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contributed by Bob Cowgill
It’s Time to Close.
I hope that many of you enjoyed the stories presented in Wild Things over the past few years. I told the stories of the more glamorous animals such as the alligator, bobcat, deer and yes even that evanescent cougar. But I have attempted also to speak on behalf of some of the lesser known residents of the island such as the ghost shrimp, mole cricket and knobbed whelk, and even those held in low esteem, such as the bats, crows and snakes.
Each of these must be respected, for each has a special story to tell. Each is uniquely fitted through millions of years of evolution to play the role allotted to it on the stage that is Kiawah Island. This glorious pageant of life is ours to enjoy each day.
And now is a good time to close with an epilogue that appeared at the end of one of my books entitled Nature’s Way on Kiawah.
Thus we end this chapter in ongoing events on Kiawah.
Walk your own trails,
Make your own observations,
Build your own stories,
Of Nature’s Way on this wonderful planet,
Nature's Way of Stabilizing Our Beach.
Mats of brown reeds that may be seen on the beach in the spring serve a valuable role in stabilization. It is true that the mats are rather unsightly, and they do impede the progress of all - from sun bathers to nesting marine turtles. However, this inconvenience is more than adequately compensated by the large amount of sand retained on the beach by their presence.
This is done in two ways. The first and most obvious way is that the mats accumulate blown sand and begin the build-up of dunes, then as the tide rushes in the mats resist the removal of sand by the retreating water. The second way is less obvious but if one looks closely at the mats, tiny spots of new, green plants will be seen. Thus, the mats serve as a mulch and nursery for new vegetation that also will stabilize the beach, both by diminishing the force of wind and by resistance of the roots to removal of sand by extremely high tides.
This is part of a grand cycle that occurs annually. The reed mats originate in the marshes on the other side of the island. Marsh grass (Spartina alternaflora) sprouts early in the spring from the roots of the previous year’s growth and rises to heights of 4 to 6 feet. In winter the grass dies, and the dried reeds are washed out of the marsh by high tides the following spring. They are carried to the sea by the Kiawah River and distributed along our beach by the offshore currents. Thus the physical forces of wind and wave work in concert with the marsh plants to stabilize our island of sand.
The Ghost Crab Is Well Named.
On the Kiawah beach a crab scuttles swiftly along on tiptoes. Suddenly it halts, sinks down and blends into the sand so perfectly that you wonder if you saw it at all. It is well named the Ghost crab, for it seems to appear from nowhere and as suddenly disappear again. Only its beady black eyes set upon long stalks above the upright square-backed body may give it away. As the crab crouches motionless the eyestalks perform like the periscope of a submarine. They can not only swivel to view the beach at all 360 degrees but also tilt to provide excellent vision overhead.
It is not a
true marine crab, for it makes its home in a burrow in the dry sand of the upper
beach and cautiously approaches the water only when absolutely necessary. Yet
it is still totally dependent upon the sea, because it must carry a bit of the
ocean in a chamber surrounding its gills. Each day it must make several trips
to the waterline to wet its gills.
It does this with trepidation and makes the least possible contact with the sea. Instead of wading directly into the water, it will take up a position a little above the place where the waves are breaking on the beach. Standing sideways to the water, it awaits the one big wave that will run farther up the beach. As soon as the wave front has briefly washed over it, back it will hastily scramble to the security of the dry beach.
Although occasionally a few venture out in the daytime, they are primarily hunters and scavengers of the night beach. Relying on the cloak of darkness to bolster the courage they lack by day, they swarm out aggressively from their burrows. They feed mainly on small coquina clams that they locate, dig out of the sand and crush with their powerful claws. However, they accept almost anything as food, and diligently search out every scrap left on the beach. They are truly the sanitary engineers of the beach, along with the ants and the crows. None of these species are highly regarded, but their services are essential to keep our beach wholesome.
The Shell of the Knobbed Whelk
One of the most common shells that you are likely to encounter on the Kiawah beach is the heavy, cone-shaped shell of the Knobbed whelk. As you continue your beach-combing, you will find numerous fragments of the same shell that have washed ashore. This is a sure sign that the sandy floor off the beach is not a safe place even for an animal as heavily armored as our knobbed whelk.
What animal in the sea has jaws capable of crushing such an impregnable shell?
To my knowledge, the only animal capable of this destruction is the huge turtle that nests on our beach during the summer and is known to feed upon the crabs and whelks that it finds on the continental shelf.
But in addition to that formidable turtle, predatory mollusks beside the whelk prowl the sand beneath the waves, and each is capable of attacking the others. When you find the empty shell of a whelk on the beach, examine it closely. Sometimes you will find a small, perfectly round hole as though made by a steel drill bit. Probably this is the work of a moon snail. It employs a radula composed of a ribbon-like structure to which are fixed teeth. With this amazing organ it is able to drill through shell of the whelk like a flexible rasp.
