Tuesday, November 25, 2008

Harriers


© Dave Spier

At this rate, it just might spend the winter here. Sometimes it flies close to the building, passing the west windows, and then disappears across the field. I doubt it's hunting the birds at the feeder, but they are within the realm of this raptor's diet. Mostly it flies low over the grasslands and the marsh while it looks for small mammals, especially Meadow Voles (also called field mice) which are caught with a sudden pounce. Sometimes this large bird's flight drifts lazily back and forth, then stops momentarily to hover. In warmer weather it hunts snakes, frogs and insects. When all else fails, carrion is eaten.

The Northern Harrier, once known as the marsh hawk, is a slender and buoyant hawk with a somewhat owl-like face. The hawk's long wings and tail are designed for life in the open. If it tips a bit sideways toward you, watch for the distinctive white rump patch. When soaring, the wings are held in a shallow V with the tail fanned. At low altitudes, the tail is usually closed and the wings held flat to the sides. In a steep glide, the wings are sharply bent and swept back like a fighter jet.

In the winter, harriers hang around with Short-eared Owls and share the same fallow, grassy fields where mice have had time for a population explosion. Both raptors will use fence posts as hunting perches while they listen for prey. Though unrelated, the facial disks of both harriers and owls are thought to help focus sounds on the ears.

The harrier's Latin name, Circus cyaneus, refers to its circling flight and the supposedly blue plumage of the males. The color is actually gray, but that's only half accurate because females and juveniles are brown, an unusual disparity for raptors. Juvenile harriers are orangish underneath, like the two photos. The name "harrier" is Old English for "harassing with hostile attacks." Other colloquial names include blue hawk, mouse hawk and white-rumped hawk. Males are smaller and more agile and catch smaller prey, including birds. The harrier flying past the Montezuma Audubon Center (Rt. 89, Savannah, NY) was a larger, brown female probably more intent on a larger meal than the tiny goldfinches at the feeder.

Harriers nest in the marshes at Montezuma National Wildlife Refuge (between Rochester and Syracuse, NY). Last April I watched a female repeatedly carry nesting material in her beak and then drop down into the same patch of heavy vegetation. There are indications harriers also may nest in the Northern Montezuma Wetlands Complex around Savannah (Wayne County, NY). They almost certainly nest in the Lakeshore Marshes Wildlife Management Area near Lake Ontario in northeastern Wayne County as well as Howland's Island in Cayuga County. The female does all the incubating while the male brings food. After the eggs hatch, the male continues supplying prey, but only the female tears it up and feeds the young. If something happens to her, the nestlings will starve, even though the male continues to drop whole prey into the nest.

Harriers breed from Alaska across Canada to the Maritimes and south into the United States as far as a line from California to Pennsylvania. Most harriers head south for the winter and return in the spring.


(This copyrighted article - slightly revised here - and photos first appeared in the Times of Wayne County, November 24, 2008. All rights reserved.)


 

Friday, November 14, 2008

November Trails


November Trails
This blog has been reposted in two parts with additional photos.
part 1 and part 2

