Spring Has Sprung!
March is the absolute high point in anyone’s life who anticipates and celebrates the annual celebration of the arrival of spring. For this reason, it is the first chapter in my book “Naturally Curious” – every day brings confirmation that no matter what is going on in the human world, you can depend on the natural world to observe the rites of spring.
Mourning Cloak butterflies emerge from behind loose bark, migrating American Woodcock probe the mud, sleepy Eastern Chipmunks appear above ground, Red-winged Blackbirds return, Beavers see the sun for the first time in perhaps months, buds swell with newly accessible sap, Red Fox kits emerge from dens, Wild Turkeys mate, Spring Peepers peep, Painted Turtles emerge from hibernation and bask in the sun, Ruffed Grouse drum and Skunk Cabbage blooms.
For at least a few minutes a day, we can lose ourselves in the natural rhythm of life that surrounds us.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Winter Adaptations of the Ruffed Grouse
Ruffed Grouse have both behavioral (diving into the snow on cold nights) and physical strategies for dealing with the cold, snow and ice of New England winters. Three of the physical changes that take place in the fall are evident by looking closely at a grouse’s legs, feet and beak. The feathers on its legs grow thicker and further down towards its feet, to provide better insulation. Small comb-like growths of skin, called pectinations, develop along either side of each toe. These increase the surface area of a grouse’s foot, and serve as snowshoes in deep snow. They also help the grouse cling to icy branches while it quickly snips off poplar and other buds at either end of the day. And on its beak, feathers expand downward to cover its nostrils, slowing the cold air and giving it a chance to warm up before it is inhaled by the grouse.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Spruce Grouse Foraging
While Ruffed Grouse are plentiful throughout most of New England, one has to go to northern Vermont, New Hampshire or Maine to see its cousin, the Spruce Grouse. Associated with boreal forests, this largely herbivorous bird feeds primarily on the needles of pine, spruce and fir (a small amount of animal matter is consumed in the summer as well as ground vegetation). Especially in the winter, a large volume of conifer browse is consumed in order to meet energy demands.
The grouse holds the needle between the tips of its mandibles and breaks it off by flicking its head. This action, and the fact that Spruce Grouse feed exclusively on needles in the winter, leads to the wearing off of the tip of the bird’s upper mandible by spring.
If you are searching for a Spruce Grouse, you might want to concentrate in the middle of the crowns of trees, as this is where the birds tend to forage. Theories for this preference include the fact that needles in this location have higher nutritive value, branches provide sturdy support, and grouse can see approaching avian predators while remaining partially concealed. (Birds of North America, Cornell Lab of Ornithology). (Photo: male Spruce Grouse browsing on Tamarack needles and (inset) looking for grit on the ground.)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Red Elderberry Attracts Wildlife Year Round
The pollinated and fertilized white flowers of Red Elderberry (Sambucus racemosa) have recently developed into the red fruit for which this plant is named. Many people are familiar with its relative, Common Elderberry (S. canadensis), which produces dark purple fruit that is used to make jams, jellies, pies and elderberry wine. While Red Elderberry fruit can be used to make all of these, its raw berries are toxic. Red Elderberry’s popularity is greatest with pollinators, birds and four-footed mammals.
The cyanide-producing toxins in its flowers, (raw) fruit, stems, bark, leaves and roots do not seem to discourage wildlife’s attraction to Red Elderberry. The odor of its flowers, its nectar, and its highly nutritious pollen attract many ants, bees, wasps and flies. At least 50 species of songbirds eat the bright red fruits, including red-eyed vireos, ruffed grouse, song sparrows, gray catbirds, brown thrashers, and thrushes. Squirrels, mice, raccoons, and black bears also eat the fruit. Porcupines, mice and snowshoe hares eat the buds and bark in winter. The foliage is usually avoided by herbivores, although white-tailed deer and moose browse on it occasionally.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Eat And Run Strategy
Ruffed grouse, white-tailed deer and moose, all prey species and all plant eaters, share certain characteristics that have to do with food consumption and digestion. They all tend to eat large quantities rather quickly in one spot, and then move to another, safer, spot to digest their food. This technique minimizes the amount of time that they are likely to be out in the open and focused more on eating than on predators. Eating quickly and storing the consumed food in a chamber and digesting it later at their leisure, under cover, makes a lot of sense.
