Cedar Waxwing US FWS FWS Digital Library, David Menke, PhotographerEvery winter, many of Utah’s breeding birds migrate south to avoid the cold. After the warblers, tanagers, and orioles leave each fall, we share the snowy winter with hardier residents, such as chickadees, nuthatches, and juncos. But even hardier birds breed in the far north and venture south to Utah only during the most severe winters.
Many people are familiar with the high, thin calls of Cedar Wawings. Less frequently heard in Utah are the slightly lower calls of their close cousins, Bohemian Waxwings.
Bohemian Waxwing, licensed under the Creative Commons Attribution-Share Alike 2.0 Generic license. Source Wikimedia.org, Randen Pederson, Photographer.Bohemian Waxwings are slightly larger than Cedar Waxwings, and a little fancier—their wing feathers include red, yellow, black, and white, and the underside of their tails is a rich cinnamon. Both species gather by the hundreds to eat berries, so you won’t miss a flock if there’s one nearby. Although waxwings are songbirds, the calls you hear don’t serve the same functions as true songs, advertising mate quality and defending territories. Instead, waxwings cooperate to find and feed on scattered fruit, their main winter diet. Unlike most birds, waxwings are able to smell, which may help them find their food. If waxwings eat berries that have begun to ferment over the winter months, they may become intoxicated even though their ability to metabolize ethanol is very high. The last time Bohemian Waxwings were abundant in Utah was during the winter of 2012-2013.
Biking daily from Smithfield Canyon to USU campus, combined with an early am run, I’m well aware of the drop in temperatures, as are those of us who find themselves outdoors on a more permanent schedule. I’m speaking of our relatives who reside in the wild- birds, trees, raccoons, and such.
While I put on an extra layer or two, plants and animals have far more sophisticated adaptations from behavioral to physiological to structural.
We are all aware of the marvelous migration and hibernation behaviors, so let’s add a few more amazing adaptations to the list.
I’ll begin with a bird that is very common at our winter feeder- the Dark-eyed Junco. which responds to the first shortening days of summer with a series of physical changes: its reproductive organs become inactive and shrink in size, hormones stimulate the rapid growth of a new set of feathers, and fat deposits develop to provide fuel for the long migratory flight ahead.
Thus the preparation for migration starts as soon as the days begin to shorten. And the process must operate in reverse when the bird is in its winter habitat in the United States. As soon as days begin to lengthen, the Dark-eyed Junco must gear up physically for the flight north and breeding season. If it fails to do so, it likely won’t survive a long-distance migration. So the cycle of life and its related migrations and transitions are deeply connected to the heavens.
Plants are no less amazing. Those in temperate zones must also set their calendars accurately in order to flower and, for deciduous species, develop and drop leaves at the optimal time. Plants set their internal calendars using several attributes from the sunlight they receive. In fact, the angle of the sun may be more important to a plant than day length.
That’s because plant cells produce compounds called phytochromes in response to different portions of the light spectrum. Direct sunlight is higher in red light, while indirect sunlight contains more far-red light. During late fall and early winter, when the sun remains low in the southern sky, the indirect light produces an increase in far-red phytochromes.
As spring approaches and the arc of the sun rises in the sky, direct sunlight triggers the production of red phytochromes. The ratio of these two compounds mediates the hormones involved in flowering, leaf drop, and bud development. Even seeds below the soil are affected. The amount of red and far-red light that penetrate the soil is sufficient to govern germination.
Some behavioral alterations worth mention beyond migrating and hibernation are herding and flocking, huddling to share body warmth, dietary change, hair & feather change- both color and structure, and many more but my radio time is ending, so now it’s your turn to explore more! It really does make you appreciated the wonders of nature.
This is Jack Greene for Wild About Utah.
Credits:
Image: Courtesy and copyright 2008 Ryan P. O’Donnell
Text: Jack Greene, Bridgerland Audubon Society
Skier at Brian Head Photo Courtesy USDA Forest Service
As the mountains begin to take on hues of scarlet, gold and russet, many Utahns might be looking eagerly toward the coming months when those slopes will be blanketed in white. The Utah ski industry nurtures a whopping annual income of about $800 million dollars. It’s no surprise, therefore, that the state claims to have the “greatest snow on earth.” In fact, the state of Utah managed to make their slogan a federal trademark in 1995 after winning a lawsuit brought by the Ringling Brothers and Barnum & Bailey circus group, who felt the catchy marketing phrase might be confused with their slogan, the Greatest Show on Earth.
The trademark must have worked, because Utah draws so many visitors to its slopes, it racks up about 4 million skier days annually. But disregard plenty of evidence that we do indeed draw a crowd, and the statement is pretty subjective. So what’s the science behind our legendary powder?
