Down in the Foothills

Western Bluebird - Sialia mexicana  & Toyon - Heteromeles arbutifolia

Toyon Berries!

Every year on Christmas Day we go for a hike! This year we went down to the foothills near Bullard's Bar Reservoir, and hiked on the Yuba Rim Trail. There's a dry meadow rimmed with shrubs and pines right at the beginning of the trail, and that's where we saw a lot of birds! About a dozen Western Bluebirds were busy feeding on the Toyon berries! It was so beautiful to watch!

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!

     Swainson's Thrush - Catharus ustulatus     &     Hermit Thrush - Catharus guttatus

Thrushes!

We lucked out and saw two Hermit Thrushes in the bushes on the edge of the same meadow!  I had never seen them before!!!  Their name comes from their solitary elusive behavior!  They are really similar in appearance to Swainson's Thrushes (above left), but behaviorally they differ.  When perching, Swainson's Thrushes are relatively still, while Hermit Thrushes flit their wings about and pump their tails!  In the summer both species eat a lot of insects, but feed on fruit and berries, including Toyon, in winter!  The Swainson's Thrush migrates south to Mexico and Central America for winter, whereas the Hermit Thrush remains in California!  I stopped by the same meadow yesterday, but didn't see a single bird!  The Toyon berries were all gone!  We were so lucky to have seen these birds a week ago! 

For more information on the Yuba Rim Trail check out their website at http://www.bylt.org/trail/yuba-rim-trail/.

Mistletoe - Phoradendron sp. & Western Bluebirds - Sialia mexicana

Mistletoe!

Another favorite food for many critters during the winter are Mistletoe berries!   Over 28 species of birds in California eat the berries, as well as gray squirrels, raccoons, pine martens, chipmunks, porcupines, and ringtails!  Sheesh!  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! 

I looked and looked at a lot of mistletoe plants in the foothills, but only found a few of them that still had berries on them!  I didn't see any animals or birds feeding on them either.  There's another area, closer to my neighborhood, that I know has a lot of mistletoe.  I'll have to go check it out!  

Turkey Vulture - Cathartes aura - decayed beak (inset)

Turkey Vultures

While we were down in the foothills, I found a dead Turkey Vulture on the side of the road!  It was HUGE!  They have a body length of approximately 27", and a wingspan of up to 69"!!!  The body had mostly decayed and dried up, but the feathers and wings were still intact!  The feathers were incredibly beautiful!  Up close they looked like cresting waves!  I must have taken 25 pictures of just the feathers!  Such beauty!!!  Overhead there were lots of Turkey Vultures soaring around looking for something to eat.  They almost exclusively eat carrion, so road kills are one of their main food sources.  You can easily identify Turkey Vultures by their size, the splayed out feathers at the tips of their wings, and how they soar and soar without flapping their wings!  Turkey Vultures also have naked red heads!  In winter you can find Turkey Vultures in the foothills, California's Central Valley, and as far south as northern South America!  They usually hunt and feed on their own, but readily feed communally without any fighting!  In the evenings they will often congregate in large groups to roost!  

Turkey Vulture feathers!

Steller's Jays - Cyanocitta stelleri    &   Song Sparrow (inset) - Melospiza melodia

FeederWatch Update!

I've been watching our feeder now for about 6 weeks.  During the last 3 weeks, it has pretty much settled down to a regular group of customers!  The first to arrive are the Steller's Jays, usually 16 of them!  They are quickly followed by approximately 22 Juncos, 2 Song Sparrows, 2 Spotted Towhees, and 1 Golden-Crowned Sparrow!  They feed continuously until all the seed is gone, approximately 30 minutes!  I only feed them once a day, in the morning!  

It's really interesting to watch the group dynamics!  All 16 Steller's Jay are never feeding at the same time!  Usually 9 or 10 will be feeding, and then another one lands and two or three take off!  The small birds seem to eat all at once, but fly off at the slightest movement!  

It's been fun counting and observing them!  I'm happy to help the "Citizen Science" movement!  By turning in my observations, data is made available to scientists that they couldn't get on their own.  There are many websites that are set up for the input of citizen scientists!  Just Google "Citizen Science" to get started!  You'll be amazed at all the opportunities available!

Dark-eyed Juncos  (female, left - male, right) - Junco hyemalis

Cooper's Hawk juvenile (?) - Accipiter cooperii (?)
Photo by B.J. Jordan ©2017

Cooper's Hawk juvenile? 

My friend and local resident, B.J. Jordan, watched this beautiful juvenile hawk recover and fly away, after it crashed into a window in her house!!!   It took quite a while for it to recover, and she was able to take these lovely photos before it took off!

I asked a friend of mine, Walt Carnahan, who is a former president of the Audubon Society - Grass Valley Chapter, to identify this hawk.  Here's what he said.

"This one's tough. The size of the bird would be useful.  My first guess was a Cooper's. But the dark streaking is a little off color.  CA. Merlin might work.  But I don't see any sideburns.  Forced to choose I'd go with a Cooper's.  Other candidates would be a Goshawk (wrong striping on breast) or a Sharp-shinned.  Do you have a whole bird picture that is not on the ground?"

The bird was about 16" tall, but B.J. didn't get a picture of it off the ground.

If it is a Cooper's Hawk, it's an incredible hunter.  They are relentless pursuers of their prey, which is usually medium size birds such as quail, as well as rabbits, squirrels, mice, and reptiles.  With their short wings and rudder-like long tails they can "turn-on-a-dime" and maneuver easily through forests and dense thickets!  It's a rare event that a Cooper's Hawk doesn't catch its prey, unless a tree intervenes!  Almost one fourth of the Cooper's Hawks that have been examined, have breastbones that have healed fractures!  Unlike falcons who kill by biting their prey, Cooper's Hawks squeeze their prey to death with their feet!  Wow!!!

Cooper's Hawk juvenile (?) - Accipiter cooperii (?)

Photos by B.J. Jordan ©2017

Coccora (?) - Amanita calyptroderma (?)     &     mushroom - species unknown
  

Mushrooms!

There are still a few mushrooms to be found in the dark, damp, cool places in my neighborhood!  The weather forecast is for rain this week, so perhaps they will start popping up again!  My neighbor told me about the purple ones (above right)!  They really were PURPLE, but I have no idea what kind they are!  Wow!  I'm keeping my  fingers crossed and hoping for RAIN!

These tiny insects are springtails!  

Actually, they're not insects, they're arthropods!  More on that later!

There are 5 different animal tracks in this photo: deer, goose, quail, fox, and mice (woodrat?).

What are the foxes up to?

Where are the deer?

What's happening in the river?

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

Your comments & questions are greatly appreciated!

Please email me at northyubanaturalist@gmail.com, 

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click on the comments just below, to post a comment!  

Thanks!