A Natural History

Every child should have someplace wild nearby. For me it was the Rockefeller State Park Preserve. I was fortunate enough to have the entire sprawling forest right behind my house, accessible through the back fence. So much of my childhood is connected with that place. I remember searching for ghosts with a polaroid camera, playing make-believe with the neighbors, and taking a winter walk with my family. When it snowed we would sled down the hill behind our house (and my unfortunate brother split his lip this way, when his sled collided with a tree).

I really came to cherish the forest when we got a dog. Dogs need to be walked, of course, and the forest was the perfect place to do it. Most dogs would love to be walked somewhere with so many plants, animals, and other dogs. But my dog was rather special. She was only mildly interested in chasing squirrels; she was even apathetic towards other dogs. There were really only two things that mattered to her: humans and food. The forest had the former in abundance—people out for a walk or a jog—and every time I passed another person I had to wrap the leash around my wrist and hold it tight to prevent her from jumping all over her new friends. The forest also had things to eat, in the form of dog and deer droppings; but I tried to discourage that, too. 

My dog’s life came and went, but the forest remained. The many years of walking her instilled the habit in me so deeply that I continued to take walks in the forest just for myself. In fact, I started to walk much further than I ever could with my poor girl, since she had hip dysplasia (a common malady among purebreds). The forest was bigger than I had ever known. There were so many paths left to explore, stretching for miles and miles behind my house. It has been the work of years to know them all; and even now I am missing a few corners of the map. The park is so big that I reached its most distant corners when I took up running as regular exercise. That is the only way (besides horseback) to go from one end of the park to the other in a comfortable span of time. (Cycling is not permitted in the park, though it is allowed on the Aqueduct Trail.)

In this post, then, I would like to tell you everything I have learned about this park over the years. I have done my best to be as thorough as possible, describing the geography, climate, topography, history, flora, and fauna of the park. But I am not a scientist or a naturalist, or even a particularly knowledgeable amateur. Indeed, this post would have been impossible without the resources compiled by experts and nature-lovers alike, many of which are free online. Technology, for all of its ravages, does have its perks.

We shall begin at the beginning: with the formation of the earth. According to the geological maps I have been able to find—available on a superb application called Rockd—the bedrock of this area is composed of Fordham gneiss. The gneiss was formed between four billion and one billion years ago, which makes it one of the oldest rock formations in the world. Gneiss is a metamorphic rock (made by transforming other types of rock, such as granite in this case) created under high pressure and temperatures. This gives it a characteristic and rather attractive banding pattern that you can find on some of the exposed boulders in the area.

According to what I have been able to find (and the American Museum of Natural History’s exhibition on the New York State environment is the best resource I have come across), gneiss tends to form only a thin layer of fertile humus on the surface, making such areas ill-suited for agriculture. Further, gneiss tends to weather into “massive rough surfaces” (to quote the AMHN), which again is not ideal for planting and harvesting. You can see some of the exposed gneiss at various points in the park, most notably in the high elevations between the Aqueduct Trail and the Big Tree Trail. I suppose that this gneissic bedrock is why the land was mostly left alone by previous farmers. (Admittedly, the Stone Barns Center for Food and Agriculture is situated on the same bedrock, and they seem to have no trouble with their agriculture.) 

The landscape also bears the traces of the previous ice age, which ended around 12,000 years ago. This is most obvious in the glacial erratics (large boulders left by the receding glaciers) that are scattered about. One of these is Spook Rock, a fairly nondescript rock with an obscure scary story attached to it, after which a trail is named. Then there is the nameless glacial erratic, which is tucked into a detour off of Nature’s Way, one of the park’s smallest trails. According to a story in the New York Times from 1987, this massive rock is perhaps the biggest glacial erratic in the country, and certainly the biggest in the Hudson Valley. It stands about 20 feet high and is over 60 feet in diameter, which means that it must weigh several tons. Just imagine such a thing being budged, bit by bit, by frozen water. Nowadays, benches are set up around the rock, where I assume educators give presentations to students. 

On the subject of rocks, I ought to mention Raven’s Rock. This is not a glacial erratic, but a large exposed rock formation. As usual in these parts, a couple ghost stories have been attached to this place, too. In fact, Raven’s Rock is referenced in Washington Irving’s The Legend of Sleepy Hollow: “Some mention was made also of the woman in white, that haunted the dark glen at Raven Rock, and was often heard to shriek on winter nights before a storm, having perished there in the snow.” Of course, there is some question as to whether the rock was named after this episode in the story, or vice versa.

The topography of the park is not especially dynamic. New York in general is geologically inactive. A mild earthquake in 2011 was enough to send people running from tall buildings, and made front-page news. A lack of tectonic activity makes for relatively flat landscapes, and consequently this area is hilly rather than mountainous. Rockefeller’s own house, Kykuit, occupies the highest point in the Pocantico Hills, just 500 feet above sea level. According to my running app, even the hilliest paths barely exceed 500 feet in elevation over several miles of trail. As discussed below, the paths were originally laid out for horse-drawn carriages, which require a relatively flat surface. 

