South Yuba River State Park

Upper arm of Englebright Lake

Last week we drove down to the South Yuba River State Park and went hiking.  This foothill park is located in an oak woodland, about 2,000' lower in elevation than my neighborhood.  It is one of my favorite places to go in the winter and the spring.  In the spring it is a riot of wildflowers!  In the winter it is snow-free, populated with birds, and quite a bit warmer than my neighborhood!  This time we hiked along the upper arm of Englebright Lake, where the combined North and Middle Forks of the Yuba River merge with the lake.  It was a little wintery but not cold, and still had some beautiful fall color!

Englebright Lake

Most striking were the willows that have lasted and lasted this year, and still glowed a deep, rich yellow along the lakeshore.

Bald Eagle - Haliaeetus leucocephalus

As soon as we got out of the car I spotted a big raptor in a distant tree!  I walked towards it and managed to get a few photos before it flew off.  

It was a Bald Eagle!!!  What an amazing start to the day!

Toyon - Pacific Madrone

Heteromeles arbutifolia - Arbutus menziesii

I live in a mixed conifer forest.  Down in the foothills, the vegetation is totally different!  We hiked through a mainly Blue Oak forest along the lake, that was interspersed with Black Oak, Canyon Live Oak, Interior Live Oak, Madrone, Toyon, Buckeye, and Gray Pine.  The Madrone and Toyon had tons of berries!

Toyon berries form in June or July, but don't ripen until December! When they are green they contain cyano-glucosides in their pulp. When a bird tries to eat a green berry, cyanide gas is released and deters the bird! The un-ripened berries are also full of bitter tannins that discourage foragers! Over time the cyanide compounds gradually move into the seeds and the tannins diminish. In December, when the berries are bright red, they aren't bitter and the pulp no longer contains cyanide compounds! Approximately 20+ species of birds eat Toyon berries during winter! In addition to Western Bluebirds, you might see Band-tailed Pigeons, Cedar Waxwings, Hermit Thrushes, and Varied Thrushes feeding on them! Foxes, Brush Rabbits, Black Bears, and Coyotes also feed on the ripened berries!

As for Madrone berries, Wikipedia states, "Native Americans ate the berries raw and cooked, but because the berries have a high tannin content and are thus astringent, they more often chewed them or made them into a cider. Overeating causes cramps. The Native Americans also used the berries to make necklaces and other decorations, and as bait for fishing. Bark and leaves were used to treat stomach aches, cramps, skin ailments, and sore throats. The bark was often made into a tea to be drunk for these medicinal purposes. Many mammal and bird species feed off the berries, including American Robins, Cedar Waxwings, Band-tailed Pigeons, Varied Thrushes, Quail, Mule Deer, Raccoons, Ring-tailed Cats, and Black Bears. Mule deer will also eat the young shoots when the trees are regenerating after fire." 

Ruby-crowned Kinglet - Regulus calendula

In the bushes along the trail we kept hearing a rattling call, but were unable to identify what bird was singing.  There were lots of little birds flitting around in the bushes. They were hard to identify or photograph because they kept moving around, resting a second or less in one spot.  Later on we got a clear view of a Ruby-crowned Kinglet making the rattling calll!  Ruby-crowned Kinglets are named for the bright scarlet "crown patch" the male exhibits when excited or antagonized.  Most of the time the crown isn't visible. These tiny birds mainly inhabit the snow-free foothills during winter, but move up to the Lodgepole/Hemlock forests to breed, around 9000' in elevation. I've seen these little birds all winter in my neighborhood this year. Their fluffy, thick plumage keeps them warm at night.  For food, they glean small insects off of twigs and branches.

What was most interesting about the day, was the number of bird feathers we saw on the ground.  They were scattered along the trail wherever we went!  Apparently birds were getting eaten on a regular basis!  Birds are eaten by mammals, such as foxes and weasels, as well as by other birds, mostly raptors.  

Some raptors will pluck the feathers off their prey before they eat them.  

Which is probably why all these feathers were in one spot.

Most raptors eat their entire prey, but feathers, fur, and bones aren't easily digested so they regurgitate them.  We found this big pile of feathers and bones on the trail!  We have no idea what kind of bird may have done this, but probably a raptor of some kind.  The following information on raptor regurgitation is from http://fauconeduc.biz/documents/pelletguide09_10.pd.

"Most raptors eat their entire prey. Some owls even eat them whole, in one gulp, when they are small enough of course! The bird’s stomach can digest the meat, the fat and other tissues but not the feathers, fur or bones of the prey. All these non-digested parts create a pellet in the bird’s gizzard, an organ of the digestive system. The process of digestion and of forming a pellet can take between 6 and 24 hours depending on the type and the size of the prey eaten. It is important the bird coughs up this mass of nondigested parts because it could get in the way of the absorption of nutrients and cause certain health problems. The pellet gets coated with protective mucus when it leaves the gizzard to be regurgitated; this prevents the throat irritation and makes it easier to regurgitate.

When dissecting a pellet you might find a wide variety of things inside: skulls, beaks, various bones, insect exoskeletons, etc. The content will allow you to identify the type and number of prey the bird ate. For example, if you find three skulls, this means that the bird ate three animals during the last day. Moreover, if the skulls are incomplete, they are likely to be from birds since their bones are fragile whereas if the skulls are intact, they are probably from rodents. Finally, it is usually easy to tell apart the two prey skulls since you can see small teeth on mammal skulls and none on the birds’.