Hold your whelk shell up to the light of the sun. If the radula of the predator has penetrated the whelk shell, you can rest assured that the whelk did not die of old age. But not all of these drilled holes completely penetrate the shell. The whelk successfully dislodged its attacker and lived to face another day. You are looking at battle scars - like those seen on an ancient suit of armor.
The Restless Nature of Beach Sand.
The beach is a delightful panorama; we are
overwhelmed with the immensity of space. But we are more intrigued with the
small changes that continually occur. It is this sense of stirring and
transition that draw us there again and again. Clouds pass serenely above the
rolling waves as sandpipers play tag with the wave fronts, while crabs scurry by
on import errands, and even the sand beneath our feet responds to wind and
wave. 
This movement of sand is the most difficult to perceive because it occurs so gradually, but it ultimately determines the character of the beach. The contour of the beach is changed by the coastal current, and the current in turn changes with the periodic accumulation of sand shoals in the delta of the Stono Inlet.
The beaches are all sustained from a huge offshore reservoir of sand on the continental shelf. The ancient deposits of sand that rest there were brought down from the Appalachian Mountains many years ago by the streams and rivers. Even at the edge of the continental shelf wave action is forever nudging grains of sand back up toward the land. In all this slow but inexorable process, there is a gentle winnowing and sieving so that the smaller grains are separated from the larger and selectively brought toward our beaches.
Even when the sand grain is carried by high tides to a distance well above normal wave action, its travels are not over. There the wind participates as it whiskbrooms the beach and remodels the dunes. You can sense the winnowing action of the wind if you lightly drag your feet over the dry sand of the upper beach. The loosely packed tiny grains emit a soft squeaking sound as they slide by one another beneath your feet. They are still in the process of moving elsewhere.
A number of years ago, I had driven the length of the beach in the town turtle-truck after dark to inspect lighting on the beach from homes and commercial buildings. Now returning home late that evening, I was carefully following my own tire tracks to lead me through the darkness to the Fiddler’s Run beach exit at the less populated eastern portion of the island.
Suddenly I encountered the long black line of a turtle crawl etched on the sand of the moonlit beach. Her track crossed over mine, so she even now must be on the upper beach. Turning off the lights and engine, I stepped from my twentieth century vehicle into a far more ancient world.
A quarter-moon high overhead faintly illuminated the broad surfaces of the beach and ocean but left the mass of Kiawah Island solidly black at that late hour. As I followed the wandering track up the beach, I first became aware of the turtle by the rustling sounds of sand being scuffed up and thrown about. Guided by those sounds, I soon made out her large dark shape.
Quiet
ly
approaching, I saw that the laying of eggs was complete; she was in the act of
covering and concealing the nest. All four flippers were flailing and sand was
flying everywhere as she turned this way and that to make it as difficult as
possible for the hungry raccoon or the sleepy turtle patrol to find that nest.
Departing, she made the 100-yard dash directly to the water's edge in 17 minutes
‑ pretty good time for a turtle.
As I watched her leave, with the black silhouette of our island behind me and the turtle disappearing in the breaking surf, the quarter-moon disappeared also behind a dark cloud. I felt transported back to the Mesozoic era ‑ an obvious impossibility because Homo sapiens has traveled less than a million years down that incredible passage of time, and Kiawah Island had yet to be built from sands yet to be brought down from mountains yet to be formed. But there were other beaches and early ancestors of this turtle were there, performing the same ritual, beneath the same moon for those millions and millions of years.
I tried to imagine the reptilian ancestor that first became a turtle by enclosing its soft body within an armored box from which only retractable legs and a bony head protruded. The fossil record speaks of multi-ton monsters such as Archelon, with a twelve-foot flipper spread, and Meiolania, with a horned skull two feet wide.
On that dark beach it was easy for me to imagine such a turtle coming out of the surf with that huge horned skull raised as it scanned the beach for danger and the fluorescent glow from attached marine organisms emphasizing its menacing bulk. That would be enough to send shivers of fright coursing up and down the spine of even the bravest. Hastening to the security of my own armored box on wheels, I found my beach exit and returned to the world now dominated by that soft-bodied mammal called Homo sapiens.
Nesting by Diamondback Terrapins
Loggerhead turtle patrol members will be especially interested in the nesting of the Diamondback terrapins that dwell in the marsh creeks. The story is quite similar to the one we are familiar with for the Loggerheads. Sparsely vegetated dunes and isolated marsh islands are favored as nesting sites. Females generally emerge at high tide beginning in May to dig a flask‑shaped nest with their hind legs. The average clutch contains eight pinkish‑white leathery eggs, which require about fifty-five days of incubation. Nest temperature during the middle trimester determines sex just as for marine turtles; warmer temperatures yield more females, cooler temperatures favor males.