The Rockefeller State Park Preserve partakes in the climate of the lower Hudson River Valley, which is classified as humid continental. This means that there are quite dramatic seasonal changes in temperature, from well below freezing in winter to upwards of 90°F (or 32°C) in summer—both of which can be uncomfortable and even dangerous if you do not take proper precautions. Rainfall is heavy and steady. The yearly average is over 50 inches (or 130 cm) per year—for comparison, London gets less than half that amount—and it rains in all seasons. The typical Hudson Valley sky is low and grey, a consequence of the ever-present stratus clouds. 

Even when it is not rainy, humidity is typically quite high, which can make summer days unpleasant. Even so, summer is my favorite time in the park, since the leaves shine with an intense greenness that I rarely see in Europe. It usually snows in the winter months, though how often and how much can vary quite a lot from year to year. The park can take on an ethereal beauty after a good snowfall. All of this snow, rain, cloudiness, and humidity can be somewhat depressing; but it does allow for a verdant landscape, full of plants and all the animals that they support. Fall is perhaps the most comfortable and certainly the most beautiful season in the park, when the trees turn bright shades of red, orange, and yellow. This effect is far more pronounced in the United States than in Western Europe, which is due to the much greater variety of tree species in America (a byproduct of the ice age). 

The Hudson River is the most important geographic feature in the area. The river is unusual for having waters that alternately flow north and south, depending on the ocean’s tide. This alternating current is due to the river being, in its southern portion, a tidal estuary, intimately connected with New York’s harbor. For this same reason, the Hudson’s waters are brackish (a mixture of salt and fresh water), are thus not potable. The Hudson also marks a divide in the area’s geography, as the rock formations on either side of the river are vastly different in age and type. The rocks directly across from the Rockefeller State Park, in Nyack, were formed in the Late Triassic, and have been found to contain dinosaur fossils. That is a difference of at least half a billion years in age. 

But the Hudson is not the only relevant water feature in the park. Several smaller rivers and brooks—tributaries of the Hudson—wind their way through the park’s confines, having long ago carved out a channel within the topography. The most important of these is the Pocantico River (whose name is derived from its indigenous appellation). It is normally between ten and twenty feet across, and usually not much deeper than your knee. Normally the current is gentle enough to allow you or your dog to walk right in, though strong rains cause the river to swell and flood, washing over the bases of neighboring trees. Even smaller and gentler are the little Rockefeller and Gory Brooks, which connect with the Pocantico and which all eventually flow into the Hudson. As charming as are these little rivers, it is worth noting that they are quite contaminated—more so, in fact, than the Hudson River itself—and this from sewage leakage. Do not be tempted if you are thirsty.

The biggest water feature in the park is Swan Lake, with an area of 24 acres. This is one of the most picturesque areas in the park, as well as one of the best spots to see many of the local bird species. Quite nearby, though technically not within the park itself, is Pocantico Lake. This lake used to be used as a reservoir, and ruins of the old waterworks building still stand next to the dam. Every year, the lake is stocked with hundreds of brown trout, which swim down the Pocantico River into the Hudson. Other native fish include perch and suckers; and if you have the relevant license you are free to cast your line into the waters—though I do not think I have ever actually seen somebody do so. (Judging from observation, the fishing seems to be better in the nearby Tarrytown Lakes.)

Human habitation in this area goes back far before Henry Hudson sailed up his eponymous river in 1609. Back then, the land of the park was occupied by the Wecquaesgeek people, a subgroup of the Wappinger. They spoke an Algonquin language closely related to the Lenape (the people who were living on the island of Manhattan), and lived as hunter-gatherers, dressing themselves in the skins of deer and beaver. When the Dutch began to settle in large numbers, in 1624, thus commenced a series of treaties, epidemics, and battles, all of which resulted in the Wecquaesgeek being pushed off their land. I do not know if any native artifacts have ever been found on the grounds of the park, or if anyone has ever looked. 

Nowadays, the only things that may vaguely remind the visitor of this history are the lean-tos, situated in the forest near Spook Rock. Technically, they are not lean-tos, but “survival shelters,” made by leaning sticks against the base of a tree; and I very much doubt that they actually resemble anything that was built by the Wecquaesgeek. I believe they are made as demonstrations for boy scouts, judging by the little benches that have been set up nearby. If you find yourself lost in the middle of the woods for an extended period of time, I suppose that knowing how to build one of these may come in handy. Perhaps the very oldest surviving human constructions in the park are the stone walls that can be seen in many areas. These were built well over a century ago by yankee farmers, and they accomplished several purposes. The fields had to be cleared of stones to allow for planting; and the stone barriers helped to mark boundaries and keep livestock from escaping. 

The history of the park as it exists today begins with one of the most controversial men in American history: John D. Rockefeller, Sr., a man whose very name has become synonymous with wealth. In 1893, Rockefeller purchased the land for what was to become his new home, Kykuit, on the Pocantico hills overlooking the Hudson. Part of the reason he chose this spot was because his brother, William, had already built a mansion for himself fairly closeby, called Rockwood.

