Feast or famine for animals in the winter

Last weekend, the chickadees and nuthatches finally found the two bird feeders I filled several weeks ago. For birds, finding a full feeder is like finding a Thanksgiving feast. 

Surviving winter is feast or famine for animals that don’t migrate or hibernate. Plentiful insects, fruits and green vegetation are gone or hard to find. Once an animal finds a feast, it will frequently come back, eat it all at once or cache it away for times of famine. 

The chickadees and nuthatches don’t stay at my feeder all day, but come in waves. They make their rounds between known food sources--maybe even the neighbor’s bird feeders. Before they found my feeders, they fed on the cones in the Douglas-fir trees in the yard every morning. 

Some flocks of birds feed almost exclusively on seed crops in the winter which makes their movements highly irregular. Redpolls and goldfinches fly between birch stands to feed on small birch seeds. Flocks of crossbills seek out spruce and pine trees to feast on the seeds that their bills are specifically adapted to pry out of the cones.

Flock of pine grosbeaks on cone-laden tree

Hemlocks are the tree of choice for pine siskins whose long, thin bills reach under the bracts of hemlock cones. Waxwings travel in flocks and descend upon berry-laden trees or shrubs and feast until every last berry is gone. 

Birds such as waxwings, redpolls and grosbeaks will fly out of their typical range in search of seeds or berries if there is a crop failure in their regular range--which is one way to avoid famine in the winter. 

Gray Jay

Another way animals avoid famine is to cache food when it is abundant. Only a small percentage of species worldwide cache food for winter. Gray jays cache food all year long by wadding food into a ball, coating it with saliva and wedging it under tree bark. As long as they cache enough food, their excellent memory prevents them from famine in the winter. 

Living in mountain talus slopes, the resourceful pika makes hay in the summer by drying grasses and stockpiling it deep within the rocks where snow can’t reach it during the winter. 

Pika collecting vegetation to dry

Red squirrels are notorious for their caches of cones, called middens, scattered throughout the forest. Unlike the mushrooms that squirrels harvest and dry in the crotch of tree branches, they prefer to keep the cones moist. Dry cones are less palatable, so the cool, damp depths of middens are perfect for storing cones.

Squirrel midden

A few other rodents that stockpile seeds for winter are deer mice, pocket mice and chipmunks. A larger rodent, the beaver, stockpiles trees underwater to feast on all winter. 

Fewer animals stockpile meat for winter. Saw-whet and great horned owls create their own frozen dinners by killing and stockpiling mice. Then to eat a mouse, the owl sits on it like it is incubating an egg until the mouse is thawed enough to tear apart and eat. 

Then there are those animals that take advantage of other species caches to survive. Elk and deer feast on hay bales in fields and barns, turkeys feed on grain spilled next to grain bins, and birds feast on the cache of sunflower seeds hanging outside my window.

Note: Published in the Bonners Ferry Herald on Nov. 21, 2012. 

Leonid meteor shower peaks this weekend

Shooting stars are always exciting to see. Sometimes I only see them out of the corner of my eye, other times I’m lucky enough to be looking at the right part of the sky at the right time. 

Star trails with satellite crossing sky

Despite resemblance in brightness and size, shooting stars are not stars streaking through the sky but instead are meteors. Meteors have nothing to do with stars. Meteors are bits of interplanetary rock or debris that have fallen or broken off comets or asteroids and enter Earth’s atmosphere. Outside of Earth’s atmosphere, these rocks are called meteoroids.

Most meteors are smaller than a garden pea. Larger meteors do exist but they are less common. Meteors that are barely visible to the naked eye are usually only 0.55 millimeters in diameter--that’s smaller than a grain of rice!

When a meteor streaks across the sky, we aren’t seeing the meteor itself. We see the light emitted from reactions between the friction of the rapidly moving meteor with the gases in the atmosphere.   