The hatchlings, each just the size of a twenty-five cent piece, emerge from the security of the nest to enter a marsh bristling with hungry predators. This tiny terrapin hatchling, wandering off on its own, cannot locate the guideposts to successful living by trial and error. Its world is not forgiving – one error is all that is allotted to each hatchling. Does it have a built in guidance system just as we have found for its larger cousin, the marine turtle hatchling. Or does it already recognize in some innate way the distinct landmarks of its tidal creek – from which it will never stray?
The uncertainty of where the terrapins spend their early years resembles the mystery that surrounds the first years in the lives of marine turtles. The two and three year olds (less than 3 inches in length) are seldom found in the marsh. It is thought that they may conceal themselves in the piles of dead spartina grass at the marsh edge. The small grey terrapins would be perfectly camouflaged in the clumps of dead reeds in their mottled shades of gray.
The Leatherback
Occasionally the sea will
bring to our shore the carcass of a monstrous reptile, and you, seeing it there
in the surf, might think it had underdone a time warp and come from a steamy
inland sea that it shared with the dinosaurs and other ancient reptiles. You
would be correct, for its ancestors can be traced back to those prehistoric
times. This relic is the most massive of all living reptiles, has a 5 to 7
foot, tear-shaped body from which a relatively small head and four huge flippers
protrude, and the entire beast is covered wit
h
a black, leathery hide. It is Dermochelys coriacea, "the turtle covered in
leathery skin", the Leatherback.
It is set apart from the other marine turtles not only by it size and leathery skin but also by its wide range of occurrence. All marine turtles occur in tropic and semi-tropic waters but only the Leatherback ventures into the cold northern and southern oceans, and there are even reports of sightings of Leatherbacks swimming among the icebergs. Its nesting habits are more conventional, and for that purpose it uses beaches in the tropical zone.
The prowess of this turtle and the physiological adaptations that are being revealed by modern studies probably contributed in large measure to its durability down all those millions of years. Unfortunately it now appears dubious that the Leatherback, now classified as endangered, can continue to survive over the brief span of a few centuries that it has shared with modern man.
The Many Moods of the Maritime Forest.
Much of the aesthetic appeal
and charm of the Low Country derives from the moss‑draped live oaks along the
roadways and waterways. Live oaks, Spanish moss and the animals and birds
associated with them clearly belong together in the mosaic that defines this
land. They form a partnership. Each contributes its unique measure to the
final composition. The moss depe
nds
upon the tree for support but does it no harm. Small animals such as the anole
find both shelter and insects in the moss. The tiny chickadee often is seen
searching the gray streamers for strands to line its nest. And some of the
warblers carry this one step further and place their nests in dense clumps of
the moss.
On a pleasant day, when the moss and squirrels are fluffy and the tree trunks are a match in the warmer shades of gray, even the shadows blend into that monochromatic theme to create a placid, harmonious composition. But at other times, when moss, oak and squirrel are uniformly dark and sodden with rain, the mood changes dramatically. The lowering branches and dark shadows add to the threatening gloom; the approach of a headless horseman seems imminent and even lines of poetry by Edgar Allan Poe are brought to mind.
When summer squalls sweep through, the maritime forest gives the Low Country yet another look. The forest seems vibrantly alive and all is in motion, like the roiling surface of a mountain stream. The moss thrashes and tosses in rhythm with the tumultuous surges; stretching out to grasp each gust, then fluttering down to meet the lulls. But some storms are too violent, and Hurricane Hugo was much too vigorous for the fragile moss. One of the many disasters that distressed us all was its loss. Then, we really missed those intangible qualities that the moss had added and most of us had taken for granted. Today the moss has returned, and this has helped heal the wounds from that terrible storm.
Little Animals That Dwell in the Intertidal Zone.
To the casual beach stroller the intertidal zone of the beach appears to be a desolate place occupied by an occasional shorebird or a few tiny fish trapped in a tidal slough. Unending waves surge and rip currents push and tug. The temperature and salinity rise and fall like the waves. Certainly, this zone would appear like a ghetto for marine life. And yet, the zone is teaming with life.
This is largely a community of crustaceans, mollusks and worms that are collectively termed macrofauna, although they may seem micro‑ to us. They constitute an important link in the food chain. The little organisms consume the truly microflora and microfauna, the plankton, brought in by the sea, as well as the detritus that accumulates in this zone. The foods thus fixed at this first level are then passed on as essential foodstuffs for the larger invertebrates, near-shore fish and wading shorebirds that feed upon these macrofauna.
The coquina clam is one member of this community that may easily be found by the beach comber, for it is within the upper size range of 1/2‑3/4 inches. Its small wedge‑shaped shell is known for its subtle variations in pastel colors. These range from pure white to yellow, rose, lavender, pale blue and deep purple, interspersed with darker rays of color. If the coquina clams were larger, their shells would adorn the mantelpiece of every beachcomber on the island.