Friday, October 24, 2008

Common Loons


Common Loons
© 2008 Dave Spier.
Native Americans referred to this bird as the "Spirit of the Northern Waters." Common Loons breed across Alaska, the entire width of Canada, and the northern-forest zone from Minnesota to the Adirondacks and New England. During their migrations they often stop in the Finger Lakes Region. I've found small flocks resting on Lake Ontario off Chimney Bluffs during calm weather in October and at least several loons will use the Widewaters portion of the Erie Canal in November. This stretch is unaffected by draining the canal for winter because Ganargua Creek passes through here. A large number of loons follow Cayuga Lake as they head south. They're most likely heading for the Atlantic coast where the juvenile birds will remain for three or four years before returning north, but some will go as far as the Gulf Coast. Loons in the western part of their range spend the winter on the Pacific coast. In early spring I've found returning adult loons near the Canandaigua City Pier before boating season gets under way and disturbs them. One of the birds caught a very small sunfish while I was watching.
Loons are large birds. They measure 32 inches in length and have a wing span of nearly four feet. Males are larger than females. From March through October, the adults sport high-contrast black and white plumage. The heads and beaks are black, their necks have white or gray bands, the breast and belly are white, the sides black and the back is extensively checkered. The only color is in the red eyes. Juvenile loons, and adults in winter plumage, are overall gray or dark gray with white on the throat and upper breast. They may have a faint, light gray, partial band around the neck.
On the water, loons ride low like a submarine, an appropriate metaphor becuase they dive to catch their food. A number of adaptions helps them do this. Their feet are far to the rear and to the sides to facilitate paddling underwater and their marrow-filled bones are thicker than other birds. For this reason, loons are heavy birds that require a long stretch of open water to get a running start to become airborne. Once in flight, their thick necks are balanced by large feet trailing to the rear. The relatively small wings make diving easier, but flying is more laborious. The location of the feet at the rear makes it nearly impossible for loons to walk on land, so they nest on the edge of islands where they can just slip into the water if danger approaches.
Loons face a number of manmade threats. Air pollution from mid-western power plants and auto emissions contains sulfuric and nitric acids and mercury. These are carried eastward by prevailing winds and fall as acid rain, in turn killing many of the small fish and organisms that loons depend on for food. Chicks can starve to death before four weeks of age. Acidic water also converts mercury to an organic form that enters the food chain and becomes concentrated in loons at the top of the ladder. Methyl mercury attacks the bird's nervous system, interfering with its ability to catch fish. In high enough concentrations, the birds die from mercury poisoning.
Loons also become entangled in discarded fishing line and die of lead poisoning after they ingest old fishing sinkers which are mistakenly picked up from the bottom along with the small stones used to grind up food in their gizzards. These hazards also afflict a host of other waterbird species. Shoreline development and increased recreational use of northern lakes pose additional threats to loons as they lose traditional nesting sites and face increased boat and jetski traffic,
If you see a loon this fall, you can contact Dave at northeastnaturalist@yahoo.com More nature photos can be seen at http://www.flickr.com/photos/dave_spier and http://picasaweb.google.com/northeastnaturalist

(This copyrighted article and photos first appeared in The Times of Wayne County, October 20, 2008. All rights reserved.)


Monday, September 1, 2008

Golden Garden Spiders

A female Argiope aurantia, the golden garden spider, hangs upside down as it finishes wrapping its prey in a gauze straight jacket. The heavy zig-zag stitching on the web (called stabilimento) is believed to warn birds that might otherwise wreck the web. The yellow flowers supporting the web are brown-eyed Susans 'Goldsturm.'
© Dave Spier photo # D050779 [resolution reduced for web use]

Golden Garden Spiders
© Dave Spier


The small patch of Brown-eyed Susans 'Goldsturm' has grown over the years and it now spreads along the entire east side of our patio. Sheltered from north and west winds, it catches the morning sun that burns off the dew. Yesterday I was leaving the house and just walking past when a new visitor caught my attention. A great, circular web stretched through a gap between several of the taller plants. A white, zig-zag stitching reinforced the center and there, hanging head down, was a huge multi-colored spider wrapping her prey. The eight black and pink legs easily spanned two inches. The egg-shaped abdomen was black with bright yellow markings. This was a Golden Garden Spider, Argiope aurantia, also known as the Black-and-yellow Orb Weaver.