The ideal condition skiers hope for is a deep, fluffy snow that creates the illusion of bottomless powder. And finding it is a bit like the Goldilocks story. Too wet, and you bog down. Too dry, and there’s not enough body to create a floating sensation beneath the ski. If the terrain is too steep, the powder won’t stick. And if it’s not steep enough, you can’t build sufficient momentum to glide over the top.
To get to the bottom of why Utah’s snow is just right, we actually have to look even further westward, toward the slow warm waters of the North Pacific current. As water laden clouds move inland, snow first falls over the Cascades in the north and the Sierra Nevadas further south, with an average moisture content of 12%. Even in areas like Washington’s Mt. Baker, where annual snowfall comes in greater quantities than Utah, the moister maritime snow creates a heavy base that bogs down skis. By the time these winter storms cross the Great Basin and reach the skiers’ Mecca of Alta and the Wasatch Range, the moisture content will have decreased to about 8.5%. And that seems to be the sweet spot. The moisture content of Utah’s intermountain snow is just enough that powder from our first storms settles into a soft but voluminous base. As winter progresses, fresh snow falls in a cold and mostly arid environment, forming very fine, symmetrical crystals called dendrites. The microscopic structure of dendrites allows them to accumulate in well ventilated, incompact drifts, much like the puffy down in your favorite pillow or ski jacket.
And perfect powder isn’t the only advantage Utah’s ski resorts have over their neighbors. Our mountainous topography, with its wealth of winding canyons, means we have an abundance of slopes well protected from strong winds which could compact or carry away fresh snowfall. And while so many cold and overcast days might get you down, it also protects our top powder from radiation and air mass effect, which can create a crust along the surface. And that means our freshly fallen powder sticks around for longer.
So consider that Utah offers 26,000 acres of mountain, blanketed in more than 500 annual inches of perfect intermountain snow, and it’s no wonder we enjoy 5 times the number of “powder days” as our neighbors. “The Greatest Snow on Earth” starts sounding a lot less subjective, and more like truth. In fact, you just might be tempted to make like Goldilocks and make yourself at home.
For Wild About Utah and Stokes Nature Center, I’m Ru Mahoney.
Credits:
Image: Courtesy USDA Forest Service, fs.usda.gov
Text: Ru Mahoney, Stokes Nature Center in Logan Canyon.
I love the four seasons. Having spent my 72 years residing in the mid latitudes, I’ve learned to celebrate each of our seasons, but especially spring!
This is the rebirth flush with abundant water, new greenery, and air filled with bird song and sweet aromas as new flowers perfume the air hoping to lure in a pollinator.
With mid-April upon us and our 42 degree latitude, spring is in full swing here in northern Utah! Winter departs grudgingly slapping us with snow squalls intermingled with glorious, early summer days, a wild roller coaster ride which I truly enjoy!
I’m an avid phenology follower. Phenology is the study of how life adapts to seasonal changes. I revel in the first floral bloom, the first neotropical birds returning from Latin America with a heart full of song, and newly emerged, gaudy butterflies.
With a relatively stable climate, until recently, the timing of these events has evolved to near perfection
Let’s take a closer look at some of these phenomena. I’ll begin with our neotropical birds such as lazuli buntings, yellow warblers, and Western tanagers to mention a few. These species spend over half of their year in Mexico, Central and South America flying thousands of miles to for the breeding and nesting season in the Intermountain West. This may seem a bit extreme for these tiny flurries of life.
On closer inspection, you will find they have good reason for this daunting and dangerous task. The tropics have a relatively stable climate without the dramatic seasonal change that we experience. This results in relatively stable populations of flowers and insects, the primary food sources for most species. Further, the ratio of daylight to darkness is nearly constant with 12 hours of each. Our days lengthen as we journey toward summer solstice with nearly 16 hours of daylight! This allows a burst of energy to flow through ecosystems resulting in eruptive populations of insects and floral bloom. It also offers long hours of daylight for parents to gather food for their young which grow rapidly toward fledglings, thus reducing the possibility of predation and also preparing them for the arduous flight south as fall approaches.
Let’s examine flowers and insects. With our very warm winter and spring, I was expecting a much earlier arrival of both and was not disappointed. I counted 17 species of flowers by the second week of April! And butterflies were on a similar schedule with 9 different species during the last week of March- remarkably early! Although delighted, it occurred to me that returning birds may not be so pleased. If the flowers begin to fade, and insects begin their downward slide at the peak of birds rearing their young, trouble is afoot! A five year Audubon study revealed that 1/3 of our birds are predicted to be severely impacted by these rapid climate shifts.
On a more positive note, spring will continue as will bird song, vernal waterfalls, eruptions of wildflowers and butterflies. And spring repeats itself as we move to higher elevations. As cornices on our mountain ridges recede, up pops flowers for yet another spring bloom, and with them butterflies, bees, and birds!