Rockefeller was a man of few pleasures, among which was to ride in his elaborate horse-drawn carriages. Thus, he made sure to buy up huge tracts of lands adjacent to his new home, which he turned into a kind of paradise for scenic rides. This explains the peculiar characteristic of the park’s trails: they are quite wide and usually have a gentle inclination—both of which are necessary for horse-drawn carriages. Rockefeller was something of an amateur landscape designer, and many of the trails were laid out by the tycoon himself, along with his son. You can still occasionally see carriages being driven along the trails of the park, presumably owned by the descendents of the Rockefeller family, who still live closeby. (One friend of mine claims to have seen Martha Stewart riding around.) Another reminder of the continuing Rockefeller influence are the helicopters that sometimes fly overhead, presumably ferrying scions of this noble family over their domains. 

In the 1980s, this enormous swath of land—almost 1,800 acres of land (over twice as large as Central Park), with over 50 miles of trails—was donated to New York to be used as a park and nature preserve. Nowadays it is overseen by the state of New York, which maintains a visitor center off of Route 117. Here you can park your car, see a bit of art in a small gallery, take a map, use the bathroom, and learn about the wildlife.

When I was younger, as I walked alone through the tall woods, I imagined that the park was as close to pure nature as I was likely to see. But of course this is not true: the park is a managed environment, even if that land management is done with a light touch.

The most obvious human intervention are the trails. Topped with crushed rock, they are quite wide, smooth, and easy to walk on. The trails are carefully maintained. At some points in the park, stone retaining walls prevent a neighboring hill from spilling onto the trails. More subtle is the drainage system, visible as a series of ditches and gutters running besides the paths, which work to redirect rainwater away from the trails. Without simple systems such as this, I am sure that the trails would be washed away in a short while.

The park staff also work to control certain types of invasive species. One of these is a vine called mile-a-minute (Persicaria pertofoliata), so named because of its rapid growth rate—about six inches a day. This plant is indigenous to India, and its accidental introduction to NY has put native species in jeopardy, since the thorny plant grows so fast that it can literally smother its competition. The park staff is currently engaged in a battle to stop this vine from spreading, and is asking for volunteers to help in the fight. (If you would like to help, call 914-631-3064.)

Another obvious human intervention are the many areas of the park which are kept as grassland rather than forest. The staff maintain this area in several ways. The grass is cut down at the end of spring with a tractor and gathered into bundles, to be given to livestock. The staff also bring in livestock—goats, sheep, and cows, guarded by a few wary dogs—to graze the land in summertime. Personally I find it quite charming to come across a group of these farm animals on a walk. And the animals are certainly effective. They eat all day from dawn to dusk, and they leave hardly a stalk untouched.

In layout, the park is massive and sprawling. The furthest reaches of the park are bounded by the Hudson River to the west and the Saw Mill River Parkway to the East. But between these two boundaries the park’s extent is uneven. Bits of the park jut out past Route 117 to the north or Route 9 to the West. One major artery through the park is the Old Croton Aqueduct trail, which runs parallel to Route 9 and across it into William Rockefeller’s old estate. Another major division is Bedford road, which cuts the park into two fairly distinct areas: the part to the east of Bedford road tends to have fewer visitors than the part to the west.

Virtually every one of the park’s dozens of trails has its own personality. I am biased, of course, but for me the area closest to my house (between the Sleepy Hollow Cemetery and Sleepy Hollow Road) is easily one of the most beautiful sections of the park. There are three stone bridges that span the Pocantico River. These are the clearest signatures of the Rockefeller family: for the bridges would certainly have been costly to build, and they perfectly evoke the kind of European antiquity that the Rockefellers enjoyed. For my part, I think they are lovely constructions, totally in keeping with the primeval aesthetic of the park. When I was a child, I could not help but imagine legions of centurions marching over these apparently ancient viaducts.

Some of the most beautiful trails—especially in summer—are in the area surrounding the Stone Barns Center for Food and Agriculture. (Stone Barns is a non-profit, sustainable farm founded by David Rockefeller.) Here the forest gives way to rolling hills shaded by rows of oaks, and the stone buildings and fields of crops create a bucolic picture. Just as lovely is Rockwood, located right on the Hudson River. There, several paths leads up a hill to what appears, superficially, to be a kind of stone fortress overlooking the river. This is actually the foundation for William Rockefeller’s mansion, long since demolished. Here you can sit on the wall and contemplate the new Tappan Zee bridge, and even spot Manhattan in the far distance. (For some reason, flies love to buzz around these rocky walls in summer.)

One of my favorite places to run is the Thirteen Bridges Trail, so named for the many little bridges that lead the wanderer criss-crossing over Gory Brook. Once you finish this loop, you can cross back over Route 117 on one of the two metal bridges. Turning in one direction takes you on the Pocantico River Trail, which (you will be surprised to learn) runs parallel to the Pocantico River. Turning the other way can bring you to the Big Tree Trail. This trail runs along a lower-lying part of the park, and is noted (as you may have guessed) for its large trees. If you walk along the trail on a quiet afternoon, as the sunlight drifts through the canopy, and the sounds of birdsong echo from above, the enormous columns of trees can create the impression of being in a natural cathedral. 