I've also found these spiders in shrubs, tall grass and fields of wildflowers. They build their elastic webs by first throwing a "bridge" thread (a loose strand of silk) carried on air currents to a second support. From the center of the bridge, they drop down with an anchor thread to form a tripod. A box frame is built around the intended area and more radial spokes are added. Then a few quick spirals of non-stickly thread allow the spider to walk anywhere on the web. Finally, a tight pattern of sticky spirals completes the trap and the spider waits for its victim. They ignore the high-frequency vibrations of dangerous prey such as wasps, but quickly dash out and wrap more delectable goodies such as grasshoppers and other juicy insects. With its potential meal in a gauze straight jacket, the spider bites with fangs and injects a paralyzing venom. Then digestive enzymes are pumped in to liquify the soft body tissues, turning them into a soup that the spider sucks out. All that's left is the insect's exoskeleton.

By the end of the day, the sticky threads are too dry to be effective, so the spider eats the web and spins a new one. The silk, produced by spinnerets under the tip of the abdomen, is a liquid protein that hardens when it contacts the air. Besides the two types used to make webs, their is a third silk used to wrap prey and then another silk to wrap and protect the spider's eggs. Silk can also be used for "ballooning," sort of a magic carpet ride on the air. The heavy, zig-zag stitching, called stabilimento, across the central hub of the web is believed to warn birds that might otherwise blunder through the web. This saves the spider time, energy and material in prematurely rebuilding the web.

Late summer is spider season. Look out across any field just after sunrise and notice all of the dew-soaked webs catching the morning light. Each of these is both home and kitchen to a spider.

Contact Dave at northeastnaturalist@yahoo.com or Facebook. There is also a Facebook page for The Northeast Naturalist.

(This copyrighted article and photo first appeared in the Times of Wayne County, September 1, 2008. All rights reserved.)

Wednesday, August 27, 2008

Goldenrods

Goldenrods -- © 2008 Dave Spier

First, to clear the air, goldenrod does not cause hay fever or allergies. That job is done by ragweed, a distant relative with tiny, inconspicuous green flowers and copious amounts of powdery, wind-blown pollen. Goldenrod, on the other hand, has sticky, relatively-heavy pollen carried from flower to flower by insects such as wasps and bumblebees. In fact, the yellow color of golenrod serves to attract the various insects needed for pollination.

Wherever there's abundant sunshine, goldenrods take over with a tangle of underground roots and chemicals that inhibit the growth of competitors. It takes a number of years, but they can dominate small patches of real estate and this continues until shrubs rise above the challenge and begin shading the goldenrods. Assuming there are no other disturbances, trees eventually win the battle for sunlight and recreate a forest, but that takes decades. That said, there are even two species of goldenrod, the Zig-zag and the Blue-stemmed, that survive as individuals or small patches in some woods.

There are actually dozens of different goldenrod species, each adapted to slightly different growing conditions. Many have offset, but overlapping, growing periods so they are not all competing for insect attention at the same time. The individual blossoms are crowded together, usually along the top stems where they are most visible. To see the differences in their basic structure, one needs to look closely or use a magnifying lens. Many resemble miniature daisies. Of course, many things do because the daisy family (usually called the aster family) contains one-tenth of the world's flowering plants. Their basic design is a central disk of compact florets surrounded by showy petals called rays. There are a few exceptions to this rule, including ragweed, which has lost (or never developed) the corolla of rays. Unfortunately, ragweed blooms at the same time, and in many of the same habitats, as its showy cousins that get the blame. So, if you can, spare the gold and pull the ragweed.

You might call me the goldenrod ambassador.

Contact me at northeastnaturalist@yahoo.com

(This copyrighted article and photo first appeared in the Times of Wayne County, August 25, 2008. All rights reserved.)