Big Dipper

Meteoroids enter the atmosphere at tremendous speeds--between 25,000 to 160,000 miles per hour. They quickly ignite from searing friction with the atmosphere. The outer layer of the meteor is vaporized and stripped away due to high speed collisions with air molecules. 

The composition of a meteor and the colliding air molecules are responsible for a meteor’s color. Since the source of meteors varies, the elements within the rock or debris varies. When vaporized, each element emits a signature color. Meteors containing sodium will be orange-yellow, iron will be yellow, magnesium will be blue-green, nickel will be green, and ionized calcium will be violet. When a meteor appears red, the reactions of the atmospheric nitrogen and oxygen atoms are overpowering the reactions of the elements in the meteor. 

A meteor’s velocity can also impact its color and brightness. Slow meteors tend to be red or orange while fast meteors are frequently blue. Faster meteors are also brighter. 

Watching for meteors provides a chance to look at the stars

Most meteors only streak across the sky for a short time before they burn up in the atmosphere, typically between 60 to 80 miles above the Earth’s surface. If a meteor does make it to the Earth’s surface, it is called a meteorite. 

Interestingly, most meteorites tend to be from slow meteors. Nearly all meteorites originate from astroids but astroid-originated meteors only comprise five percent of the meteor population. The other 95 percent of meteors originate from comets and they rarely make it to the Earth’s surface. 

Meteoroids originating from astroids are created when something collides with the astroid and a piece is chipped off. These meteoroids typically create the sporadic meteors not associated with meteor showers. 

Comet-originated meteors are the ones seen during meteor showers. As a comet orbits around the sun, the heat from the sun causes the comet’s outer layer to vaporize and particles to “fall off” in the form of comet dust. 

Always a chance of seeing the unexpected

If the comet’s path crosses Earth’s orbit, then a meteor shower will occur when Earth passes through the comet dust every year. Since Earth encounters the comet dust at the same time every year, meteors seem to radiate from a specific constellation in the sky every time. Meteor showers receive their name by the constellation they radiate from. For example, the Leonid meteor shower radiates from the constellation Leo. 

November is when Earth passes through the comet dust that creates the Leonid meteor shower. The Leonid shower begins on Nov. 13 and ends on Nov. 21, with the peak around Nov. 17 or 18. At the peak, up to 10 meteors per hour will be visible. However, the Leonid meteor shower is cyclic like sunspots and has a cyclic peak every 33 years that is associated with the return of its parent comet into the inner solar system. During this cyclic peak, hundreds to thousands of meteors can be visible every hour--but that peak won’t be until around 2028. 

Note: Published in the Bonners Ferry Herald on Nov. 15, 2012. 

Sign Posts of the Forest

Wandering through the woods, I found a tree with claw marks scratched in the bark at eye-level and black hair stuck to once oozing sap. The culprit--most likely a black bear sometime this summer. 

Black bear claw marks and sapsucker holes

After I found the claw marks, I started to look for more animal sign on trees. On the same tree right next to the claw marks, were lines of square holes drilled into the bark--a sapsucker. True to their name, sapsuckers drill the holes to allow sap to ooze out so they can lap it up. 

Sapsuckers drill holes for sap

Sap is also the motive for black bears to peel the bark off the lower portion of trees, sometimes even girdling the tree. On the same wander in the woods, almost every larch tree for a few hundred yards had a section of bark removed from the base. Black bears go after the sweet tasting sap in spring and early summer and signs of their destruction last for the life of the tree. 

A black bear girdled this larch tree by peeling off the bark for the sap

Likewise, one single climb up an aspen tree by a black bear may be seen for the entire life of the tree since the claw marks scratched into the soft, smooth bark can become scabbed over. 

Aspen trees may also have rough, blackened trucks to the height an elk can reach. Elk like to gnaw on the aspen trees in winter, which causes the tree to scab over. 

Gnawing on trees, especially during the winter, is a habit on many animals and key to their survival. Porcupines gnaw large patches of bark off tree trunks and eat the bark off twigs. Their gnawed areas have neat edges, irregular outlines and numerous small toothmarks, which help distinguish them from elk or moose sign. 