This brings me to the flora of the park. By my count, the park is home to well over fifty species of tree. The tallest to be found is the tulip tree, which is so named because of its yellow spring flowers. The trunk is as straight as an arrow, and the tree can grow upwards of 150 feet (or 45 meters). In general, the tallest trees are found in lower-lying areas, often near the river. Erosion causes soil to fall from the higher areas and accumulate here. Apart from the tulip tree, the park contains a mixture of beech, maple, and oak, along with shrubbier trees such as sassafras and witch hazel. There are relatively few conifers—mostly spruces—and they seem to prefer the areas close to the rivers. The park also has some non-indigenous species, too, such as the beautiful European beech—with red leaves—overlooking Canter Alley. My favorite may be the (non-native) Shagbark Hickory on Douglas Hill Loup. 

In the fall, most trees lose their leaves. They accumulate on the ground as a thick, brownish, rust-colored matting. Even by late summer, this bed of dead leaves is still noticeable everywhere. It seems that all of the insects, fungi, and bacteria present in the park’s soil have their hands full with such a superabundance of nutrients; but sooner or later, the dead leaves decompose and enrich the soil. We must pause here to acknowledge the kings of the park, and indeed of all life: bacteria. They are the most abundant organisms in the park and absolutely essential to each vital process. This is most obvious with the case of diazotrophs, which are the bacteria that convert nitrogen gas into a form (ammonia) that plants can use. Without these helpful microorganisms, plants could not grow, and the rest of us would be out of luck, too. 

When it comes to shrubs, ferns, grasses, vines, and other sorts of plants, the species-count goes up into the hundreds. I could not hope to identify even a significant chunk of these plants. Using the application Plantsnap, however, I have collected a list of some of the more common vegetation. Claytosmunda (or interrupted fern) is intermixed with sensitive fern and spikenard, forming a thick underbrush of low, leafy plants in summer. In some areas there are thick masses of wild blackberry bushes, whose fruits are delicious and safe to eat, but whose vines are covered with painful spikes. In the more open grasslands one can find reeds and grass, as well as wild carrot.

(The application, iNaturalist, allows visitors to log any sightings of a species—be it bird, bush, or bear—within the park. This list, available here, has been a great aide to me.)

The most hazardous plant is poison ivy, which is quite common in the area. Rubbing up against this plant can cause painful rashes that last well over a week. (Lucky for me, I seem to be among those who have no allergic reaction to the plant, so I have never learned to identify it.) Another plant to avoid is the wood nettle, whose leaves are covered with little stinging hairs. Once I rode my bike through a patch of this stuff, and my skin erupted into painful red bumps. Fortunately, the effects from a wood nettle sting wear off in under an hour. 

The park also has a robust fungus population. Identifying mushrooms is a skill that I lack entirely; but visitors to the park have registered about two dozen species. The mushroom I most often notice is a Stereum, I believe, which grows on the sides of decaying trees. Indeed, saprotrophic mushrooms (which feed on decaying organic matter) play an essential role in the park’s ecosystem, allowing dead trees and plants to be broken down and returned to the soil. To name just a few of the mushrooms identified by park-goers, there is the dryad’s saddle, chicken of the woods, turkey-tail, resinous polypore, and honey mushroom. Some of these may be edible, but I would not take my chances. 

The park’s fauna is even more diverse than its flora. We may start with the arthropods—specifically, my least favorite animal in the park: the tick. There are two main species of tick in this area: the dog tick (Dermacentor variabilis) and the deer tick (Ixodes scapularis). Do not let these names mislead you, for both are happy to bite dogs, deer, or humans. The dog tick is bigger and is completely black, while the deer tick is smaller, with a brown body and black legs. Getting bitten by either is not fun, but it is really the deer tick that you should watch out for, since it can transmit Lyme disease. My dog would inevitably get a few ticks every summer (and got Lyme disease twice), and I have found three or four ticks on myself over the years. It is a good idea to check both yourself and your pets after a walk, especially if you went through a woody area. If you have been bitten, it is wise to watch out for any signs of Lyme disease, which can include a circular rash around the bite.

Coming in second for hazardous bugs are the mosquitos, which can also carry diseases. People in the area have been concerned about West Nile Virus for years now, and more recently there has been worry regarding Eastern Equine Encephalitis. Fortunately, the mosquitoes normally come out around dusk, and are mostly absent during the day. I ought also to mention the possibility of a wasp sting. Once, while walking on the Aqueduct Trail in the park, I accidentally stepped onto a wasp’s nest in the path. The angered insect flew out and stung my legs several times before I could run away—quite painful. But I think the chances of this happening are very low. More annoying than dangerous are the gnats that can sometimes be found swarming, particularly in low-lying areas of the park. Though they are completely harmless, some of them seem to be attracted to the secretions produced by your eyes, and so you can end up endlessly swatting away curious little bugs.

