Common Raven - Corvus corax
Most of the songbirds and waterfowl have left for the winter. Our neighborhood is seemingly quiet and still, due to their absence. However, the year-round residents are now capturing my attention, mainly the corvids!
As a group, corvids are uncommonly smart. A bird's brain, in general, has a small, poorly developed cerebral cortex. Intelligence in mammal brains is associated with the cerebral cortex. However, birds have developed a part of their forebrain, the hyperstriatum (which mammals lack), as their chief organ of intelligence! Smarter birds have a larger hyperstriatum. Additionally, the part of the brain that deals with memory is the hippocampus. Birds that have a large spatial memory have a large hippocampus. A corvid's brain has a large hyperstriatum and a large hippocampus! That's probably why they are so smart!
Common Raven - Corvus corax
Ravens are thought to possibly be the smartest of all Corvids! The smarter the bird, the more latitude it has to modify its inherited patterns. Ravens are capable of learning innovative solutions to newly encountered problems! They have been known to place nuts (e.g. walnuts) on a road and then retrieve them, after cars have driven over them and cracked the shells!
We have two Ravens that live in our canyon, but not right in the immediate area. They live here year-round. I watch them fly by daily as they head down to the highway, from their distant up-canyon roosting area. Occasionally they will perch in a nearby tree. The highway is a good source of food for these ravens, as roadkill provides carrion. Ravens mate for life, and family members usually stick together for years. I haven't ever seen these Ravens with any young. I wonder why!
Steller's Jay - Cyanocitta stelleri
Steller's Jays are also in the Corvid family. There are about 16 of them that live here year-round. Every morning they really squawk to each other. Sometimes they sound quite alarmed! They are very inquisitive, and are usually the first to notice anything new in the area. They eat seeds, insects, fruit, garbage, carrion, and small mammals! Lately I've been watching them fly by with Live Oak acorns in their beaks! Yesterday, I heard what I thought was a woodpecker hammering on a tree trunk. It turned out to be a Steller's Jay pecking on an acorn, that he was holding against the top of a branch! I didn't know that they ate acorns!
Yellow-billed Magpie - Pica nuttalli
The Yellow-billed Magpie that has been living in our neighborhood for 3 months is also a corvid! Its residence here is an anomaly for a magpie. Usually these birds inhabit the Central Valley, and valleys of the Coast Range, year-round in California. Oak savannah is their preferred habitat, with open pastures or cultivated fields, and orchards. They also usually roost communally with up to 800 other birds! So far it is the only one in our area!
The Yellow-billed Magpie that has been living in our neighborhood for 3 months is also a corvid! Its residence here is an anomaly for a magpie. Usually these birds inhabit the Central Valley, and valleys of the Coast Range, year-round in California. Oak savannah is their preferred habitat, with open pastures or cultivated fields, and orchards. They also usually roost communally with up to 800 other birds! So far it is the only one in our area!
Yellow-billed Magpie - Pica nuttalli
In the morning it likes to chatter from the sunny top of a tree. It is a loud talker, louder than any other bird in the neighborhood! I love hearing it! I am really hoping this magpie sticks around, but I'm not sure how it will survive a snowy winter.
Petroglyphs in the Lakes Basin!
My friends, Rod and Rochelle took me cross-country to a petroglyph site up in the Lakes Basin this week! WOW! It was so exciting! The petroglyphs were shallowly carved and pecked on a horizontal slab of bedrock, right next to a creek bed. There were about 15 different designs on the site! The only other petroglyphs I have seen in the Lakes Basin are the ones in the Lakes Basin Campground, that are accompanied by a USFS interpretive display. Another local area that is known to have petroglyphs is near Hawley Meadows. My friends and I hiked out there to see them, but had to turn back before we found them. Hopefully next time we'll see them!
I asked my friend, local historian/archeologist Hank Meals, about the origin of the petroglyphs. He explains it eloquently in the following paragraphs.