These clams are far from sedentary. Their survival in that turbulent, shifting beach zone depends upon their speed of digging down through the fluid sand. With each wash of surf, they are exposed. When the wave recedes each one rapidly thrusts its hatchet‑shaped foot down through the sand, expands the tip into an anchor and pulls itself downward. Within two or three such thrusts, it can pull itself beneath the surface. Then up go the siphon tubes and filter feeding is back in operation. They are no slouches even though they are clams!
They do all of this in unison with all their neighbors, so the collector will see hundreds of the colorful little clams all lurching down into the shifting sands like puppets on strings at the close of a marionette show.
Members of
the Turtle Patrol Must Be Good Trackers.
The Kiawah Island Loggerhead turtle nesting patrol depends entirely upon the track of the female turtle to inform them of the presence of a nest. And most volunteers soon acquire the additional skill of reading the nesting site in order to probe correctly for the nest.
If the nest had been raided prior to the arrival of the patrol, tracks of the culprit usually will reveal its identity. The patrol may find the tracks of a fox following up the larger track of the nesting turtle. So, the animals play the same tracking game. And sometimes the fox prints reveal the presence of one or more young kits following their mother and learning the basics for procuring a breakfast of turtle eggs.
At hatching time, the patrols must sort out the tiny tracks of the hatchlings as they made their way to the ocean and distinguish them from tracks of their predators, the Ghost crabs. When the two sets of tracks intersect, we know a small tragedy may have occurred. If the track ends at the mouth of a crab burrow, we know that one more hatchling must be crossed off our list of survivors.
Rookery Pond Revisited.
Within
recent times, only one swampy pond on Kiawah served as a nesting rookery for the
very selective herons and egrets that visit Kiawah Island. It is now just pond
#32 in the community association records, the pond that runs along Turtle Beach
Lane in the middle of the island. The Environmental Inventory of Kiawah Island
in its 1974‑75 survey of birds on Kiawah stated that the small pond, then c
alled
The Rookery, was the only site on Kiawah for breeding by wading birds. The
rookery was confined to a dense stand of low swamp willows that grew in the
midst of the tiny wetland.
According to my Field Notes, I first discovered or rather rediscovered The Rookery one morning early in May of 1979. This was before construction of the Turtle Point Golf Course was begun later in the same year. I can remember as though it was yesterday hearing a noisy commotion of birds ahead of me as I wandered through the woods on that morning. Leaving the shady shelter of the trees, I entered a sunny field that is now the 17th hole of the golf course. Pushing my way through the dense brush and over tangles of brambles and vines, I came upon the wetland completely overgrown with tall cattails - and there in the center were the swamp willows.
The low trees stood together in a tight green cluster with branches drooping in typical willow fashion, intertwining and reaching down to touch the surface of the shallow pool in which they grew. Overhead, herons and egrets were flying in and out of the swamp in large numbers, calling all the while. As I pressed further into the swamp for a closer look, I could see through the dense tangle of the willows two large alligators floating side by side in the water. I counted 27 flimsy nests of slender sticks precariously balanced on the branches above the patient alligators.
Transfixed, I continued to watch the bustling scene as herons and egrets continually arrived and departed with flailing wings and loud cries that announced their arrivals and departures in a medley of dialects. Common and Snowy egrets as well as Green herons were well represented, while three Anhingas soared overhead. However, it was not the best of places for an inexperienced naturalist to visit, and I unwisely lingered too long. As I staggered out, I found I was now bearing a heavy load of ticks, and later found to my distress that chiggers also had taken advantage of my innocence.
The Rookery
The herons and egrets are a gregarious bunch that prefer to nest together in noisy, crowded colonies called rookeries. They are like their human counterparts that also nest together and demand good home sites, police protection and availability of good shopping centers. So too, these birds are very selective in their choice of a rookery. There must be sufficient tree canopy to accommodate all the nests spaced just one beak-peck apart, there must be protection from the many predators eager to devour their precious eggs and chicks and there must be a plentiful supply of nutritious food close by to feed those ravenous youngsters.
Within recent times, only
one swampy pond on Kiawah seemed to meet all these requirements. It is now just
pond #32 in the community association records, the pond that runs beside Turtle
Beach Lane in the middle of the island. A tight little set of ecological
relationships made this rookery possible. The cattails and water‑loving swamp
willows had filled the wetland. The wading birds were attracted to the secluded
site by the plentiful fish, snakes and frogs; they stayed to nest because the
low willows provided a secure nesting site.
The site was secure because the water beneath the trees dissuaded the usual nest predators such as bobcats, raccoons, and snakes, and the alligators ensured that they would keep their distance. In compensation, the alligators consumed the chicks that fell from the nests, but then, those unfortunate chicks were doomed in any event.