The park is also home to some beautiful insects. My favorites are the fireflies, which come out around dusk in summertime. They fly low to the ground, hovering slowly in search of prey. The light, created with chemicals in the abdomen, is used to attract small insects. Without this lure, the firefly would be quite an ineffective predator, since it is clumsy and ponderous in flight. Indeed, fireflies would be the perfect snack for any insectivorous birds—the easiest bugs in the world to find and catch—if they were not filled with bad-tasting chemicals. Thus they float around in security, lighting up the evening forest like little stars.

Also lovely are the many species of butterfly that flap about, including the majestic monarch butterfly. The best place to see them, in my experience, is the area around Bedford Road, in the fields of Buttermilk Hill. There the butterflies congregate in the hundreds, floating from flower to flower. Another attractive insect is the blue dasher dragonfly, which normally prefers watery areas like Swan Lake. They are graceful fliers, now hovering in place, and now darting forward at great speed—their long blue bodies flashing in the sunlight. A personal favorite of mine are the grasshoppers, which sometimes jump along the paths, their razor-like bodies cutting through the air. 

Insects are not merely seen everywhere, but they generate the loudest noises of the park. In the evening the crickets chirp with their wings, creating that comforting chorus of summertime. (Aside from these chirping crickets, however, there is the so-called camel cricket, which is a large, wingless species of cricket. Lacking wings, this species cannot chirp, and it is mostly known for accidentally invading basements.) The big noise makers, however, are the cicadas. The park is home to both the annual and the periodical varieties. The former are responsible for most of the daytime noise in summer, creating a kind of sonic sheet with their buzzing wings. Though constantly heard, cicadas are seldom seen, at least not in my experience. Both cicadas and crickets will stop chirping if you get too close; and in general their sounds are difficult to track down. The periodical cicadas hatch in enormous broods every 13 or 17 years (prime numbers make it difficult for predators to synchronize) and are quite a presence when they appear.

Rather inconspicuous to most park-goers, but fundamental to the park’s ecosystem, are the bees. According to a guide compiled by Sharp-Eatman Photography, over 100 species of bee have been found in the park. Most people, I suspect, will be surprised to learn that there are 100 species of bees in the world, much less in a relatively small area in New York. But bees are an incredibly diverse group. There are several species of bumble bees, carpenter bees, leaf-cutter bees, digger bees, and mining bees, to name just a few common groups. The bees are attracted by the many species of wildflowers found within the park, which include (to quote the guide) “wild azaleas, countless spring woodland bulbs, American white water lilies, four varieties of milkweed and large swatches of dogbane and meadow flowers.” European honey bees are also kept at the Stone Barns, where they help to pollinate the plants on the farm and in the surrounding park.

I have reached the limit of my knowledge of the park’s arthropod life, and yet this short description only scratches the surface. I am sure the park is home to a great many species of ants, spiders, and beetles; but it just so happens that I hardly ever see these creatures. They live their little lives in a small-scale world, vitally important to life in the park, but mostly invisible to people having a nice stroll.

Most visitors, I suspect, are far more interested in the birds. The Rockefeller State Park is also a wonderful place for birdwatching; indeed, it is recognized as an Important Bird Area by the Audubon Society. Over 180 species of bird have been identified within the park’s confines, which is well over twice as many birds as I could probably name. I should admit that I am not myself a skilled birdwatcher; I lack the patience and the good binoculars. But even a casual visitor will likely see a great many interesting avians.

The most common bird in the park may be the humble house sparrow. This bird is not even native to New York, but is an invasive species from Europe. Apparently it was first introduced into New York in an attempt to control the linden moth, and since then the bird has become ubiquitous. This is a shame, since the sparrow is not particularly pretty and its call is a tuneless chirp. The common starling is another species imported from Europe. Now extremely widespread across the continent, the bird was first brought to the United States in the 1890s; it was introduced into Central Park by a group of Shakespeare fans who sought to import every species mentioned by the Bard. This whimsical idea has cost the United States billions in damaged crops, and untold more in damage to native ecosystems.

The starling is—to my eyes at least—a rather ugly bird with a mangy look to it; and its song is not very pleasant either. But the bird does have its delights. In the autumn months, the starlings flock together in massive formations, shifting shape in the air like an ethereal wave. I have watched them take off, swarm, divide, rejoin, twist and turn, and then land—all perfectly in sync. It is wonderful to see.

But now we should discuss some of the park’s native species. My childhood favorite was the American robin, which was named after (but completely unrelated to) the European robin. These are the only birds which can commonly be found on the paths, where they like to look for worms. Also common is the red-winged blackbird, whose few scarlet feathers contrast sharply with its jet-black body. Its song is one of the most distinctive in the park, a tripartite raspy trill. (Describing bird calls in words is always tricky.) Even more brilliant is the cardinal, whose bright red plumage (among the males, at least) is impossible to miss. The blue jay is superficially similar to the cardinal, with its bright color and distinctive head crest. But jays are only distantly related to cardinals, and really belong to the crow family. The beautifully colored eastern bluebird is also unrelated to the blue jay, and is actually in the same family as the American robin.

