Mourning Dove - Zenaida macroura
We had a snowy week this week, with a total precipitation of 5.01"! It snowed and rained Tuesday through Friday. Right now we have about 6" of snow on the ground! The forecast had predicted heavy winds, but luckily that didn't happen. The Lakes Basin and Yuba Pass probably have 4-6 feet (or more) of snow on the ground! Yahoo! What a gift this storm was, now we have a substantial snowpack! The forecast is for snow and rain showers over the next 5 days. I hope the storms keep coming and coming!
For weather updates I use https://www.cnrfc.noaa.gov/. All you need to do is type in your location, and tons of information becomes available, including 1 to 168 hour precipitation totals, current snow depths, temperatures, and forecasts. Check it out, it may be just what you need!
Varied Thrush (male-female) - Ixoreus naevius
Snowy wet weather is one of the hardest conditions for wild birds. Their feathers can protect them from rain and keep them warm, but not for days and days. Additionally with snow covering the ground, food such as seeds and dormant insects isn't easily available. So I provide extra bird seed for wild birds during heavy winter storms. This week lots of birds were at our feeding station, including the usual Dark-eyed Juncos, Spotted Towhees, Fox Sparrows, Mountain Quail, and a few Mourning Doves. We also had a pair of Varied Thrushes showed up this week, as well as a flock of about 25 Pine Siskins! It is such a pleasure to watch these beautiful birds!
Varied Thrushes don't live here, but usually one pair visits for a few days in the winter. They breed north of here, in Washington, Oregon, British Columbia, and Alaska, as well as in western Montana and Idaho. In winter they eat acorns, seeds, nuts and berries. The male is more boldly marked than the female, with its chest band a dark navy blue.
Pine Siskins - Spinus pinus
Pine Siskins are nomadic finches that range widely and erratically in response to seed crops. Their main food in winter is cone seeds and tree buds. Locally they've been eating the seeds from last year's alder cones. When food is plentiful they will store lots of seeds in their crop, which gets them through cold winter nights. Unlike hummingbirds, that go into a state of torpor overnight, Pine Siskins ramp up their metabolic rate to stay warm at night! They also put on a layer of fat for winter! I love watching these little birds and hearing their busy chatter as they forage on the ground, and perch in the trees!
The Subnivean
Zone
With about 6-8 inches of snow on the ground right now, I thought it would be appropriate to discuss what goes on under the
snow! The following information from
https://yosemite.org/getting-in-the-subnivean-zone/ explains it clearly!
"The
below-snow haven is the subnivean zone, a very real facet of winter life
for many mammals. “Subnivean” zone – from the Latin
for under and snow – refers to the small space (about
1") between the ground and the bottom of the snowpack. As snow piles up, heat
from the ground warms the lowest layer of flakes, transforming them into water
vapor. The vapor freezes, creating a cozy winter home: icy roof above, bare
ground below. Subnivean spaces can also form when tree branches, leaf piles and
other natural objects hold snow off the ground.
We often talk about snow
“blanketing” the earth – for some of the local smallest animals, including
mice, voles and shrews, that’s not just a nice turn of phrase. As animals
around them head south, nestle into dens or don their cold-weather coats,
another group of creatures moves into a wild, bustling winter world that
remains, for the most part, out of our view. For them, the layer of snow above
their subnivean hollows serves as an insulating, and essential quilt, blocking out
the wind and keeping below-snow temperatures at around a relatively balmy 32
degrees Fahrenheit.
Throughout the winter,
subnivean-dwelling mammals move through a network of snow-covered tunnels,
snacking on leaves, seeds and bark, or feasting on insect eggs and larvae. Some
animals stockpile sustenance in preparation for winter, while others take a
more spontaneous approach, eating what they can find. Holes connecting the
tunnels to the surface provide vital ventilation, allowing carbon dioxide to escape.
To the human senses, the
subnivean zone is nearly invisible. We might spot tiny tracks leading to small
entrance holes or see the remnants of icy-roofed tunnels as the snow starts to
melt, but usually the bustling sub-snow ecosystem eludes our notice.
