood X, the “Great Eastern Brood”—the largest of the 15 surviving broods of Periodical Cicadas.  After seventeen years as subterranean larvae, the nymphs are presently positioned just below ground level, and they’re ready to see sunlight.  After tunneling upward from the deciduous tree roots from which they fed on small amounts of sap since 2004, they’re awaiting a steady ground temperature of about 64 degrees Fahrenheit before surfacing to climb a tree, shrub, or other object and undergo one last molt into an imago—a flying adult.

Here, approximately one dozen Periodical Cicada nymphs have tunneled into pre-emergence positions beneath a rock.  Seventeen-year Periodical Cicadas, sometimes mistakenly called “seventeen-year locusts”, are the longest-lived of our insects.
Note the wings and red eyes beneath the exoskeleton of this Periodical Cicada nymph. Within weeks it will join billions of others in a brief emergence to molt, dry, fly, mate, and die.
Adult (imago) Periodical Cicadas.  Brood X includes all three species of seventeen-year Periodical Cicadas: Magicicada septendecim, M. cassinii, and M. septendecula.  All Periodical Cicadas in the United States are found east of the Great Plains, the lack of trees there prohibiting the expansion of their range further west.  Seventeen-year life cycles account for twelve of the fifteen broods of Periodical Cicadas; the balance live for thirteen years.  The range of Brood X includes the lower Susquehanna basin and parts of Delaware, Georgia, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, Ohio, Tennessee, Virginia, West Virginia, and the District of Columbia.  (United States Department of Agriculture/Agricultural Research Service image)
The flight of Periodical Cicadas peaks in late-May and June.  Shown here is the Eastern Scissor Grinder, an “Annual Cicada” that emerges later in the season, peaking yearly during July and August.

The woodlots of the Lower Susquehanna River Watershed won’t be quiet for long.  Loud choruses of male Periodical Cicadas will soon roar through forest and verdant suburbia.  They’re looking for love, and they’re gonna die trying to find it.  And dozens and dozens of animal species will take advantage of the swarms to feed themselves and their young.  Yep, the woods are gonna be a lively place real soon.

Did you say Periodical Cicadas?  We can hardly wait!

Fallout in the Lower Susquehanna River Watershed

Local birders enjoy going to the Atlantic coast of New Jersey and Delmarva in the winter.  The towns and beaches host far fewer people than birds, and many of the species seen are unlikely to be found anywhere else in the region.  Unusual rarities add to the excitement.

The regular seaside attraction in winter is the variety of diving ducks and similar water birds that feed in the ocean surf and in the saltwater bays.  Most of these birds breed in Canada and many stealthily cross over the landmass of the northeastern United States during their migrations.  If an inland birder wants to see these coastal specialties, a trip to the shore in winter or a much longer journey to Canada in the summer is normally necessary—unless there is a fallout.

Migrating birds can show up in strange places when a storm interrupts their flight.  Forest songbirds like thrushes and warblers frequently take temporary refuge in a wooded backyard or even in a city park when forced down by inclement weather.  Loons have been found in shopping center parking lots after mistaking the wet asphalt for a lake.  Fortunately though, loons, ducks, and other water birds usually find suitable ponds, lakes, and rivers as places of refuge when forced down.  For inland birders, a fallout like this can provide an opportunity to observe these coastal species close to home.

Not so coincidentally, it has rained throughout much of today in the Lower Susquehanna River Watershed, apparently interrupting a large movement of migrating birds.  There is, at the time of this writing, a significant fallout of coastal water birds here.  Hundreds of diving ducks and other benthic feeders are on the Susquehanna River and on some of the clearer lakes and ponds in the region.  They can be expected to remain until the storm passes and visibility improves—then they’ll promptly commence their exodus.

The following photographs were taken during today’s late afternoon thundershower at Memorial Lake State Park at Fort Indiantown Gap, Lebanon County.

A one-year-old male Hooded Merganser (Lophodytes cucullatus).
Red-breasted Mergansers (Mergus serrator) are a familiar sight in saltwater bays, not so familiar on inland bodies of water.
A small raft of Scaup (Aythya species).
A pair of Buffleheads.
A Common Loon that lands in a parking lot is unable to take flight again.  It must be transported to a body of water large enough for it to run across the surface and get the speed it needs to take off and resume its flight.  This Common Loon at Memorial Lake has selected an ideal fallout haven.  It will have plenty of runway space when it decides to leave.
A Pied-billed Grebe (Podilymbus podiceps) in a heavy downpour.

Migrating land birds have also been forced down by the persistent rains.

The tail-pumping Eastern Phoebe is a common sight around the lower Susquehanna valley right now.  Many will stay to breed, often building their nests under a man-made bridge, porch. or other structure.

Why not get out and take a slow quiet walk on a rainy day.  It may be the best time of all for viewing certain birds and other wildlife.

Wild Turkeys (Meleagris gallopovo) will often leave the cover of woodlands and forest to forage in the open during a rain shower.
During the final hours of this evening, wind-assisted flights of northbound migrating birds are indicated as blue masses around radar sites south of the Mason-Dixon Line.  These nocturnal flights may constitute yet another fallout in the area of the showers and storms shown passing west to east through Pennsylvania, adding to the existing concentration of grounded migrants in the lower Susquehanna valley.  (NOAA/National Weather Service image)