Cold & Gray

North Yuba River - Winter

This week it was mostly cold, gray, and misty. The temperature hovered in the 40's. The river was low and COLD! I measured it, and it was a chilly 43°!  I haven't seen any fish, Mergansers, Kingfishers, or Great Blue Herons lately!  It feels really quiet and still.  I wandered for hours watching the mists rise on the ridges and canyons.  The damp cold chilled me completely, but I relished the moist air! 

 On Friday, .2" of rain fell, and more was predicted for Sunday.  So far our total rainfall for this "water year" (10/01/18 through 9/30/19) is 9.41".  Our average rainfall is around 60".  Hopefully the next couple of days will bring our total up a bit. 

old Alder cones up close - this year's Alder cones

After the rain fell a few weeks ago, the river was an opaque mocha color. Within a few days it changed to a clear brown, and now it's back to its beautiful glass-green color. The opaque milky-brown color occurs when sediments are first washed into the river. As the sediments settle, the river changes to a clear-brown color which is caused by all the tannins leached from plants.  Last week I posted this photo (above, left) of old alder cones.  I think the water drops on the cones are amber in color because they contain tannins!  I'm not 100% positive, but it seems the most plausible explanation.

The following excerpt from an online article explains tannins well.
"Tannins occur in many species of coniferous trees as well as a number of flowering plant families. These tannins can leach out of the plants. The water in the soil becomes rich with tannins and seeps into the ground water or drains into lakes and streams. These waters become brown in color and look like tea. Tannins are found commonly in the bark of trees, wood, leaves, buds, stems, fruits, seeds, roots, and plant galls. In all of these plant structures, tannins help to protect the individual plant species. Tannins that become stored in the bark of trees protect the tree from being infected by bacteria or fungi. Many bud scales on woody plants contain tannins to protect the inner leaf tissue from being consumed and in many seed plants the initial set of leaves from a germinating seed are also high in tannins."

  You can read the entire article at https://www.fs.fed.us/wildflowers/ethnobotany/tannins.shtml

Western Bluebird (female) - White-breasted Nuthatch

Sialia mexicana - Sitta carolinensis

South Yuba River State Park

Last Thursday, we went for a hike down in the Bridgeport area of the South Yuba River State Park.  It is a beautiful oak woodlands with the South Yuba River on one side and the combined forks of the North and Middle Yuba Rivers on the other.  Because it is at a much lower elevation (567') than where I live (2,674'), some of the birds are different!  

We saw several Western Bluebirds while we were there.  In the summer Western Bluebirds are primarily insectivores.  In winter they eat fruits and berries, such as juniper, poison oak, wild grapes, and elderberry.  They also particularly love to eat mistletoe berries, and will sometimes sleep overnight in a clump of mistletoe to defend their find!  They like to live on the edge of open areas, such as meadows or burned areas.  They are short-distance migrants, and generally move down slope in winter.  Males have brilliant plumage, and females are dully colored in comparison.    They are SO beautiful with their brilliant powder-blue feathers!

We also saw one White-breasted Nuthatch!  These are tiny birds, measuring only 5.75" in length!  In general they can be seen foraging head downward on tree trunks and large limbs, but they will also forage in any direction and on the ground.  They chip away bark looking for food, as well as probe in crevices.  They "pair bond" all year long, and will stay together unless one of them dies!  A lot of their time is spent hoarding food throughout their home territory, with only one item per cache!  They do not migrate, and remain in their home territory year-round!  Their name comes from their habit of cramming a nut into a tree trunk crevice, and then hacking it open with their beak!  We all thought it was a little woodpecker when we first saw it, because it seemed to be pecking away at a tree trunk!

Toyon Berries - Mistletoe Berries - Osage Orange fruit

Heteomeles arbutifolia - Phoradendron sp. - Maclura pomifera

As we drove down to the park, we drove past 100's of Toyon bushes loaded with 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 unripened 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!