One of the prettiest birds in the park is the American goldfinch, a petite yellow bird normally found in the more open areas of the park. Even smaller, and even harder to find, are the hummingbirds. In fact, the only reason I know they live in the park is that my brother set up hummingbird feeders in my backyard, and I have seen them fly in to have a snack. Few things in nature as are charming as a hummingbird; they way they move through the air is not quite birdlike (and not quite buglike, either), and the low-pitched hum from their wings is unmistakable. 

Among the more tuneful residents of the park is the black-capped chickadee, a small bird (about the size of a sparrow) with a complex and varied song. Its very name (“chickadee”) comes from one of its many calls, and is an immediately recognizable sonic signature. The tufted titmouse is a cousin of the chickadee, somewhat bigger more graceful in appearance, though lacking the chickadee’s elaborate melodies. (Why some birds develop elaborate calls while others stick with simple chirps? Does a chickadee have that much more to communicate than a titmouse? I will let the biologists ponder this one.)

The eastern towhee—a pretty mixture of red, white, and black—has a musical call, with three notes that sound somewhat like an augmented triad. Even more alluring is the call of the wood thrush. Indeed, many have considered the thrush’s song the most beautiful in the country, and I agree. Henry David Thoreau had this to say about this small brownish bird: “The thrush alone declares the immortal wealth and vigor that is in the forest. … When a man hears it, he is young, and Nature is in her spring.” To my ears, the thrush’s song has an odd auditory quality to it, sounding almost like water echoing in a closed chamber, or even like some digital effects on a sound editing program. It is wonderfully soothing, like the soft babbling of a river. 

If the thrush is the most beautiful melodist, the mockingbird is the most virtuosic musician of the area. As its name indicates, this bird can imitate a seemingly infinite range of sounds, from the calls of other birds to the whining of car alarms. I should mention that the mockingbird is probably more commonly found in the suburbs surrounding the park than in the park itself, owing to its preference for short grass and open areas. In reasonably short doses the mockingbird’s endlessly shifting song is enchanting; but when one is keeping you awake in the middle of the night, the charm wears off. Strangely, mockingbirds accumulate a repertoire of mimicked bird calls, not in order to trick other birds—who are not easily fooled—but instead to impress potential mates. Evolution is a wonderous thing.

One of the most charming sounds of the forest is not a call, but a rhythmic tapping or rattle. This is caused by the pileated woodpecker, whose large size and red crown make it easy to recognize. This tapping noise is not a byproduct of the woodpecker’s feeding, but is instead created intentionally as a display; the bird raps its beak against a resonant piece of wood, like a hollow log, in order to proclaim its territory. The woodpecker feeds by drilling into the sides of trees with its beak and gobbling up the ants and beetles living within the living wood. 

We cannot depart from the world of birds without considering the humble raven. While no beauty, it is the raven that participates in one of my favorite animal spectacles in the park. Ravens are vigorous defenders of their nests, and do not hesitate to attack birds much larger than themselves. Thus, any red-tailed falcons that get too close—whether they are going for the raven’s young, or simply by chance—are likely to be harrassed by one or two angry ravens snapping after them. It is amusing to see the formidable profile of a hawk in flight from the pugnacious ravens, like a F-16 being driven off by a couple Cessnas.

The red-tailed hawk is one of the park’s apex predators. They can be startlingly big—big enough to be mistaken for an eagle (that is, until you see a real eagle). Red-tailed hawks are carnivores whose diet mostly consists of rodents, particularly squirrels, though I do wonder if they ever try to attack stray cats or small dogs. Their call is a high-pitched screech that sounds like a war-cry. Much smaller is the American kestrel, a petite little hawk with muted coloration, which likes to eat large insects and small mammals. Intermediate between these two is the Cooper’s hawk, which in my experience is significantly less common. There may be owls in the park, too—either barred owls or the great-horned owl—but I confess I have never knowingly laid eyes on one.

The park is home to many water birds as well. If you are at Rockwood, looking out at the Hudson, you may be lucky enough to catch a glimpse of a bald eagle. But normally the best place to see water-loving birds is, unsurprisingly, Swan Lake. There you can find the modest duck—in many varieties, including the common mallard duck, with its charming emerald head. The pestilent Canada goose is sometimes present as well, though in mercifully small numbers in the park. (Perhaps the presence of so many carnivores makes the park unsafe for the goose’s young, and so they prefer more human-dominated areas.) Out in the middle of the lake I have seen the black profile of a double-crested cormorant as it dove for fish and then reappeared on the surface. 

More graceful avians include the great egret and the great blue heron. Both of these slender creatures tend to stand still in shallow water, waiting to snatch an animal with their long beaks. Coming across a heron—waiting motionless in a river—is one of my favorite moments in the park. It is stunning to see one stretch is long wings and take off. According to the website, the lake is home to “large-mouth bass, crappie, pumpkinseeds, bluegills, and bullhead catfish,” and this is not to mention the brown trout that are stocked every year. And this is not all: the egrets and herons also feast on some of the local amphibians, such as the common snapping turtle or the painted turtle. 

