Autumn Migration at Rocky Point Marsh, October & November, 2014

Rocky Point Marsh, like so many of nature’s oasis’ serves as a way-point for migrating birds. The Rockaways, where the marsh is located, are barrier islands situated within the so-called Atlantic Flyway and are a convenient navigational aid as birds make their way down the East Coast, to, and past, Cape May, New Jersey.

The importance of a salt marsh’s varied habitat becomes as critical at this time of the year as it would be during nesting season. Birds will stop to feed and fatten-up for the next leg of their energy-consuming journey. Seeds and berries, as well as insects and fish offer convenient access to those birds with peculiar diets. Raptors will follow avian prey during migration so that they can also add more calories to their body mass for the continuation of their annual southern excursion.

The advent of autumn brings shorter periods of daylight. Being hard-wired into nature’s grid, birds take note of this; when the time is right they head south. Weather patterns this time of year often produce winds from the north; birds habitually take advantage of the free ride a tail-wind offers. Many bird species fly at night during migration; it is thought that they may do so to avoid predators or to use the stars as navigational aids. Raptors migrate mostly by day when the heating of the earth’s surface creates thermal air masses, which ease their passage. Birds will stop to rest in welcoming areas, such as salt marshes; most will forage early in the day and then again late in the afternoon.

Not all birds of the same species will begin migration at the same time. The sex and the age of the birds seems to play a role in determining precisely when migration will begin for an individual. In addition, certain birds, which will winter locally, merely disperse in order to ensure that adequate food resources are obtainable.

Habitats also undergo a metamorphosis; leaves change color or drop away as the weather cools, altering nature’s color palette. Summer’s greens give way to yellow, orange and red, then tan and gray as autumn turns into winter. Decaying plant matter fertilizes the earth adding nutrients for next spring’s explosion of new life. Many plant species (with the help of birds and insects) disperse their seeds into this mix, adding to a salt marsh’s inherent ability to support a rich biodiversity.

The following images and observations were made during the months of October and November, 2014.

 

It’s still mid-October and the weather has been relatively mild. So, at this point in time, colors have not yet changed in any dramatic way. This view looks towards the western end of the marsh; compare to similar images in the previous blog posting. Date: 10-17-2014.

In the calm waters of the eastern edge of the marsh pond, these shoots of grass were surrounded by tiny gas bubbles. This was a consistent phenomenon over an area of many square yards. Date: 10-17-2014.

 





One week later, the tide came in fully, completely flooding the marsh. The camera is pointed slightly north of east, at the entrance formed by Super-storm Sandy. In fact, the image was made almost two years to the day that the storm devastated the northern east coast. Date: 10-25-2014.



Another interesting phenomenon seen in a quieter flooded segment of the western edge of the marsh, were these gas bubbles. They covered many square yards of the marsh’s substrate, a few inches below the water’s surface. The remains of a Ribbed Mussel (Geukensia demissa) is seen at upper right. This bivalve helps filter the water, leaving fecal matter behind, which helps provide nitrogen as a plant nutrient. It is also a food source for birds that frequent the marsh, such as the Willet. Date: 10-25-2014.

Looking like extra-thin string-beans with warts, this Saltwort (Salicornia) lies entangled in grass just behind the dune line at the marsh’s western edge. Green throughout the summer months, a close look at some of the plant’s shoots will reveal that they are typically beginning to turn orange-red as autumn takes hold. Date: 10-25-2014.

 

Although this image was made one week prior to the one above, his bit of Saltwort (Salicornia) has already turned completely red. Date: 10-17-14.

This stand of American Beach Grass (Ammophila breviligulata) appears to be in seed. A dominant species on the Atlantic coast down to North Carolina, this hearty and rapidly-growing plant is vital for the stabilization of the dune line. Date: 10-25-2014.

A clammy, rainy day greeted your humble narrator on the first day of November. The marsh pond is filled and one can also see how most of the trees in the background have become completely denuded of foliage. Yet, there are still bits of color here and there. In this image the camera faces south. Date: 11-01-2014.

A few minutes later, anchored in the same location, the camera faces east. Date: 11-01-2014.

What a difference a week makes! As the camera faces west, on this beautiful, yet “crisp” morning, it provides a view along the dune line behind the beach that fronts Jamaica Bay. These dunes were completely flattened two years ago by Super-storm Sandy, but have re-built themselves quite handily, probably because most of the “rhizomes” (lateral root systems from plants) remained intact below the surface. Date: 11-08-2014.