We also saw lots of mistletoe with berries in the oak trees.  Over 28 species of birds in California eat the berries, as well as gray squirrels, raccoons, pine martens, chipmunks, porcupines, and ringtails!  Mistletoe plants are dioecious, with the male and female species being separate plants. The female plants are the ones that produce berries! Apparently mistletoe berries are so popular that some mammals and birds, including Bluebirds, actually spend the night in them! They may do this to establish "ownership" of the berries, or for the warmth of the dense clumps, no one knows for sure! If you squish a mistletoe berry between your fingers, it will stick to your finger and you can't shake it off!  They have a thick, viscous substance that makes them sticky.  Being sticky, the seeds are easily transported to new areas by birds. 

On the ground near the parking lot, we found several grapefruit-sized fruits of the Osage Orange trees. They are such strange fruits!  We opened one up and it looked like a pineapple inside!  The plant contains latex, which causes the fruits to be bitter and unpalatable to humans and wildlife.  This latex can also cause dermatitis in humans. The plants are dioecious, with the female producing the large fruits.  Osage Orange trees are not native to California.  They are indigenous to the Red River drainage of Oklahoma, Texas, and Arkansas, as well as the Blackland Praries and post oak savannahs.  They were planted across the US by settlers, mainly for hedgerows. .  The name is derived from The Osage Nation, a Midwestern Native American tribe of the Great Plains, who prized the plant for its wood, to make their bows.  The wood is heavy, hard, strong, and flexible, capable of receiving a fine polish.  Today, the heavy, close-grained yellow-orange wood is dense and prized for tool handles, fence posts, and other applications requiring a strong wood that withstands rot.

California Scrub Jay - American Robin

Aphelocoma californica - Turdus migratorius

California Scrub Jays live in the foothills year-round.  They are highly dependent on oaks and acorns.  Acorns are their main food during fall and winter.  One Jay will bury up to 5,000 acorns in small holes in the ground during the months of fall! These acorns will all eventually be dug up and consumed in the following seasons! Like other members of the Corvid family, Scrub Jays are quite intelligent and have excellent memories. They will also eat insects, other nuts and seeds, and ticks off of deer.

All the American Robins have left my neighborhood, but they are abundant down in the foothills right now.  They are short distance migrants, and usually just move up and down in elevation with the seasons.  When looking for food such as insects and worms, they forage on the ground. They catch worms by watching and listening for them!  Wow!  In the fall and winter Robins often roost in large flocks, and spend more time in trees and bushes eating berries and fruit.  

Gray Fox - Chickaree/Douglas Squirrel

Urocyon cinereoargenteus - Tamiasciurus douglasii

Mammal Update

I saw the Gray Fox again!  It watched me one evening, from a distance of about 100 yards, for a minute or so!  As soon as I started heading its way, it quickly left!  I hadn't noticed when I was looking at it, but in the photo its legs look kind of short!  Maybe this is a young fox that's still growing!  Hope I continue seeing it this winter!

The Chickaree that lives in our woodpile, has been busy harvesting and eating dry sunflower seed heads!  We plant sunflowers every year in our garden for the birds to eat.  This is the first year I've noticed a Chickaree eating them!  

Immature Cooper's Hawk (?) - Sharp-shinned Hawk

Accipiter cooperii - Accipiter striatus

Raptor Identification

Figuring out raptors, especially immature ones, is often quite difficult! I use www.inaturalist.org for help with identifying them. Last week, my neighbor Cy found the small dead Hawk in the above photo. It was so small, only 11' in length including its tail, that I thought that maybe it was a Merlin. I posted the photo on inaturalist.org and within hours it had been identified as a Sharp-shinned Hawk, not a Merlin! 

One of the commentators also provided some very helpful info on identifying Merlins. "Merlins have narrow white bands on a dark tail, and white spots on dark backgrounds on the primaries and secondaries. Being falcons, they also have little tubercles in the nostrils, which would be clearly visible in the portrait shot." Wow!

I really hope this little Sharp-shinned Hawk isn't the one I've been watching down by our garden.  The other dead bird I found several years ago on the ground.  It might be an immature Cooper's Hawk, but I'm still waiting on the ID from inaturalist. I'll keep you posted on the result! In the meantime check out www.inaturalist.org, it is an incredible resource!

Sharp-shinned Hawk - Accipiter striatus

Where are all the fungi?

Are the moss and lichen thriving with all this moisture?

What is that Black Phoebe eating this time of year?

What's happening up in the Lakes Basin?

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

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