Nocturnal raptors (owls) have a generally less efficient digestive system than that of diurnal raptors and as a result, produce impressive pellets. Owls’ pellets can contain up to 10 times more bones than those of diurnal raptors (eagles, vultures, hawks and falcons). They can measure between 2.5 and 10 cm and are good indicators of the prey consumed. Also, the size, color and content of a pellet can indicate what raptor produced it. If for example, a pellet contains a lot of insects, there is a good chance it was produced by an Eastern Screech Owl since they eat bugs, or if the pellet is very large, it would be from a Great Horned Owl which has

a larger stomach."

It was a peaceful, gray, overcast day, subdued in sound and light, and by the 

late afternoon it started to rain!  How wonderful!

Dogwood in the Rain

Weather Update!

It started raining the afternoon we were down at Englebright Lake, and by the end of the week, we had a total rainfall of 3.30"!  Yahoo!  The snow level was around 4,500' so I'm sure the Lakes Basin has several inches of new snow on the ground!  I hope this wet winter weather lasts and lasts!  The storms pretty much knocked off the last of the fall leaves, but I still found a few hanging on!  

Rose leaves in the Rain

We still need stormy, wet Weather!

Even though we got 5.13" of rain in November, and another 3.30" this past week, we still need a LOT more. I am once again sending out a "Call for Art", this time in celebration of winter weather. My intention is to focus on the need for rain or snow, and through collective positive energy invoke them 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 check out my blog at dampearthart.blogspot.com. I will be posting new art weekly.

You can view what was submitted last year at dampearth.blogspot.com.

Check it out and pray for rain!

American Dipper with smoke-colored Sparkles - Cinclus mexicanus

River Birds!

Back in my neighborhood, there is one Great Blue Heron, two Belted Kingfishers, a few Black Phoebes, one Bald Eagle, and several American Dippers that have been commonly seen along the river this winter!  Most of these birds live here year-round, except for the Bald Eagle who is a part-time resident.  I thought I'd focus on the American Dippers for this blog, as they are such amazing river dwellers!

American Dippers are the only aquatic songbird in North America!  Lately I've been hearing them sing some amazingly varied songs!  It turns out that fall, early winter, and early spring are when they sing the most.  They are quiet in spring and summer when raising their offspring.  They were John Muir's favorite bird.  The following passage from his book, The Mountains of California, has a lovely description of the American Dipper's song. 

"But as soon as the winter clouds have bloomed, and the mountain treasuries are once more replenished with snow, the voices of the streams and ouzels increase in strength and richness until the flood season of early summer. Then the torrents chant their noblest anthems, and then is the flood-time of our songster's melody. As for weather, dark days and sun days are the same to him. The voices of most song-birds, however joyous, suffer a long winter eclipse; but the Ouzel sings on through all the seasons and every kind of storm. Indeed no storm can be more violent than those of the waterfalls in the midst of which he delights to dwell. However dark and boisterous the weather, snowing, blowing, or cloudy, all the same he sings, and with never a note of sadness. No need of spring sunshine to thaw his song, for it never freezes. Never shall you hear anything wintry from his warm breast; no pinched cheeping, no wavering notes between sorrow and joy; his mellow, fluty voice is ever tuned to downright gladness, as free from dejection as cock-crowing."

(You can read John Muir's whole chapter on American Dippers at: https://vault.sierraclub.org/john_muir_exhibit/writings/the_mountains_of_california/chapter_13.aspx)

American Dipper at nest with Nestlings - Cinclus mexicanus

Pair formation begins in winter.  Both the male and female sing quite loudly in order to be heard by their mate or potential mate, over the sound of the rushing water!  Although Dippers do not mate for life, they often mate with the same female several years in a row!  Some males will mate with more than one female.  A mated pair will defend their long linear "territory" on a river or stream, and keep intruders/competitors away from their nesting area.  Both male and female build the nest, and care for the fledglings. Pairs will live together year-round if food and habitat are available. 

 American Dipper Underwater - Cinclus mexicanus

For food, they dive underwater and eat aquatic insects and larvae as well as tiny fish.  They have powerful legs, long toes (NOT webbed) and streamlined bodies that makes walking on underwater rocks, in swift currents, possible.  They also swim underwater using their wings like flippers and their tail like a rudder.  With a heavy coat of oil on their outer feathers coupled with a dense coat of downy feathers underneath, Dippers can tolerate the frigid winter river.  They have twice as many feathers as any songbird their size, even their eyelids are feathered!  As they dive under the water, special scales slide to cover their nostrils and nictitating membranes cover their eyes!  The membranes are hinged at the inner side of the eyes and sweep horizontally across the corneas.  The scales keep water out of the Dipper's nose, and the membranes make it possible for it to see underwater.

American Dipper in Snow - Cinclus mexicanus

Their feet don't freeze in the frigid water, for a variety of reasons. 

In heat exchange, the closer two temperatures are (eg. creek water and bird feet) the less heat is exchanged. So if you have cold feet, you don't lose much heat to ice or snow. Their feet are cold because of the counter-current heat exchange system between the arteries and veins in their feet. Warm arterial blood flowing to the feet passes close to the cold venous blood returning from the feet. The arterial blood warms up the venous blood, thus lowering the arterial blood's temperature. This makes the arterial blood relatively cool when it flows through the feet, and less heat exchange occurs. The cooled blood provides just enough oxygen and food to tissues, and just enough warmth to avoid frostbite! Surprisingly most birds only lose about 5% of their body heat through their feet!

Does lichen have the same relationship with rain/water that moss has?

What are the deer doing?

What's happening in the Lakes Basin?

Check back next week for the answers to these questions and more!

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