This appears to be a Red-tailed Bumble Bee (Bombus ternarius), which is common in the east from Nova Scotia to Georgia. It was observed at close quarters as it went busily about its business atop this Seaside Goldenrod (Solidago sempervirens). Date: 10-25-2014.

What is most probably a juvenile Coopers Hawk (Accipiter cooperii) surveys the marsh from a low altitude. A hunter of birds and small mammals, this raptor’s wing and tail shape assures it of maneuverability as it stealthily pursues prey through the woods. Illustrating how Hawk identification can be a challenge, particularly for less-experienced birders such as I, this could also be a Sharp-shinned Hawk (Accipiter striatus). Date: 10-17-14.

This Golden-crowned Kinglet (Regulus calendula) perches in a thicket along the edge of the marsh. With a diet consisting almost exclusively of insects, this small bird seems quite resistant to autumn’s cooler temperatures. Date: 10-25-2014.

The Ruby-crowned Kinglet (Regulus satrapa) also feeds mostly on insects, but will also eat berries and seeds; in this image this little fellow has just launched itself from the branches of Poison Ivy. Although unseen here, there is a red crest hidden on top of its head, which will be deployed if the bird becomes overly excited. Date: 10-25-2014.

The most often seen Warbler at Rocky Point, the Yellow-rumped Warbler (Dendroica coronate) comes in two main forms; this one is seen in the east and is a “Myrtle”. The “butter-butt’s” diet consists of insects and berries, with the latter being consumed in winter months. Date: 11-08-2014.

The vociferous Song Sparrow (Melospiza melodia) perches on a tree branch. Its diet consists mostly of insects and seeds, but it will sometimes eat small crabs and mollusks. Song Sparrows are common visitors year-round at Rocky Point. Date: 10-25-14.

This rather handsome White-throated Sparrow (Zonotrichia albicollis) struts his stuff for the camera. Another common species at Rocky Point, its diet consists of insects and seeds, as well as berries; it will also eat snails and is well served in a marshy habitat. Date: 11-08-14.

A cousin to the sparrow, the Dark-eyed Junco, Slate-colored (Junco hyemalis) is most commonly seen hunting for seeds on open ground. It supplements seeds with insects and berries. On this day, it was the predominating bird species at Rocky Point. Unusually, this individual seems to be of the “pink-sided” or “mearnsi” race; if this is so, he is far from his normal range. Date: 11-08-14.

A ground forager, the Winter Wren (Troglodytes hiemalis) is most often observed in tangled undergrowth. An insectivore, it will also occasionally dine on small fish and some berries. Date: 11-08-14.

 The Hermit Thrush (Cartharus guttatus) often lingers for a time in the north, beginning its migration late in the autumn. Feeding manly on insects, it will also eat a large variety of berries. Date: 10-25-14.

The Downy Woodpecker (Picoides pubescens), which is very similar in appearance to the Hairy Woodpecker (Picoides villosus), can be differentiated by its much shorter mandibles as well as its smaller size. Its main meal consists of insects, but it will eat seeds and suet from bird feeders, as well as berries. Date: 11-29-14.

A pair of Northern Flickers (Colaptes auratus), perch on one of the supports of the marsh’s Osprey nest platform. This is the so-called “yellow-shafted” form seen in the eastern parts of North America. Primarily an insect-eater, Flickers are often seen feeding on the ground in all seasons. Date: 11-29-2014.

A relatively late autumn migrant and an early spring migrant, the Eastern Pheobe (Sayornis nigricans) is a so-called “Flycatcher”. It feeds mostly on insects, but will also eat berries and some fruits. Date: 10-25-14.

A year-round resident in New York, there is no mistaking the Northern Cardinal (Cardinalis cardinalis), either by sight or by sound. Its large, powerful mandibles are equally at home devouring insects and vegetable matter; snails are also on its menu, making a salt marsh an ideal habitat. Date: 11-08-14.

This trio of American Goldfinches (Corduelis tristis) are feeding on a stand of Seaside Goldenrod (Solidago sempervirens). They are in their more cryptic winter colors but still retain their black wings and white wing bars. Like many birds, they eat mostly insects in the warmer months, switching to seeds during colder months. Date: 11-29-14.

 

These two images were made in the center of the western part of the marsh. The first one looks south-east, while the second looks north-west. Note that the trees are denuded of their leaves and most of the grasses are showing very little green. Date: 11-29-14.

As the weather cools, some plants prepare to spread their seeds around in preparation for spring, as this Common Reed (Phragmites australis) is doing. The seeds shown are ready for distribution by the wind, using their silken bristles as parachutes. However, this plant’s main form of reproduction is through its rhizomes (lateral underground root systems). Date: 11-19-14.