All three animals have a multi-chambered stomach and microorganisms efficient at breaking down cellulose and extracting nutrients from plants. After browsing on branches and buds, deer and moose seek shelter where they then regurgitate and chew their cud. Grouse do not linger over their meals – 20 minutes of foraging will sustain them all day. Leaves, buds and twigs are stored in their crop (a wide portion of the esophagus) until the grouse seeks shelter, where the food eventually reaches their gizzard. Here, with the aid of gravel, it is ground up.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Pectination Growth Started
Every fall Ruffed Grouse (Bonasa umbellus) grow skin-like fringes called pectinations on either side of each toe. They serve as snowshoes, helping grouse stay on top of the snow when walking, as well as cling to icy branches while eating the buds of poplars and other trees in the winter. In the spring grouse shed these adaptive fringes.
Ornithological texts describe these growths as appearing in the fall, but usually do not specify exactly when they develop. A recent look at a road-killed grouse’s foot (photo) showed that pectinations have begun to develop, but have not completed their growth. The pectinations shown here will double their length by the time snow flies.
Ruffed Grouse Snow Roosting
I recently had an experience while snowshoeing which I have always hoped to have, but which has escaped me during all these years of tromping through the woods. I was following the tracks of a Ruffed Grouse and all of a sudden it exploded out of the snow about two feet in front of me as it left its night time shelter. Now that we have over ten inches of fluffy snow, grouse can dive into the snow and spend the night in their self-made snow roosts. Finding a grouse’s snow roost is a relatively common experience; being startled by a grouse exiting one is not.
Diving head first into the snow, the grouse works its way anywhere from three to ten feet, creating a 4-inch-wide tunnel through the snow before it hollows out a small cavity and settles down for the night in its own little igloo. Up until recently, a hard crust prevented grouse from seeking shelter this winter in this manner. Had temperatures been very cold, many grouse would have suffered and even perished under these conditions. Fortunately, they can now roost in the snow, where temperatures are much warmer (as high as 32°F.), and rarely fall below 20°F. regardless of how cold it gets outside. Not only do these roosts hide the occupants from predators, but they provide an energy savings of 30 percent or more for grouse.
(Photo: Snow roost entrance hole (nearest the bottom of photo) where a grouse dove into the snow, and the exit hole (nearest top of photo), three feet from entrance hole, which a Ruffed Grouse created when it exploded out of its roost. If you look closely at the exit hole, you may be able to detect wing marks.)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
The Relationship Between Ruffed Grouse & Poplars In Winter
Poplar (also called Aspen) buds are an important winter food source for wildlife, but for none as much as the Ruffed Grouse. During the course of a year, a Ruffed Grouse may feed from as many as 100 species of plants, but in the winter, species of poplar are by far its most important food source. In fact, the relationship between grouse and poplars is such that the range of the Ruffed Grouse is practically identical to the range of Trembling (also known as Quaking) Aspen (Populus tremuloides) and Big-tooth Aspen (Populus grandidentata).
Poplars are dioecious – the male and female flowers grow on separate trees. Although grouse will settle for any poplar bud, it is the male flower buds of Trembling Aspen trees which they prefer, due to the buds’ high amounts of proteins, fats and minerals. (Female buds are smaller and have less nutrients, oddly enough.) Ruffed Grouse seldom feed on a poplar tree that is less than 30 years old. Perhaps these older trees have more vigorous buds, or perhaps their branches are easier to perch on because they are larger. (Information source: Ruffed Grouse: Woodland Drummer by Michael Furtman)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
1-13-1
Ruffed Grouse Drumming
A majority of male passerines, or perching birds (also called songbirds) claim territories and secure mates through song. With the help of a syrinx, or voice box, musical notes, some more complex than others, are created. There are species of birds in different orders that use other parts of their bodies for territorial and courtship displays, among them ruffed grouse (wings), American woodcock (wings) and Wilson’s snipe (tail).
Male ruffed grouse, also known as partridge, are aggressively territorial throughout their adult lives, defending roughly 6-10 acres of woodland which is usually shared with one or two hens. The male grouse claims his property by engaging in a “drumming” display during which he creates a sound reminiscent of a lawn mower starting up. This sound is made by the male beating his wings against the air to create a vacuum, as lightning does when it makes thunder. The drummer usually stands on a log, stone or mound of dirt roughly 10-12 inches above the ground when drumming and this substrate is called a “drumming log.” He does not strike the log to make the noise, he only uses the drumming log as a stage for his display.