Monday, August 25, 2008

Painted Turtles

Painted Turtles
© 2008 Dave Spier.
Perhaps the commonest turtle in New York State is the painted. Often seen sunning itself on a log, and frequently basking in a group, the painted turtle will slide into the water at your approach. It also can be seen crossing roads and a number of people, myself included, are inclined to carefully stop and help the turtle across before it becomes another road pizza.
Painted turtles are recognized by smooth, dark-green or black shells edged with red plus colorful patterns of red and black on their necks and legs and yellow stripes on the head. The local race (subspecies) in the Finger Lakes Region is the Midland Painted Turtle, Chrysemys picta marginata. The average length of the shell is five inches with a record over seven inches. Females are generally larger than males. The large scutes, the pieces that make up the carapace, or top shell, alternate instead of running straight across the back. If you turn the turtle over, the plastron, or bottom shell, often has a dark blotch that individually varies in size and shape. Our subspecies ranges from southern Ontario and New England to Tennessee. Along the east coast, it interbreeds with the eastern race of this species which has a plain, pale plastron.
The painted turtle's diet varies with age. Adults eat mostly aquatic vegetation, but youngsters eat high-protein insects, crayfish, worms, carrion, tadpoles and small mollusks like snails which they find in any shallow body of water, be it pond, marsh, ditch or stream backwater. Lacking teeth, they depend on beaks with sharp cutting edges and inside the jaws are flat, crushing surfaces. Like all reptiles, they are cold-blooded ectotherms that warm themselves from the rays of the sun. The food they eat is used for growth and cell repair and not for generating body heat. As a result they need less food than warm-blooded birds and mammals.
Unlike the amphibians from which they evolved, reptiles have scales or bony plates covering thick, waterproof skin. This reduces loss of body moisture and allows them freedom to roam far from water. In the case of turtles, the bony carapace is fused to the spinal vertebrae and ribs. Once fully grown, the armored shell offers excellent protection against predators. Young turtles are not so fortunate and may be eaten by anything from raccoons to night-herons.
Reptiles differ from amphibians in another important respect. They are not restricted to laying eggs in the water. Amphibian eggs resemble fish eggs and are fertilized externally. Reptile eggs are fertilized internally. Many reptiles, turtles included, lay eggs covered with leathery shells and these are buried on land after digging a hole in damp soil using their clawed hind feet. Painted turtles generally lay half a dozen elliptical eggs in a clutch between mid-May and July. Incubation takes 10 or 11 weeks. Parents never care for their young which are fully developed and totally on their own from birth.
Turtles as an order have been around for an estimated 200 million years. Obviously, their basic design, two external shells connected with a "bridge," has proven highly successful in the survival game. The name "turtle" comes from "tortue," the French word for tortoise. The scientific name, Chrysemys picta, means "golden tortoise painted."
Underwater, basking turtles of the genus Chrysemys have a preference for what fishermen call structure. Fallen branches, logs, weed beds or sharp dropoffs provide escape cover for both turtles and fish. The next time you're out fishing, let the common painted turtle lead you to structure and probably a better catch.
Finally, turtles spend the winter buried in mud at the bottom of communal hibernating ponds. Lying dormant, they obtain oxygen through the linings of the mouth, throat and rear end of the gut. Makes me glad I'm not a turtle.
[For a discussion of the snapping turtle, see the May 21, 2007 issue of the Times of Wayne County: http://www.waynetimes.com/052107.pdf and go to p. 18 of the PDF.]
Send your comments and suggestions to northeastnaturalist@yahoo.com
(This copyrighted article and photograph first appeared in The Times of Wayne County, August 18, 2008. All rights reserved)