These two images were made from virtually the same view-point. The upper image has the camera facing north-east, looking out towards Jamaica bay. The lower image is looking almost directly north, with the Manhattan skyline on the far horizon. Difficult to tell from this angle, the surface of the water in the marsh sports a thin layer of ice, indicating that it is of relatively low salinity. Date: 11-29-14.

Probably one of the most devastating consequence of human ecological ignorance is the presence of feral domestic cats throughout the Rockaways. Often abandoned or simply let loose for the night by their owners, these predators have a profound effect on bird populations; it is estimated that millions of birds are killed each year by this completely preventable man-made scourge. This rather fat creature is crossing the entrance to the yacht club on his way to hunt in the marsh; the presence of your narrator did not disturb him in the least. Date: 11-29-2014.

New York City’s Police Department has an Aviation Unit based at Floyd Bennett Field, part of the Gateway NRA complex, located in Brooklyn. The NYPD is in the process of replacing their helicopter fleet with the Bell Model 429 (upper left); the Bell Model 412 (bottom right) will be retired. Both of these rotary-wing aircraft are outgrowths of designs that made their first flight in 1956 (the 412) and 1966 (the 429). These two helicopters were photographed over Jamaica Bay, from the marsh. Date: 10-17-14.

 I will close this entry with an image made in August, 2014, at Fort Tilden. Almost two years after Super-storm Sandy, most of the dune line that was eradicated has still not begun to repair itself. Likewise, the maritime forest still plainly exhibits the effects of the devastation wrought by the storm.

All text and photographs by Frank V. De Sisto unless otherwise indicated.

Credit where it’s due:
This time around I’d like to thank Genie for help in confirming the identity of some vegetation.

Sources consulted for this blog included:

“The Warbler Guide”, by T. Stephenson & S. Whittle. 2013, Princeton University Press, ISBN9780691154824.
A relatively new title, this book should prove to be indispensable to students of the subject. It provides detailed descriptions, schematic artwork, a guide to interpreting songs and a vast amount of excellent photographs. Disclaimer: I had met Mr. Whittle some years ago when I first became hooked on birding; he proved most gracious in answering some questions from this novice at the time and many times since.

“The Stokes Field Guide to the Birds of North America”, by D. Stokes & L. Stokes. 2010, Little, Brown & Co., ISBN9780316010504.
This highly-regarded volume is one of many titles by this acclaimed husband and wife team. Profusely illustrated with photographs, it also includes a handy CD with recordings of over 600 bird sounds.

“Kaufman Field Guide to Birds of North America”, by K. Kaufman. 2000, Houghton Mifflin Co., ISBN9780618574230.
Laid out in the typical compact format of classic field guides, this volume is set apart from some by the use of photographs instead of paintings. What differentiates it from other photo-based offerings is that the images are digitally manipulated to show only the bird, from several angles, without any distracting background.

“Hawks in Flight”, by P. Dunne, D. Sibley & C. Sutton. 1988, Houghton Mifflin Co., ISBN9780395510223.
This unique and slim volume takes a different approach to identifying the subject while in flight, using line drawings and B&W photographs. This is extremely useful when all the observer can see is the underside of a bird in flight.

“Hawks from Every Angle”, by J. Liguori. 2005, Princeton University Press, ISBN 0691118256.
Another helpful book for Hawk watchers, this title is based on using color and B&W photographs. It also has information on where to go and when to be there in order to observe Hawks, as well as tips on optics and photography.
“Lives of North American Birds”, by K. Kaufman. 1996, Houghton-Mifflin, ISBN0618159886.
This book picks up where the typical field guide leaves off, concentrating on how and where birds live. It is illustrated with color photographs and range maps. Taking each North American species in turn it details such things as habitat, diet, behavior, migration, and conservation status, all in layman’s terms.

“The Sibley Guide to Bird Life & Behavior”, Edited by D.A. Sibley, C. Elphick & J.B. Dunning, Jr; illustrated by D.A. Sibley. 2001, Knopf, ISBN9781400043866.
With a similar goal to the title listed above, this weighty volume compliments Mr. Kaufman’s effort quite nicely. This book is divided into two main parts, the first of which details many facets of bird biology and behavior, as well as external factors that affect them. The second part contains details on the specific habits of various species broken down into family groups.

Rocky Point Marsh needs your help. To volunteer for service contact National Park Services Ranger Tony Luscombe at: dcalato6@gmail.com

 For more photos of Rocky Point as well as other locations within the Gateway NRA complex, visit: www.frankdesisto.com