Grouse occasionally drum in the summer and fall, but in the spring, drumming becomes more frequent and prolonged as the male advertises his location to hens seeking a mate. This phenomenon is heard but rarely seen by humans; Lang Elliott has captured both the sight and sound of a ruffed grouse drumming in this extraordinary video: http://langelliott.com/mary-holland/ruffed-grouse/ (Sound recording © Lang Elliott – langelliott.com)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse Unable To Seek Refuge in Snow Caves
Unlike much of the Northeast, central Vermont has only a few inches of snow on the ground. These conditions can affect all forms of predators and prey both negatively and positively, from exposed mice and voles to easily-satiated hawks and owls. In the case of Ruffed Grouse, which seek shelter on cold winter nights by diving into the snow, less than 10 inches of snow can spell disaster. In their snow caves they are hidden from view and well insulated (where it rarely drops below 20°F.). A lack of snow can be life-threatening for grouse if the temperature drops too low for too long. Unable to create a sheltered cavity in the snow, Ruffed Grouse bed down on top of it, often close to the base of a tree where there may be some shelter from the wind. Fortunately, most nights have not been extremely cold thus far this winter.
After the grouse departs in the morning, you often find scat where it bedded down. Grouse scat comes in two forms, one a dry, fibrous cylindrical pellet with a white-wash of uric acid at one end, and the other a softer, darker brown plop. The vast majority of a grouse’s diet (buds, twigs, leaves, catkins) goes directly through its digestive system and forms the dry, courser scat. Finer (and more nutritious) material such as the cambium layer of woody plants enters the caeca, two specialized pouches, before passing through the large intestine. The caeca contain bacteria which break down cellulose and produce the more digested, and therefore more liquefied, scat (see foreground in photo).
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse Flying Into Windows
Those of us who feed birds are well aware of the hazards that windows and glass doors present to birds. The latest research shows that roughly 988 million birds are killed each year in the United States from hitting windows. Migratory birds and songbirds are the most common victims, but Ruffed Grouse, especially in the fall and winter, are very apt to collide with glass windows. (This phenomenon is not the same as the aggressive behavior towards glass that a bird’s reflection can promote, especially by males during the breeding season.)
Many of the grouse victims are first-year birds. Often, inexperienced young grouse, frightened by a predator, crash into buildings, trees or windows in a so-called “crazy-flight.” Hard, transparent glass is not something grouse recognize as a barrier, due to the reflections it creates. There are a number of things one can do to reduce the chances of this happening. Netting, decals, window film and tape hanging from the top of the window can help. One of many creative new products available are window panes that have external patterns that birds can see from the outside, but that are invisible from the inside. On a national level, legislation and bird-friendly buildings are gaining traction. For more window crash-prevention ideas, go to http://www.birdwatchingdaily.com/featured-stories/15-products-that-prevent-windows-strikes/. (Photo by Eve Bernhard)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
The Short Life Span of Ruffed Grouse
Ruffed grouse typically have a short life span; few live to be three years old. By mid-August about 60 percent of the grouse hatched that year are lost to predators, weather extremes, disease, accidents (such as flying into windows) and hunters. Less than half of the surviving young survive through the winter to have a chance to breed in the spring, and less than half of those that survive long enough to breed make it to a second mating season. The hazards for a ruffed grouse are many, with predation at the top of the list.
Birds of prey, especially the goshawk and great horned owl, take many grouse, but terrestrial hunters such as foxes, coyotes, bobcats and fishers also take advantage of this plentiful food source. Along with hares, porcupines, squirrels, mice and voles, grouse are one of the fisher’s preferred foods. A fisher managed to capture a ruffed grouse in the pictured scene, leaving only tracks and a few tell-tale feathers to tell the story.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Common Polypody Spores Dispersing
Common polypody (Polypodium virginianum), also called Rock Cap Fern, is a perennial plant found most often growing on rock surfaces usually in moist, shady woods. Being a fern, Common Polypody reproduces by spores. Structures that produce and contain spores (sporangia) are found on the undersides of the fertile frond leaflets. The sporangia form round clusters called sori. The sori of Common Polypody are orange-brown when mature and lack the protective covering (indusium) that some other fern species have. At this time of year, the mature spores are being dispersed by the wind.