So, this delicate balance of wildlife and habitat had remained intact for decades and possibly centuries. Following construction of the Turtle Point Golf Course, the luxuriant plant-life of the wetland remained undisturbed. Birds continued to forage there for food, but they no longer found it suitable for nesting.
The next major change was wrought by hurricane Hugo in 1989, as it yanked up most of the weakly rooted willows. Thereafter, the developer made the decision to convert the swamp into another pond; all vegetation was removed and the pond was dredged to its present depth. Now, it is one more attractive pond on the island, but the herons and egrets must travel elsewhere to rear their chicks.
In Spring Thoughts of Alligators Turn to the Opposite Sex.
In spring, the thoughts of a male alligator turn to the opposite sex, and he may roam far and wide in search of a mate. In the process, he may inadvertently end up in someone’s garage or swimming pool to the consternation of all concerned. Courtship is long and elaborate, and bellowing is an important component. Bellowing usually occurs in the early morning, and it serves to attract both sexes to a pond where there might be a potential mate.
Only males were thought to bellow, but now it is known that females bellow a different tune to attract courting males. She may be quite successful at this and attract a number of males. Usually the largest male will aggressively drive the other males from the pond before approaching the female.
Courtship begins in a leisurely fashion as the male and female touch snouts rub heads and emit coughing sounds. The male can be surprisingly gentle with the female at this time. The pair may circle one another, press close together, part, intertwine, submerge and blow bubbles. This may go on for quite some time with pauses while they float quietly as though studying each other. Sometime during this process, mating occurs - often beneath the water.
Combat!
I was biking along the path beside Governor's Drive one day in the vicinity of Egret pond, when I encountered two lizards locked in combat beside the path. They were Broadhead skinks, the largest lizard in the state and fairly common on Kiawah. The male has a broad head with eyes so dark and recessed that they appear to have been burned into the skull, and during the breeding season the skin over the head turns an orange-red.
The two males, each about one foot in length were locked in combat over the usual things males fight about. Facing one another, each had a firm grip on the shoulder of the other, but their jaws were not powerful enough to pierce the scaly skin of the opponent. Driving against the other, they swirled around like a flaming pinwheel with the long tails streaming out on the perimeter.
At other times the gyration ceased, and as they pressed against each other their efforts were reflected in the tremors of their bodies. Finally, one did prevail, grasped the head of the other in its jaws and threw its body over its opponent. Either the loser relaxed or the victor slackened its grip, and the two separated. The victor remained in place; the loser ran to the middle of the road where it sank down in a sunny spot on the yellow stripe.
Only now did the victor become aware of the wheel of my bike just a foot away and my body looming above. It froze in apprehension as though trying to readjust its moment of triumph to one of terror. And I for the first time had to assess my role in the matter. Should I just pedal off, or should I play the role of God and influence the outcome?
I chose
the latter role on the basis that humans had built the road and the vehicle that
might at that moment be approaching to crush the exhausted loser. Backing off
slowly, I left the victor to savor victory; riding toward the loser, I
frightened it into the parking on the opposite side of the road. I knew that
nothing thing else I might encounter on my ride would match the ferocity of that
battle.
Territorial Behavior of the Carolina Anole.
Probably the most beautiful and certainly the most common of the six kinds of lizards that live on Kiawah Island, is the Carolina anole (Anolis carolinensis).
These little emerald-green lizards that scurry about almost beneath our feet are fascinating as well as beneficial members of our community. The male is highly territorial and spends much of its time defending a few square yards of space from encroachment by other males. He may not know initially whether the intruder is another male or a female, but he will make that determination with an intricate series of moves.
First he puts on his most intense green hue and compresses his body. Then he flares his brilliant red throat fan, and a black patch becomes prominent behind each eye. He bobs his body up and down as though doing a reptilian version of push-ups on his short legs; and all the while, he watches the other anole closely.
If the intruder does not flee, he advances a few steps and repeats the signals. This ritual is understood perfectly by the other males; it means keep your distance, this spot is taken.
At some critical distance, the interloper has no further opportunity to flee, and the male races toward his enemy with mouth wide open. A battle may ensue, the smaller of the two may be thrown over on his back, but usually no harm is done before the loser hastily retreats.
If the encounter is with one of the females, his aggressive bluster quickly turns into courtship. He performs what appears to be the same ritual of color changes and push-ups. Through it all, the female remains motionless and observes her suitor closely. The details of this ritual are different for each species, and soon she knows whether her suitor is acceptable. The female must be greatly moved by the performance, for it has been determined that she cannot develop an egg without this exciting display to release the proper hormones.
However, the female doesn’t show much commitment to motherhood. She will drop the fertilized egg wherever she happens to be when the impulse moves her. This may be into any shallow depression in moist soil, leaf mold, rotten wood or a tree cavity. If nothing gobbles it up in the next few weeks, the soft-shelled egg hatches to release a two inch long replica of the adult. Like the turtle hatchlings that depart from our beach each summer, the juvenile anoles enter a dangerous world, and they too instinctively begin life entirely on their own.