For the animals that depend on
subnivean life for survival, however, that winter world is a constant focal
point. Coyotes listen for subtle movements in blanketed meadows; when they
sense potential prey scurrying underfoot, they plunge headfirst into the snow
to nab their meal. Owls. too, use their extraordinary hearing to listen for
tiny feet pattering through subnivean tunnels, then swoop down to scoop up
their quarry. Short-tailed weasels, which sport a brown coat in warm months but
wear white in winter, take advantage of their small size and snow-colored
camouflage to slide into subnivean tunnels and hunt below the snow."
In the Spring you can see the evidence of
Pocket Gopher activity in the subnivean zone.
They bring dirt to the surface from their underground tunnels. Due to the covering of snow, they can't pile
up dirt on the forest floor. Instead,
they make tunnels in the subnivean layer and fill them with dirt. When the snow melts in the Spring you often
see these tube-shaped lines of dirt on the forest floor!
Chickaree/Douglas Squirrel - Mouse - Quail
On top of the Snow!
Now that the snow has settled and the weather has improved, tracks have started to appear everywhere in my neighborhood! Once again I am amazed at the flurry of activity these tracks tell! Edwin Way Teale describes it perfectly in the following quote, from his book Wandering through Winter ©1965.
"On this day, wherever we went, no animal had stirred without writing the story of its activity on the surface of the drifts. Snow is the great revealer. It cannot keep a secret. All through the woods around us it was filled with the gossip of the night. For most of the creatures whose tracks we saw are nocturnal."
In most of the tracking field guides, tracks look defined and perfect. In reality, tracks in the snow vary greatly in appearance. Tracking is actually quite complicated! Here's a list of some of the things you need to notice when trying to figure out a track:
How many toes are there?
Are any claws present?
How wide and how long are the footprints?
What is the length of one full step?
How deep is the track?
How old is the track?
Is there any scat that might identify who left the track?
Where is the track located?
As you can see, there's LOTS to learn about tracking. I use the field guide Mammal Finder by Ron Russo and Pam Olhausen to identify tracks. It is an excellent resource!
Gray Fox (maybe) - Western Gray Squirrel
Deer - Raccoon - Gray Fox
Porcupine - Erethizon dorsatum
The porcupine tracks were a mystery to me! I took this photo several years ago, but could never figure out what animal it was! In 2017, I emailed the photo and a query to a website, www.northernnaturalists.com, that specialized in tracking animals. They identified it as a porcupine, mainly because of the size of its pigeon-toed track! Wow! I have only seen one porcupine in my life. It was up in a pine tree in the winter, in the Lakes Basin, about 25 years ago. It was so camouflaged by the pine needles that I didn't notice it, but my dog did! Its quills looked just like the long needles of the tree! Unfortunately I didn't get a photo, but it was great to see one! Porcupines remain active year-round. In winter they eat the cambium layer of trees, usually Lodegpole Pines, fir, cedar, and hemlock! They are solitary creatures, except during mating season in the fall. Their winter home is usually in rock crevice shelter, or a cave among rocks. They are primarily nocturnal, but may be seen resting in the top of a tree during the day!
"One problem is that many wild forests have been clear-cut and converted to tree plantations with row upon row of Ponderosa pines, which happen to be one of the porcupine’s favorites. As a result, the logging industry for decades waged an extermination campaign against the porcupine, using hired hunters as well as rodenticides. John Heil, a spokesman for the U.S. Forest Service regional headquarters in Vallejo, said the agency stopped targeting porcupines in 1977."
North Yuba River - 1/29/21
More Damp Earth Art!
Since the local rainfall total at this point is way below our normal amount, I am once again sending out a "Call for Art" in celebration of rain. My intention is to focus on the need for rain, and through collective positive energy invoke rain to fall. It is just a wish, a thought, and a hope. If you would like to submit some art, or writing, or a photo please email me at northyubanaturalist@gmail.com. Check out what's already been submitted at dampearthart.blogspot.com
I will be posting new art weekly. Check it out and pray for rain!
How's the "Open Slope" Kestrel doing?
What's happening at the local ponds?
Check back next week for the answers to these questions and more!
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Something changed at Blogspot.com. Oh well... However, my blog looks better if you just go to northyubanaturalist.blogspot.com, rather than get the emailed version. I suggest that you just bookmark my blog and visit it every Sunday afternoon!
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