Bluegills


Bluegills
© 2008, Dave Spier
The Bluegill (Lepomis macrochirus) is a member of the Sunfish Family. Based on technical characteristics, it is related to Largemouth and Smallmouth Bass, Rock Bass, Black Crappies and the Pumpkinseed (or Common) Sunfish. Bluegills are identified by blue edging on the gill cover and a dark "earflap" plus a dusky thumbprint-like marking on the rear of the top (dorsal) fin. They are colored dark green on the back, white on the belly and yellow or orange (or sometimes dark gray) on the breast. Down South, they are called bream. They are now widespread in New York as a result of being stocked to serve as food for bass in farm ponds.
Bluegills spawn in early summer. The male builds a nest by fanning his tail to create a circular depression in shallow water. This removes silt that might smother the eggs. The female then joins him and they slowly swim around the nest while emitting eggs and sperm which settle to the bottom. The male guards the nest until the young disperse. At this stage, the third-inch long juveniles are transparent and move about freely. When they reach an inch in length, they return to hide in the vegetation of the lake, pond or slow-moving stream where they were born. They feed on tiny animals collectively called zooplankton. As they grow, they eat insects, crustaceans, other invertebrates and sometimes smaller fish. Older fish also consume plant material. Bluegills have been known to live 10 years and reach a length of 10 inches. In warmer climates they grow to a record 16 inches and just under five pounds.
All sunfish have sharp spines on four of their fins. These points help protect them from predators like bigger fish and large birds. If you've ever caught a sunfish and carelessly grabbed it, you know about these spines.
Send your comments to northeastnaturalist@yahoo.com
(This copyrighted article and photo first appeared in the Times of Wayne County, August 11, 2008. All rights reserved.)

Tuesday, July 29, 2008

PURPLE LOOSESTRIFE

Purple Loosestrife -- The Beautiful Invader
© 2008 Dave Spier
Purple Loosestrife is a tall, wetland plant sporting beautiful magenta flowers with six (sometimes four or five) petals surrounding a small yellow center. Clusters of these blossoms grow in dense whorls around a fuzzy, square stem. Pointed leaves grow in opposite pairs (sometimes whorls of three) below these flower spikes. The species is native to Europe. As early as Roman times, it was tied to the yokes of oxen in the belief that it appeased or ended strife and unruliness between the animals as they plowed. It was said to "loosen strife," hence the name loosestrife.
How could such a beautiful plant be a problem? We'll get to that in a moment.
Purple Loosestrife (Lythrum salicaria) was brought to eastern North America in the early 1800's to be used in flower gardens. If it had stayed where it was planted, we'd have little trouble. Since then it has spread westward across much of Canada and the United States. Loosestrife is a hardy perennial that takes over wetlands, crowding out the native cattails that our wildlife depends on. To give you an example, Black Terns (a declining species) depends on old, broken cattails for nesting material. The stiff, almost woody stems of loosestrife are not readily broken. Loosestrife is almost worthless from wildlife's point of view. For the most part, nothing eats it, although I once saw sparrows feeding on the seeds in late summer.
Loosestrife can also encroach on drier crop fields and pastures where it becomes a more direct economic issue. Each mature plant can produce up to 2.7 million seeds in one growing season. The rootstock also sends out 30 to 50 shoots that create a dense, monocultural web underground. This effectively chokes out "competing" vegetation.
On this side of the Atlantic, there are no natural controls for Purple Loosestrife. Our wildlife does not eat it or use it for breeding habitat. In Europe, over 100 insects feed on various parts of the plant. From these, five beetle species were selected and introduced into this country under controlled (caged) conditions. Some of the testing was done at Montezuma National Wildlife Refuge near the visitor's center east of Seneca Falls, NY. After determining that these beetles posed no threat to our desirable vegetation, they were released into the wild. Two of the insects feed on the leaves and new shoots; these are the kind released at Montezuma. A third beetle, a type of weevil, bores through the roots. The last two species eat the flowers. Some of the beetles were also released at Blue Cut Nature Center between Newark and Lyons in Wayne County, NY.
While these natural insect controls spread and multiply, a number of other steps need to be taken. So-called "sterile" varieties of garden loosestrife have been shown to cross-pollinate with wild Purple Loosestrife and produce viable seeds. Gardeners are asked to avoid planting loosestrife or any of its 26 cultivars. If it already grows in your garden, cut off the flower spikes as soon as the petals begin to drop and dispose of them in a plastic bag. Incineration is effective, but generally prohibited. If you are planting wildflowers, check the seed mix packets and make sure there is no loosestrife. Small infestations of loosestrife can be controlled by digging and hand pulling. Larger patches can be controlled by constant cutting. Chemical control usually requires a permit because of the danger to wetlands. Check with the Department of Environmental Conservation if you live in New York State or the state agency where you live.
In areas where loosestrife has already taken over a marsh, the best we can probably do for now is admire the beautiful color and wait for the beetles to arrive.
Contact Dave at northeastnaturalist@yahoo.com
(This copyrighted article and photo first appeared in The Times of Wayne County, July 28, 2008. All rights reserved.)