As you can see, there are an awful lot of birds in the park. I ought to stop now before this post becomes truly unreadable. And yet I cannot leave off without mentioning the biggest bird of all, bigger than the bald eagle or the great blue heron. This is the wild turkey. They are rather reclusive creatures, and so catching sight of one is not easy. Indeed, I cannot say whether they are often in the park, or only very occasionally. I have only seen a wild turkey once, many years ago, as I walked on a quiet winter day. The startled birds ran off (surprisingly quickly) through the forest and out of sight. 

The park has a few reptile and amphibian inhabitants, too, though thankfully they are not normally very visible. We have already mentioned the turtles, who like the water. The park is also home to several varieties of frogs and toads. Visitors have spotted and identified several: the bullfrog, the wood frog, the pickerel frog, the spring peeper, and the American toad. There are even salamanders. Snakes crawl among the underbrush, though thankfully no dangerous ones (well, not dangerous to humans, but lethal to the frogs). There are garter snakes, water snakes, milk snakes, and the tiny brown snake. I have never seen one of these snakes, and I am not particularly anxious to. (Technically, the park lies within the range of the timber rattlesnake, which is venomous, though I have never heard of any sightings.)

Now we come to the mammals of the Rockefeller State Park. We begin with the very smallest, the chipmunk. These adorable little creatures are most commonly seen scurrying about near the ground, usually at the base of a tree. They climb just as well as their larger squirrel brethren, but their burrows and much of their food is located at ground level, so it is not usual to see them in the tree-tops. The grey squirrel, one of the most common species of the park, is over twice as large as the chipmunk. Though so often seen as to be nearly invisible, the gray squirrel is quite an impressive animal. Not many mammals can climb and jump so ably; indeed the gray squirrel is one of the few mammals who can climb down a tree head-first. And if you try to prevent the squirrels from eating from your bird-feeders or fruit trees, you will find them to be wily and clever adversaries. Their name notwithstanding, a significant portion of grey squirrels are entirely black.

Before moving to Europe, I did not know how distinctive chipmunks and grey squirrels are to America. One does sometimes see gray squirrels in Spain, but there they are invasive. In the United Kingdom they have largely displaced the native red squirrel. Another of the squirrel species—an American icon—is the groundhog, which are also called woodchucks. (The name woodchuck has nothing to do with chucking wood, but comes from an Algonquin word.) These normally stay earth-bound, and live in underground burrows. Unlike the grey squirrel, which stores food away and is active all winter, the groundhog gorges itself and hibernates during the lean times. The chipmunk takes a middle road, and falls into a non-hibernative torpor (which is my winter strategy as well). 

There are some other rodents to be seen. The meadow vole (more often called a field mouse) makes it home in the park, though it is normally difficult to find. The eastern cottontail rabbit can sometimes be spotted at a distance; they are rather skittish, too. I suppose these rodents must be careful, considering the number of predatory birds circling overhead. Almost all nocturnal animals are not seen in the park, if only because it gets so dark that virtually nobody wishes to be there. Thus we miss the possum, a comically ugly creature that looks like an oversized rat. It is not a rodent at all, however, but a marsupial, the only one to live north of Mexico. This means that the young are born very small (the size of a dime) and reside in their mother’s pouch, just like kangaroos. 

Mammals do not just inhabit the trees and undergrowth; they compete with birds for the air. Several species of bats are endemic to the area, and they can be spotted in the waning light of summer evenings. The most common types are the little brown bat and the northern long-eared bat. Personally I like bats, since they help to control mosquito populations; but they can also transmit diseases to humans. The most deadly of these is rabies. Once, when a bat was discovered in—and chased out of—my house, my whole family had to go several times the hospital for the rabies vaccine, just as a precautionary measure. At present, bat populations all over the United States and Canada are threatened by a virulent fungus that colonizes the bat’s skin, a condition called white-nose syndrome. This has had a devastating effect on many bat populations, reducing some by over 90%. It remains to be seen how they will recover from this blight. 

One of the most common—and hazardous—animals of the area is the striped skunk. I know they live in the park, since my poor dog was sprayed twice. The smell is powerful and rancid. From far away it can smell vaguely like marijuana smoke, though from up close it is harshly chemical. If you keep your distance, however, skunks are harmless animals who mainly eat insects. Slightly more of a pest is the common raccoon. Once I was surprised when, seemingly out of nowhere, a group of raccoons appeared, pushed over a nearby garbage can, and then carried off their loot into the forest. They are very dextrous and intelligent animals, and able climbers. During a rainstorm I witnessed a raccoon climb to the top of an electricity pole and huddle their for well over an hour. Raccoons, like skunks, are only really dangerous if they are infected with rabies. A police officer shot a rabid raccoon at the top of my street some years ago. If you are unlucky enough to get bitten, you will need to get the vaccine immediately.