Osprey – Owl
Nesting: Part IV.
By the end of the month
following the loss of the three osprey chicks, the deserted nest began to look
strangely shabby. It seems that ospreys don't just build a nest at the
beginning of the season and then use it rent-free. No, maintenance and
restoration must go on all through the season. I first realized this while I
was observing the same nest earlier on a happier day when chicks were present.
One of the parents several times brought small branches to the nest. She proceeded to work the branches into the nest with much rearranging. The inquisitive chicks showed a great interest in the procedure, and I suspect the parents had a second reason for this performance. This must be their only opportunity to teach the chicks the essential skill of nest building.
What of the other nest, the one built by the inexperienced pair of ospreys as related in Part II? By the time the female settled down over eggs, the nest had assumed a presentable appearance. It was located lower than the first, in the middle of a living pine tree. Would it be better protected from those ravenous owls?
The family looked fine; the two chicks were about half grown and well feathered in the plumage of the juvenile stage. On their backs the speckled tan and dark brown mixture matched amazingly well the pattern and colors of a pine cone beside them in the nest. I wonder whether this is coincidental or another example of nature's camouflage for a species that so frequently nests in pine trees?
One parent stationed on a branch above the nest as well as the chicks in the nest continually scanned the sky and tracked each passing bird. Sometimes I could tell that they were watching one so high that it was beyond my range of vision. When a Red-tail hawk passed in the vicinity of the nest the parent dropped to the nest rim while calling loudly, and the two chicks crouched in the bottom of the nest. It became apparent to me that this family was vigilant for any threat, and I was increasingly optimistic for their success.
When both chicks fledged later
in the spring, I knew that we had a successful nesting despite the owls. It
would be only speculative to seek the reason for the success. It might have
been the safer nest location, more vigilance by the ospreys or simply that the
owl family had grown tired of osprey squabs.
Osprey – Owl Nesting: Part III.
In the earlier story, I asked you a rhetorical question as to whether owls and ospreys could be good neighbors. From subsequent observations, the answer is emphatically NO.
You may recall that a pair of Great Horned owls nested in the old osprey nest near Willet Pond. The nest was high in a dead pine snag on the isolated little island across Bass creek. At that time the island was heavily wooded with tall pines and dense underbrush of myrtles and low saw-tooth palmettos. An ideal nesting site for any animal that wished to be left alone.
When the two fluffy brown chicks were half-grown, they both disappeared from the nest overnight, and I assumed that they had fluttered down on stubby wings to the undergrowth. It had happened the year before, and I had located the chicks as related in another story. This odd behavior of the owls has frequently been reported. It may be an acquired trait that removes the chicks from the exposed nest as soon as possible.
The owl family probably will remain on the little island all through the spring. It is known that the parents customarily continue to feed the chicks into early summer and well past the time they are capable of flight. To the busy owl parents, plump osprey chicks in exposed nests high on nearby pine snags must present tempting targets.
This brings us to the osprey nestings, of course. As I mentioned in the earlier story, two osprey nests were established within a quarter of a mile of the owl nest. The first nest with chicks present was the one furthest from the owls. I became aware of the three fluffy gray chicks when I spotted their bobbing little heads over the rim of the nest as the parent fed them.
Only a week later just one chick could be seen. It crouched close by the parent who was perched on the rim. When I checked two days later, the nest was empty, and one osprey parent was perched in a spindly pine tree several hundred feet away. Apparently the owls had taken them all.
Osprey ‑ Owl Nesting: Part II.
To my astonishment, the Great Horned owl family in the nest near Willet Pond survived a cold, driving rainstorm that descended upon us from the northlands and raged for a long day and a night. Shortly after the storm passed, the nest appeared empty, but that was because the two owlets were huddled down so deeply. The next day they were both up and stomping around in the nest as though impatient for mommy to arrive with breakfast.
All seems harmonious between the owl and osprey nests. Indeed, a second pair of ospreys is building a new nest even nearer the owl nest. This pair obviously is inexperienced. The nest looks like a small haystack had been whirled up by a tornado and deposited in the tree. Even as I watched, the male alighted on the back of the female in the nest shambles and looked all about for the longest time as though thinking, "Ok, I got up here, now what am I supposed to do?"
Let’s hope he gets it right and all that furious assembly of twigs was not in vain.
How the owl family will react to all this foolishness by those flighty ospreys remains to be seen.
One winter I observed a pair of Great Horned owls nesting in an old osprey nest on the little island across Bass creek from Willet pond. With a spotting scope, I could make out the head of the sitting female, and especially as she turned her head to scan for intruders, I was able to see the two tufts of feathers jutting up like ears. She was on eggs at this time, for their nesting season comes early in the year.