The ability of Common Polypody to tolerate extreme desiccation (the leaves roll up when moisture isn’t as available, and resume their normal state when moist conditions return) means it is well adapted to the extreme moisture fluctuations of rock surfaces. Its evergreen fronds are consumed in the winter by Ruffed Grouse, Wild Turkey, and White-tailed Deer.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse Make Do With Shallow Soft Snow Depth
There are about five or six inches of new powdery snow on top of an icy crust in parts of central Vermont now, with more to come soon. It is common knowledge that ten inches of snow are necessary for Ruffed Grouse to dive into and burrow under the snow in order to make an insulating nocturnal snow roost. With only five inches of snow, a grouse still seeks shelter, but somehow it knows not to dive into the snow from the air. Rather, it lands on the surface of the snow, and then walks along making a groove in the snow as it goes, until it decides to rest for the night.
Several such resting spots were apparent today at the base of trees — slight depressions fully exposed. The grouse that made the snow roost in this photograph shuffled through the snow and then scrunched down without breaking the surface of the snow where it settled for the night, so that it had an inch or two of snow over its body – hiding it from predators, if not providing much insulation. In the morning, after defecating, it departed, not bursting out of a snow bank as it would if there were a lot of snow, but instead lifting off in plain view, leaving faint wing prints on the surface of the snow.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
The Effects of An Icy Crust on Wildlife
This winter has brought us several storms that have ended in rain and were followed by plummeting temperatures. Just a few inches down into the powdery snow on top of the ground there is a ¼”-thick crust, and if you dig down several more inches, there is a second layer of ice, roughly 1/8”-thick. When a thick, icy layer of crust forms, it can have a dramatic effect on the lives of wildlife both above and below it.
Some animals are relatively unaffected by the presence of a crust but many predators and prey are significantly helped or hindered by it. Ruffed grouse cannot seek overnight shelter from the bitter cold and/or predators by diving into a foot of soft snow and creating a snow cave (see photo). On the other hand, small rodents have a distinct advantage — mice and voles have several layers of ice between themselves and hungry coyotes, foxes and owls. Snowshoe hares lose the advantage they usually have on deep, soft snow — “snowshoes” that keep them on top of the snow when the bobcat or fisher chasing them has to flounder through it. Turkeys don’t have the strength to dig down through one thick crust, much less two or more, in order to reach hidden acorns. If a deer is being chased, its pointed hooves will break through the crust, slowing the deer down, whereas the crust may well support a lighter predator, allowing it to outrun the deer. Red squirrels have to work much harder to reach their cached winter cones and to create tunnels.
What is a mere inconvenience to us humans literally is costing as well as saving the lives of wildlife this winter.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Sedge Seeds
Over 500 species of sedges in the genus Carex are found in the U.S. – over half of the world’s total. The great majority of these perennial, grass-like plants grow in the moist soil of meadows, marshes and bogs, as well as in high altitudes. Sedges are often distinguished from grasses by their stem, which is typically triangular in cross-section (“sedges have edges”). The flowers of sedges, each surrounded by a bottle-shaped bract, or modified leaf called a perigynium, are clustered on spikelets. The tips of these bracts persist after the seeds have formed, giving the spikelets a prickly appearance.
Because of their wide availability, the seeds are eaten by many kinds of wildlife, especially birds. Wild Turkeys, American Woodcock, Northern Cardinals, Horned Larks, Snow Buntings, Lapland Longspurs, ducks, rails, sparrows, redpolls and finches relish them. In the Northeast, Carex seeds, along with insects, are the most regular items in the diet of Ruffed Grouse chicks. Moose also occasionally feed on sedge seeds. (Photo: Longhair or Bottlebrush Sedge, Carex comosa)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse Nostril Feathers
Ruffed Grouse have adapted to cold winter months in a number of ways, from growing “snowshoe” pectinations on their toes to having their legs covered with fine feathers. Equally effective are the feathers covering a grouse’s nostrils, which are thought to heat cold air as the bird breathes in. (Thanks to Sara and Warren Demont for photo op.)