Wednesday, July 23, 2008

Least Sandpipers

This blog has been revised and reposted with additional photos on September 6, 2012.
http://northeastnaturalist.blogspot.com/2012/09/least-mudpiper.html

Thursday, July 10, 2008

Little Red Bugs






















 
 
 
Little Red Bugs - © Dave Spier

Do you have little red bugs in your yard? Multiple clusters of 10 to 20 or so, hundreds all together, are crawling around the maple leaves that blew up against our garden fence last fall. I left the dead leaves there as mulch to control the weeds. Among the leaves are skeletonized maple seeds and the tiny bugs seem to be sucking some sort of nourishment from the seemingly dead and dried samaras (the botanical name for these winged seeds).

Closer examination of these insects with red abdomens (actually red with some bright-orange markings) reveals darker wing pads beginning to grow backwards from the shoulders. Small heads look back at me through dull red eyes. Long antennae could be mistaken for a fourth pair of legs. These are the nymphs of the Eastern Boxelder Bug, Boisea trivittata, (syn. Leptocoris trivittatus), a member of the Order Hemiptera, or True Bugs. After several more molts, each successively larger, the immature nymphs will transform into flying adults about a half-inch long. Most of the red color is lost, save for a few red edges on the forewings and three red lines on the thorax just behind the head. They are named for their favorite food, the seeds of Boxelder trees, also known as ash-leaved maples, a reference to the compound, opposite leaves reminiscent of the unrelated ash tree. Perhaps they can't tell the difference because Boxelder Bugs sometimes also feed on ash and, occasionally, a variety of other plants and fruits.

In the fall, adult Boxelder Bugs become a nuisance by inviting themselves into the warm, cozy interiors of our homes. The first sign of trouble may be swarms of the bugs on sunny exterior walls. From there they find tiny cracks through siding or past windows and under doors. The good news is they do not sting, transmit disease, damage structures, destroy fabrics, infest food or carry filth. When spring arrives, they leave in order to lay their eggs on Boxelder trees or other suitable venues which seem to have included the maple-leaf litter along my fence, although I do have a Boxelder tree on the northeast corner of the property some distance from the fence, and fortunately far from the house. Incubation of the eggs takes about two weeks and then "voila!" Swarms of little red bugs begin milling about.

In early July, we were also dealing with Squash Bugs, Squash Vine Borers, Three-lined Potato Beetles, White Cabbage Butterflies and Japanese Beetles as well as deer (I'm guessing) eating broccoli leaves. So far, the garden fence is rabbit and woodchuck proof and I think we found a good deer repellent now.
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photo notes: exposure was 1/200 sec. at f/13 using the Canon MP-E 65mm (1-5x, but actual magnification not recorded) with twin macro flash on a digital Rebel (6 mp)
 

This was written from a New York perspective (specifically the northern Finger Lakes region). Corrections, comments and questions are always welcome at northeastnaturalist@yahoo.com or connect through my Facebook page and photo page. There's also a community-type page for The Northeast Naturalist. Other nature and geology topics can be found on the parallel blogs Adirondack Naturalist and Heading Out.
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(The original copyrighted article and photo [taken June 29] first appeared in the Times of Wayne County, July 7, 2008. All rights reserved.)

Tuesday, June 3, 2008

Invasion

This article, with slight revisions, has been reposted at http://northeastnaturalist.blogspot.com/2013/04/invasion.html
(The original copyrighted article and photo were first published in the Times of Wayne County, May 19, 2008. All rights reserved.)