Closer to the ground, snowshoe hares will feed on the bark of trees. However, when they feed on the cambium, they gnaw far beyond the bark into the woody center unlike other animals. 

Then there is the gnawing champion--the beaver--who gnaws through an entire tree trunk to fell a tree. In addition to eating the bark and wood, beavers need to constantly gnaw on trees to wear down their continuously growing teeth. 

Beaver sign

Instead of gnawing, woodpeckers drill into trees to find insects to eat or to excavate a nest cavity. Some of these sought after insects leave their own sign. Ever notice the insect trails on the inside of bark or the outer edge of wood when peeling the bark off for firewood? Birds will debark a section of tree to access these insects, such as bark beetles, and will expose the insect’s trails.

Woodpeckers hammered this tree for insects

Insect trails in wood

Some tree signs aren’t related to food. A medium-sized sapling with its bark shredded and small limbs broken reveals the presence of an elk or deer rubbing or thrashing its antlers on the tree during the rut. 

A deer rubbed the branches off this sapling

While not as obvious as elk or deer, bears will rub against a tree to remove their winter coat or unwanted parasites, often leaving behind hairs in sap or on bark. They need a back scratch too!

More animals than mentioned here let their presence be known, whether purposely or not, on sign posts in the forest. We even leave our sign on trees, in the form of trail blazes, so that we can find our way through the forest.  

Note: Published in the Bonners Ferry Herald on Nov. 8, 2012. 

Autumn reveals hidden hornet nests

As the yellow leaves of autumn drop from trees, they often reveal hidden treasures such as bird nests and less desirable wasp nests. The gray, papery football- to basketball-sized nests normally hidden by leaves are home to bald-faced hornets during the warmer months. Other paper wasps such as yellowjackets also create paper nests in varying shapes and sizes. Despite their name, bald-faced hornets are members of the yellowjacket family.

A bald-faced hornet nest that once was hidden by leaves

These visible nests in late fall and winter are the result of a summer’s worth of work by many hornets. The entire nest is built from wood fibers that each hornet has gathered, chewed and mixed with salvia in their mouth to form a soft wood pulp. The varying colors on the outside of the nest (called the envelope) result from different sources of wood fibers, which can include weathered and rotting wood, fence posts, dead plants, cardboard or newspaper. 

Varying colors a result of different sources of wood fibers

The queen bee initiates nest building by adhering wood pulp to a structure, such as a tree branch, that will hold the nest, typically at least three feet off the ground. Then the queen starts building the nest with a horizontal layer of hexagonal cells on the inside and a papery, protective envelope on the outside to the size of a golf ball. 

In those first cells, the queen will lay eggs that will become adult workers. Upon hatching and pupating into adults, the workers will take over the nest building and feeding the larvae while the queen solely lays more eggs in the cells they create. During the height of production a nest may hold up to 700 hornets. 

Inside of a hornet's nest

The workers keep building the nest one mouthful at a time until it is roughly football or basketball size. They will create several horizontal layers of cells on the inside and a one-to-two inch multi-layered envelope on the outside while leaving a small, round hole near the bottom for an entrance. 

Workers leave a small hole at the bottom for an entrance

Two sizes of hexagonal cells are created: small and large. The majority of the cells will be small and will be utilized up to three times during the summer to raise worker hornets. Starting in the fall, single-use larger cells will be constructed to raise the future queen hornets and the males (drones) that will mate with the newly hatched queens. 

Mated queen hornets are the only ones to overwinter--the remainder die off when the temperature drops below freezing, including the reigning queen. Despite the thick outer envelope on the nest that keeps the hornets warm in the spring and fall and cool in the summer, it isn’t enough protection for a new queen in the winter. Instead, she will spend the winter in a crevice under tree bark, in a tree stump, behind house siding or in the eaves of a house. Come spring, the new queen will begin her own nest since bald-faced hornets do not reuse nests. 