Several weeks later the owls had hatchlings in the nest. I first suspected this when I noted the female setting considerably higher in the nest. I was certain of the hatching on the next day. Viewing the nest through the spotting scope, I made out a large dark object blowing up and down in the wind, but I could not identify it. It looked like a wing, but surely the owl was not sharing her nest with another bird!
Then the owl began to feed the newly hatched young and the black object was no longer to be seen. I must conclude that she had caught a large black bird – probably a crow – and brought it back to the nest.
Activity at the owl nest was not the only excitement, because a pair of ospreys had set up housekeeping in a second old nest. The second nest was about one quarter of a mile away and clearly visible from the first. This may present a problem; for it is well known that Great Horned owls do not tolerate nests of other raptors anywhere near their own nest.
How this drama will play out
remains to be seen, but I promise to reveal each installment right up to the
final denouement.
Kiawah Swamp Garden.
Kiawah Swamp Garden, located at the end of Turtle Beach Lane, is a tiny remnant of a freshwater wetland. The little pond was dumped upon, neglected and vilified while all the surrounding land underwent profound changes into golf course fairway and beachfront home sites.
It managed
to maintain its integrity and its continued isolation because of the presence of
a dike that separates it from the larger pond that is beside Turtle Beach Lane.
The dike that separated the two ponds in earlier times had constituted a pathway
to the beach through the extensive wetland that formerly ran all along a chain
of ponds.
The perplexing question was what to do with the tiny pond. Some of us felt that it should be preserved as a microhabitat representative of the original freshwater swamps that had existed on the island prior to development. A path of bark mulch was placed upon the ancient dike and extended through the low ground around the pond. For completion, a little wooden bridge spanned the wetter portion of the little garden.
Natural vegetation was encouraged and supplemented with other plants characteristic of such a freshwater wetland. As the character of the natural habitat began to return, the native animal and bird life came back of their own accord. These included the Boat-tailed grackles and Red‑winged blackbirds that sing and nest in the reeds, the alligators, turtles and snakes that sun on the half submerged trees, and the wading birds ‑ the herons and egrets ‑ that enjoy the plentiful food in that secluded setting. Some of these are usually out on display. Come visit it!
Anhingas Are Great Sunbathers
The huge aquatic bird called the anhinga will eat about anything it can capture in a Kiawah pond. However, fish are its primary prey. As it hunts beneath the surface, its narrow beak that terminates in a sharp point serves as an efficient harpoon. This weapon is rendered even more formidable by cocking the head back as the neck is folded against its shoulders. Driven by powerful legs and webbed feet, it becomes a streamlined dart. As it approaches a fish, the head and neck suddenly thrust forward to impale the luckless fish upon that sharp beak. Then up it comes to the surface, and with a deft shake of head and bill, it dislodges the fish, tosses it into the air and catches it head first for a quick swallow.
Once it has caught its fill, the anhinga has one more task, that of drying its sodden plumage. Emerging from the water by a slight flutter-hop, it rests on a low snag to engage in “sun-bathing”. Birds that both fly through the air and swim through the water have a special problem with weight. Ideally, they should be both buoyant in air and dense in water. This seemingly contradictory requirement is resolved in most aquatic birds by adjustment of the amount of air entrapped beneath the feathers and within the body.
The anhinga has solved this problem in a different fashion; it grows feathers that absorb water. The wet feathers no longer retain air, buoyancy is lost and the bird can easily remain submerged. There is a cost for this however, for the bird ends up with all those soggy feathers when it attempts to fly. Also there is a loss of the excellent insulation normally provided by dry feathers. For these reasons you will often see the anhinga orient itself with wings spread wide and with its back to the sun. It “hangs itself out to dry” and at the same time receives maximum absorption of the sun’s rays for warmth.
We know very little about the activities of most of the mammals on Kiawah because they are nocturnal and thus concealed from our sight. Therefore, we must depend upon their tracks to tell us where they roamed and what they did during the night. In the interior of the island, this is difficult to do, because leaves often cover the tracks.
One way of overcoming this difficulty is to create track plots by clearing and smoothing a small patch of ground where the passage of animals is suspected. The prepared area may be lightly dusted with powdered lime to enhance the pattern of tracks.
Another
way of determining the presence of animals is to attract animals to the prepared
area, and scent is customarily used as the attractant. A small disc of a
volatile, odoriferous compound highly attractive to most carnivorous animals is
placed in the center of the plot. Not too surprising, such a plot is called a
scent station. The next morning, tracks of the nocturnal visitors should be
clear for identification.
Marks from the cloven hooves of
the deer are the easiest to identify, but the nearly human handprints of the
raccoon are quickly learned too. The round paw prints of the fox and bobcat are
more difficult, and inspection for claw marks becomes critical for the
discerning sleuth. Beyond that, tracks of birds, snakes, alligators and
possibly even the legendary cougar add their challenges.