The park is also home to many predators. By their nature, these carnivores are quite expert at sneaking around unheard and unseen, and so catching sight of one is an uncommon experience. The red fox prowls around the park, eating pretty much anything it can find, be it bird, amphibian, reptile, or mammal, as well as some seeds and grasses. I have heard of bobcats occasionally appearing in Westchester county, but I believe there are not many; competition with coyotes often drives them away. And the Rockefeller State Park Preserve definitely has coyotes. Some nights, you can hear their high-pitched yelps and howls echoing through the forest. It can be very loud, and quite eerie.

I have only seen a coyote on three or four occasions—always at a distance, and always briefly. The only exception to this was one odd sighting, right in the middle of Tarrytown, of a coyote chasing a domestic cat. The cat escaped by clawing its way up a tree. Coyotes are bigger than foxes—though smaller than most dogs—and are more ferocious hunters. Close cousins of the gray wolf, coyotes prefer fresh meat and are capable of taking down animals as big as deer (but they normally go after immature animals). They are very effective predators, and can kill porcupines and rattlesnakes, as well as many species of birds, including wild turkeys. Coyotes are not pack animals, but instead form pair-bonds, which are probably more stable than most human relationships. Unless they are rabid, they pose no threat to humans.

Coyotes became top dog after gray wolves were hunted out of the region, which was done over 100 years ago to protect livestock. Now the biggest canines in the park are domestic dogs. Another predator that has been eliminated from the area is the cougar (or mountain lion, or catamount—it has many names), which became locally extinct about 200 years ago. Black bears have occasionally been sighted in Westchester County, though I have not heard of any within the park. The lack of predators may make the area a little safer, for humans and for cows, but it did greatly upset the ecosystem.

The most apparent evidence of this is the huge profusion of deer. The white-tailed deer is the biggest animal in the park (that is, not counting the domestic cows); big bucks can get even heavier than most adult humans. They are everywhere, and often they are not particularly skittish around people. Many will not even bother to run away when you walk by. The most flighty seem to be the males with fully-grown antlers, which can be seen starting in late spring. Perhaps they are nervous because the park does allow some limited bow-hunting of deer in one section of the preserve. This is done as a needed control over the deer’s explosive population. 

This description, long as it is, does not even come close to fully capturing all of the manifold forms of life within the park. Language is linear, so we must go through these many species as a long list. But life is not a list, not even a long one. Every level and layer is intimately bound up with every other, creating a dense web too complex for us to wrap our minds around. This is the problem of organized complexity. We can readily understand things that are complex but disorganized (like the motions of gas particles) or simple but organized (like the orbit of a planet); but when there are so many variables, all influencing one another in precise and specific ways, we find ourselves grasping in the dark. This partially explains why humans so persistently disrupt ecosystems. We cannot tweak them by simply eliminating the parts we do not like—such as wolves or mosquitos—since every change has ripple effects through the whole system.

To see all of these particulars as one enormous whole is the challenge of the naturalist. But it is also what comprises the real beauty of a natural place. Organized complexity, after all, is what separates a forest from a botanical garden or a zoo, wherein species are divided and labeled. And this is also, I think, why natural spaces are so refreshing to us. Every human-made environment is composed of simple shapes—lines, circles, rectangles—all arranged simply enough for us to easily navigate them. From a suburban neighborhood to the inside of a cathedral, this holds true. Natural spaces betray no such simple geometry or geography. By comparison, nature can appear chaotic or disorganized; and yet if it were truly so we would not find nature so aesthetically pleasing. Rather, natural spaces are highly organized, but along non-intuitive lines; and this lack of obvious arrangement is why, I believe, it can feel so refreshing for us to take a walk in a forest. Sensually and cognitively, it is a richer experience.

Henry David Thoreau famously went into nature and found the meaning of life—or at least, the meaning of his life. I cannot say that the Rockefeller State Park Preserve has been to me what Walden Pond was to him. Yet the park has been a constant, comforting presence in my life, a place of beauty and continuing wonder. Even now, there are still some corners I have yet to explore, and so many plants and animals I have yet to know. Like all of nature, the park can teach many lessons, provided you are a willing pupil. The principles which shaped the park are the same as those which have shaped the entire earth; and so understanding one small plot of land may be the best way to come to grips with the cosmos. If the park has any moral lessons to teach, it is the lesson of all nature: that life goes on. I do find a sort of comfort in the thought that, whatever happens to me, this buzzing, blooming world will continue.

But the park has another lesson, too, and that is the value of cooperation. The Rockefeller State Park Preserve would not exist without the generosity, care, and work of thousands of people—from the original donors of the land, to the volunteers who help to combat invasive species, to the casual visitor who takes care not to litter. Wild places do not simply exist nowadays, but must be actively maintained. It is one of the ironies of our history that we only really began to savor wilderness when much of it had already been destroyed. Now, without places of refuge like the park, we will be condemned to wander among asphalt landscapes of endless surburbia. For our own sake—if for nothing else—we must fight to protect it.