Bald-faced hornets still occupying a deteriorating nest in late autumn

The abandoned nests don’t go unused--spiders and other insects will seek shelter in the nests during winter. However, insect-seeking birds easily hone in on the exposed hornet nests dangling in bare trees and will readily shred the nests looking for slumbering insects, which truly makes the nests hidden treasures. 

Note: Published in the Bonners Ferry Herald on November 1, 2012. 

A great place to call home

Twilight was quickly fading as we drove south on Highway 95 after crossing the border at Eastport. As we descended down the hill by Brush Lake, there was just enough twilight left to see the view I had been waiting for--the Selkirk Mountains over the Kootenai Valley. 

Kootenai Valley view looking south

Even though I could only make out the major features in the fading light, the view is etched in my mind from descending the hill many times. The tree-covered slopes of Trout Creek and Ball Creek stand above the patchwork of fields in the valley. The north bench a checkerboard of fields, forests and homesites. 

Kootenai Valley view looking north

After being away for seven months in Alaska, I realized how much I take for granted in Boundary County--the wildlife, the trees and the land. After only seeing three animals bigger than a snowshoe hare all summer (lynx, caribou and black bear each once), I’m looking forward to deer and turkeys walking through my yard, watching elk herds and coyotes in the fields, and finding moose browsing up Myrtle Creek. I take for granted the variety and abundance of our big game animals. I enjoy seeing the tracks of the more elusive critters of the mountains--cougars, marten, bobcat and lynx, to name a few--because I know that if I spend enough time outside I will eventually see the animal itself. 

Selkirk Mountains and Kootenai Valley from Tungsten Mountain (looking west)

Even during a short walk in the woods, I hear the nasally twang of a nuthatch, the piercing scream of an eagle overhead or the funny call of the pileated woodpecker. The woods are filled with so many sounds that I often don’t pay attention to, including the wind blowing through the towering pine trees.

Oh, how nice it is to see trees larger than six inches across and 20 feet tall. As we drove from Alaska to Idaho, I could see the progression of increasing tree height and variety. The short black and white spruce of the boreal forest slowly grew taller and then started to include tamarack (which later changed to larch). Then farther down the road came the lodgepole pine, then hemlock and cedar, and then Douglas fir. Only after passing through Radium Hot Springs did the ponderosa pine appear along with one of my favorite things about autumn--hillsides covered in a mosaic of green and gold. Larch make autumn colorful when the forests are dominated by conifers. 

From alpine fir to yew, the land here supports a diverse array of trees. When looking along the edge of a field, the assortment of trees is evident in shape and color, with each conifer having its own shade of green (and yellow in the fall for the larch). 

Looking north over the Kootenai Valley from Clifty Mountain

When overlooking the valley, the combination of forests with logging, open fields with tractors, pastures with grazing livestock and horses, and the meandering Kootenai River make the view complete. I’m glad to be home. 

Note: Published in the Bonners Ferry Herald on October 25, 2012. 

Camouflage a means of survival

I catch a slight movement out of the corner of my eye and stop to scan the brushy slope. After a few seconds I spy a ruffed grouse with its head held high next to a birch tree. If the grouse hadn’t twitched I would have walked right past, like so many other times. 

While animals don’t have printed patterns of needles, leaves and grass on them like hunters do, they have various techniques that camouflage them in their habitat. 

A snowshoe hare molting from white to brown in the spring

Ptarmigan, snowshoe hares and some weasels trade in their brown summer coat/plumage for a snow white coat that allows them to go undetected against the snowy winter landscape unless there is a late winter or early spring. Then these white creatures will stand out against the brown landscape like a beacon in the dark.

Can you find the ptarmigan?

White-tailed deer also change color with the season but not to the extent of snowshoe hares. During winter, white-tailed deer have a grayish-brown coat to help them blend in with the dead grass and drab colors of the leafless forest. Come summer, their coats will turn a tan to reddish-brown color. 