Rhythms of the Tidalmarsh
It is worth emphasizing tidal in tidalmarsh for the existence of the marsh and the behavior of all plant and animal life that exists there must adjust to the daily rhythm of the tides. Animals that live on the marsh or come to it for food and shelter must conform to the tidal rhythm.
As the tide rises, animals such
as the raccoons, field mice and cotton rats retreat to high ground. The
periwinkle snails that have been grazing on the algae that cover the mud climb
stalks of spartina to avoid the water and the predators that come in with the
rising water. Those that enter with the tide include the mud crabs and blue
crabs to scav
enge
the organisms that did not escape the rising water.
Other rhythms, also determined by solar movements, proceed more slowly. I refer to the seasonal changes as planet earth wobbles in its orbit around the sun. With the shorter days of fall, creek fauna decline both in total numbers and species diversity. Organisms that developed and grew during spring and summer now have matured sufficiently to leave the shelter of the marsh. Even some of the permanent residents retreat temporarily to deeper and warmer waters in the estuary during severe winter weather.
Like the endless cycle of the tides, creatures of the marsh ebb and flow with the seasons. So too, does the marsh grass, for the spartina stalks darken and die to add to the mulch that will be needed in the coming spring. But even as they die back, sprouts of new growth rise from the perennial roots to create the marsh of the coming year.
The Crab That Is Uncertain Whether It Is an Animal of the Land or the Sea
Both Ghost crabs and Loggerhead turtles are ambivalent; they are wedded neither to the land nor the sea. The one is an oceanic creature that has chosen to spend its adult life ashore; the other is a creature of the land that has chosen to spend its adult life at sea. Just as each female turtle returns to the land to deposit her eggs, so too does the female crab enter the sea briefly to liberate her eggs.
She has incubated and aerated the mass of eggs within her abdominal flap. When the eggs have developed to the larval swimming stage, she enters the surf to release them. She ruptures the membrane of each egg by vigorously swirling the egg mass, and the tiny larval crabs are released to join the floating plankton community.
Now, the microscopic organism recapitulates all the drama of its evolutionary history; the migration of a creature of the sea to an existence on an alien shore. As the newly hatched larval form drifts in the currents of the sea, it sheds its cuticle several times to accommodate its increasing size and shape. Finally, it reaches the last larval stage called the megalops, and this tiny creature, alone in the sea, now must obey whatever instinct drives it shoreward.
The long process of evolution has designed the megalops stage to cope with this difficult landing. The cuticle is thick and heavy, and the body rounded. The appendages are grooved and sculptured so that they fold tightly against the body, each fitting snugly to the next. In the hazardous act of coming ashore in the shape of a small marble, these structural adaptations protect the megalops against the battering of surf and sand.
Once on the beach, the tiny creature digs its first burrow, just a small hole in the sand. Here it will undergo the final molt that will transform it into the shape of a miniature Ghost crab. From that time on, the life of the young crab is a gradual progression up the beach. At first, it digs its burrow in wet sand that will be covered by the rising tide. At this time in its life, it needs more frequent wetting of the gills and is more susceptible to drying. Therefore, it has need of moist sand at all times. When perhaps half grown, it digs above the high-tide line; when fully adult, it goes well up into the upper beach or even among the dunes, attaining there the farthest point of the its land-ward migration.
Biologists employ the term “ecotone” to refer to any border between two habitats such as the edge between a woods and a fairway or a pond. Every birder soon learns that the way to see a large variety of birds in a short time is to plan field trips that include various ecotones. The reason is that birds commonly require more things for survival than can be had from a single habitat such as a dense woods or an open field. If their needs can be met by using both habitats, their chances for survival are increased. And that's where they’ll be, at the border. The field may provide insects or seeds for food and grass for lining nests; the woods may have twigs for the nest and protective cover from enemies.
These ecotones also benefit animals such as deer, foxes, raccoons and squirrels. In fact, these animals are termed "edge" species because they occur most frequently at edges or borders between different types of habitat. They use these ecotones as corridors as they move about to secure food and water.
The term "greenways" is the buzzword in vogue these days for the corridors that wildlife must use as they seek food, water and other essentials for life. Fortunately, these greenways are still plentiful on Kiawah. To ensure that these corridors remain open in the future, it will be important to retain generous setbacks behind homes on golf course fairways, marsh perimeters and pond edges. Preservation of these greenways is an important contribution that both the developer and the property owner can make for the welfare of wildlife on the island.
On Kiawah, we have "brownways" in addition to greenways. I refer to the immense dunes that many of the birds, mammals and reptiles use for various purposes. Some use them primarily as corridors on their travels about the island; others such as the deer seek the myrtle and holly thickets as shelter during the daytime; still others make the dunes their permanent home.
For simplicity, we artificially divide the island up into these separate “habitats”. In reality, all are interconnected, all are fragile and all are essential for the preservation of the totality of our wildlife communities in a balanced and wholesome state.