Ruffed Grouse Preening
Birds have up to 25,000 feathers, and most birds preen, or clean, waterproof and align their feathers, several times a day. Ruffed grouse, as well as most other birds, possess an uropygial gland, or preen gland, on their rump. (Some types of birds, including owls, pigeons, parrots and hawks, lack an uropygial gland and instead have specialized feathers that disintegrate into powder down, which serves the same purpose as preen oil.) The preen gland produces a waxy substance that helps waterproof feathers and keeps them flexible.
Ruffed grouse reach back and rub their beaks on this gland, and then distribute the wax on their body and wing feathers by stroking them toward the tip. The grouse grasps a feather near the base and draws it through the partly close beak, nibbling as it goes. This distributes the wax and cleans parasites from the feathers. In order to preen its head, the grouse must rub it on other parts of its body. Preening is usually done in a fairly open setting but with a degree of overhead protection, so that the grouse can watch for terrestrial predators, while being protected from hawks and owls.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse on Nests
A Ruffed Grouse’s nest is pretty basic – just a shallow bowl on the forest floor, created by the hen grouse tossing leaves over her shoulder and having them fall on her back, slip down to the ground and form a bowl. Ruffed Grouse lay anywhere from 9 to 14 eggs at intervals of 25 to 30 hours, which means it takes about two weeks for a hen to lay an average clutch of 11 eggs. Each of her eggs weighs about 4 percent of her body weight — the entire clutch will be equal to about half of her weight. Once incubation starts (when the last egg is laid) the hen’s behavior goes from wandering around and feeding voraciously, to sitting on the nest and barely moving. Because of this behavior, as well as her cryptic coloration, an incubating Ruffed Grouse hen is much more likely to see you before you see her. She will stay motionless on her nest, even in the face of danger, hiding her eggs. Once she is certain she has been spotted, she will fly off the nest, exposing her eggs. Foxes, crows, ravens, chipmunks, skunks, bobcats and raccoons are some of the predators responsible for the loss of 25% – 40% of grouse nests each year. After the precocial Ruffed Grouse chicks hatch during the first two weeks of June, they will be led away from the nest site by the hen. Within 24 hours they will be feeding on insects and within a week they may double their weight! (Thanks to Ginny Barlow for photo op.)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse Wings
You can often determine the type of flight that a bird is capable of by looking at the shape of its wings. Long, narrow wings are excellent for gliding, while the short, rounded wings of a Ruffed Grouse allow for tight maneuvering in the dense forests where they live. The shape of their wings and their quick-contracting muscles equip grouse for the short bursts of high speed (not long distances) they take when feeding or evading predators. (Photo: a Ruffed Grouse walked a short way and then took flight, beating its wings against the snow twice before it was airborne.)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Ruffed Grouse Snow Cave
When snow depth is over 10” Ruffed Grouse are known to dive into it and often burrow a short distance in order to seek refuge from the wind and the cold as well as from predators, a behavior known as “snow roosting.” Because the grouse flies into the snow leaving no tracks and little scent, predators have difficulty detecting them. The major risk is freezing rain which can form a crust on top of the snow, trapping the grouse. The Ruffed Grouse’s behavior allows it to conserve a great deal of energy, as the temperature inside this roost rarely falls beneath 20°F. This conservation of energy translates into less time spent up in trees eating buds, exposed to hawks and other predators. When morning comes, the grouse usually bursts out of the snow, leaving a hole and wing marks, or, as in this case, shuffles its way to the surface of the snow before taking off. The presence of scat indicates that the left-hand cavity in this photograph is where the bird bedded down and its exit was made to the right. (Thanks to Edith Hoose for photo op.)
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Northern Hawk Owl
The Northern Hawk Owl is a bird of the remote Alaskan and Canadian boreal forests. Its name reflects the fact that this diurnal owl has both the appearance and behavior of a hawk, specifically, an accipiter. Although the Northern Hawk Owl winters throughout its breeding range, it periodically erupts southward into southern Canada and the northern United States. Sightings of this bird are rare in Vermont, but in recent winters, including the current one, there have been some. As with Snowy Owls, the magnitude and extent of these winter irruptions are thought to correlate with high reproductive success followed by severe winter conditions and decreased prey availability, but much remains to be understood about their winter dispersal habits. What we do know is that the Northern Hawk Owl’s skills as a hunter are very impressive. It can detect prey (small rodents, grouse, hares) by sight at a distance of half a mile and just using its ears can find prey under a foot of snow.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.
Naturally Curious with Mary Holland 
What Other Naturally Curious People Are Saying