In addition to color, markings help camouflage an animal. White-tailed deer fawns are born tan to reddish-brown like their mothers, but they also have white spots. These spots are highly visible in broad daylight but they mimic the dappled shade of the tall grasses where a fawn waits for its mother. 

While a few birds are brightly colored like the red northern cardinal, many more are outfitted in varying shades of brown and tan. With the addition of spots, streaks and stripes, such as on the turkey or brown creeper, they often go undetected except for  movement or sound. Brightly colored birds will often molt into drab colors for the winter in order to be camouflaged. 

Can you find the three grouse in the boreal forest?

As unlikely as it seems, the bold tan, white and black bands on a killdeer make it virtually impossible to see while it sits on its eggs among stones of similar color. This type of camouflage is considered disruptive coloration because the contrasting colors or markings break up the outline of the animal which makes it harder to see. 

Other creatures rely on pure deception to keep them alive, especially insects. These insects, such as praying mantis, look just like the leaves and stems on the plant they rest upon. Some butterflies and moths look exactly like the tree bark on which they rest, lichens included. 

A grasshopper in late summer blends in with dried grass stems

Camouflage helps an animal look like the vegetation, soil or rocks where it lives, even if that means underwater. How often have you peered into crystal clear water and seen only rocks? Then the slightest flick of a tail reveals a fish camouflaged against the sunlit rocks. Besides coloring and markings, fish stay camouflaged by countershading--a technique where a creature’s back is dark and the underside is light. The dark, speckled backs of fish help them blend in with the plants and rocks of the bottom when viewed above by fish-hungry herons, hawks, eagles and osprey. Their silvery undersides keep their silhouettes against the surface from becoming too obvious to predatory fish lurking below. 

Being camouflage not only helps animals survive by not being eaten, but it also helps predatory animals hunt. Predators need to be as concealed as their prey in order to sneak up on their next meal. No matter how well camouflaged either the prey or predator is, the slightest movement can make the difference between surviving or not. 

Note: Published in the Bonners Ferry Herald on October 18, 2012. 

Mighty Yukon River

From the time I leave Bettles, Alaska until I cross over the Cassiar Mountains east of Whitehorse, Yukon on the Alaska Highway, I will be traveling almost entirely in the Yukon River watershed. Only one area along the Alaska Highway near Haines Junction drains to the Pacific Ocean through the Saint Elias Mountains (the Dezadeash/Alsek River).

At approximately 330,000 square miles, the Yukon River watershed is the fifth largest in North America. Despite the huge area the Yukon River drains, the inhabitants are few, roughly 128,000 people, and that includes the major towns of Fairbanks and Whitehorse. Compare that to Spokane, Washington which has a population of 210,103 people or even Kootenai County (Idaho) with 141,132 people, both of which are located in the Columbia River Basin that encompasses 258,000 square miles. 

Crater Lake on the north side of Chilkoot Pass is part of the Yukon River watershed

From the northern reaches of the Coastal Range mountains in British Columbia to the southern slopes of the Brooks Range in Alaska to the Bering Sea, the Yukon River creates a large arc through the Yukon Territory and Alaska. The water in the Koyukuk River flowing past Bettles eventually ends up in the same place as that flowing from Lake Lindeman on the Chilkoot Trail--the Bering Sea. 

Before the Yukon River reaches the Bering Sea, it spreads out into an extensive delta, 40 to 60 miles wide in some areas (which is approximately the distance from Porthill to Sandpoint). This extensive area of wetlands is some of the most productive goose and shorebird nesting habitat in Alaska--over 100 million shorebirds and waterfowl migrate there to nest. The delta is also the starting location for one of the largest Chinook, Chum and Coho Pacific salmon runs in the world. 

Llewellyn Glacier and Atlin Lake--the headwaters of the Yukon River

From the Bering Sea to its glacial headwaters at the south end of Atlin Lake in British Columbia, the Yukon River traverses 1,980 miles, making it the third longest river in North America (the Mississippi River is first and the Mackenzie River in northern Canada is second) and the twentieth longest in the world. 

Over those nearly 2,000 miles, only 17 communities dot the main river banks, however, more exist on the tributaries. Fewer yet are the number of bridges--only four--along the entire length. The Yukon River bridge on the Dalton Highway (also called the Haul Road) is the only bridge that crosses the Yukon River in Alaska. 

The only bridge that crosses the Yukon River in Alaska

Before bridges and roads were built, sternwheelers navigated the Yukon River from the Bering Sea all the way to Whitehorse. This was the main method of travel in the watershed, especially during the gold rush days. Once the Klondike Highway was completed in the 1950‘s and connected Dawson City to Whitehorse (and the rest of North America’s road system), the need for sternwheelers plummeted. 

With minimal roads, only a small portion of the Yukon River watershed is accessible by road. The nearly thousand-mile drive from north of the Arctic Circle to east of Whitehorse crosses the Yukon River only twice but crosses dozens of small and large tributaries that all flow into the mighty Yukon. 

Note: Published in the Bonners Ferry Herald on Oct. 11, 2012. 

What’s that protruding from your head?

Often I catch myself using the terms antler and horn interchangeably, such as “I’m going horn hunting”, even though I know they are different. One of the obvious differences is that antlers are shed annually while horns are not, which is why I go shed (antler) hunting and not horn hunting.  

Living in north Idaho, we are surrounded by mammals with antlers--moose, white-tailed deer, mule deer and elk. Wild mammals bearing horns are fewer (bighorn sheep and mountain goats) or farther away (buffalo and muskox), which makes horns all the more intriguing. 

Woodland buffalo

Every time I drive through the Thompson Falls area in Montana, I watch for Rocky Mountain bighorn sheep along the roadside. On mature rams, the massive, curled horns can weigh up to 30 pounds--which is small compared to the 80-pound pair of antlers a mature moose can grow in one year. On rams, the age can be determined by counting the number of growth rings. Those growth rings are composed of keratin, a fibrous protein, which comprises the outer covering of the horn. The inside of the horn is composed of a living bony core. 

Not only is keratin an integral part of horns but also a component in the claws and hooves of mammals; hair, nails and skin of people; scales and claws of reptiles; shells of turtles and tortoises; feathers, beaks and claws of birds; the quills of porcupines and the baleen of whales. A rhinoceros’s ‘horn’ is entirely composed of keratin and therefore isn’t considered a true horn because it lacks a bony core. 

Similarly, giraffe ‘horns’ are not true horns because even though they have a bony core the horns are covered with furred skin, not a keratinized sheath. Another mammal that is considered to have horns is the pronghorn antelope. 

The pronghorn antelope’s horns are a cross between horns and antlers. They have a bony core and a keratinized sheath but the sheath is shed annually like antlers. Also, a pronghorn’s horn is branched (hence the name pronghorn) and true horns are unbranched. Pronghorn antelope are the only animal in the world to have a forked ‘horn’ that is partially shed every year. 

Pronghorn antelope shed the horn's keratinized sheath every year

Even though true horns are unbranched, they can take on unique shapes--the full curl of the bighorn sheep or the spiraled horns of the spiral-horned antelope. The curves and spiral shapes are caused by growth pulses that result in some areas growing faster and thinner while other areas grow slower and thicker. 

Since horns grow continuously throughout an animal’s life, one might think there would be little nubbins of horns at birth. However, horns begin as small bony growths under the skin in the subcutaneous connective tissue and are not even attached to the skull. These small growths (called ossicones) will fuse to the skull bones sometime after birth and up to four years later in giraffes. 

Bighorn sheep horns will eventually grow into a full curl

Even though giraffes, rhinoceros and pronghorns don’t have true horns, it is easier to say they have horns than to figure out what to call the structures protruding from their head. One thing for sure is that they are not antlers. 

Note: Published in the Bonners Ferry Herald on October 4, 2012.