"In the higher reaches of the Feather, Yuba, Bear and American Rivers are symbols pecked into bedrock by ancient hunters and gatherers. They are typically found above 5000 feet with motifs that are distinctive and reoccurring. There are some recognizable elements, such as animal prints, but most are abstract symbols, at least to us. Many of the petroglyph panels are in dramatic settings with expansive views.
There is no way to accurately date the petroglyphs but
occasional artifacts found at the sites date from 4,000 to 1,500 years ago. No
one claims to know what the abstract glyphs mean including contemporary Nisenan
and Washoe people. If, in fact, they do know why should they tell us? Theories
about their meaning include boundary markers, maps or places to conjure, or
summon, hunting luck/magic."
Hank Meals has hiked, photographed, studied, and written about our local area for many years! His knowledge of the area is incredible! He has published several books on the local trails and their history, such as Yuba Trails (1995), Yuba Trails 2 (2001), and The River (2008). He has a blog, yubatreadhead.blogspot.com, in which he shares his experience and knowledge of this area. Check it out! It's fascinating!
Cedar Waxwings - Bombycilla cedrorum
Surprise Visitors!
Late one afternoon I noticed a bunch of birds in a mistletoe clump near the top of a dead cedar tree, eating the berries! They were backlit and hard to indentify. Later, when I looked at the images on my computer, I was surprised to see that they were Cedar Waxwings!!! I have only seen them a few times before in the Spring, eating the local cherries!
It turns out that Cedar Waxwings can be found throughout California during the winter! They travel in flocks, ranging from less than 10 to several 100 in size! Being "frugivores" they exist almost totally on fruit, mainly in the form of local berries. They eat madrone, mistletoe, juniper, mountain ash, hawthorn, dogwood, strawberries, raspberries, serviceberries, and cedar berries. Cedar berries are their main food in the winter, but are not found on cedar trees. They are misnamed. They are actually the berries of the Eastern Red Juniper, which mainly grow on the east side of the Sierra. In summer, Cedar Waxwings supplement their fruit diet with insects and some flowers.
Their name is derived from their preference for cedar berries in winter, as well as the waxy tips of their inner flight feathers. It is suggested that the bright red color of the waxy tips may attract mates. No other function of the waxy tips has been determined! It was so interesting to see them in our neighborhood! I had no idea that they might be around. I'll keep a closer watch this winter!
Chickaree or Douglas Squirrel - Tamiasciurus douglasii
Lately, this little Chickaree has been busy collecting walnuts for the winter, from my neighbor's tree. It is such an acrobat! Usually when it sees me, it stops moving and holds perfectly still. I watched it for several minutes, and it finally moved! It lay down on the branch, perhaps in an attempt to become less visible.
Chickaree or Douglas Squirrel - Tamiasciurus douglasii
I love how its hind toes wrapped around the branch! Their hind legs are double-jointed, which is one of the reasons they're such good climbers!
Convergent Lady Beetles - Hippodamia convergens
The Ladybugs are Back!
Every year 1,000's of these Lady Beetles or Ladybugs converge to mate in our neighborhood. They remain here throughout the winter and return to lower elevations in the Spring, when temperatures warm up. Like most over-wintering insects, they replace any water in their body fluids (hemolymph) with an anti-freeze during the winter. This prevents any frost from forming within their cells and causing damage.
There aren't many predators of ladybugs, as they secrete a noxious fluid that makes them unpalatable. However, my neighbor, Tammy, has watched dragonflies catch them again and again, near her pond! Wow!
Every year 1,000's of these Lady Beetles or Ladybugs converge to mate in our neighborhood. They remain here throughout the winter and return to lower elevations in the Spring, when temperatures warm up. Like most over-wintering insects, they replace any water in their body fluids (hemolymph) with an anti-freeze during the winter. This prevents any frost from forming within their cells and causing damage.
There aren't many predators of ladybugs, as they secrete a noxious fluid that makes them unpalatable. However, my neighbor, Tammy, has watched dragonflies catch them again and again, near her pond! Wow!
Where are the foxes?
The track I posted last week was a Black Bear track.
I found it in a dry lake bed in the Lakes Basin.
Check back next week for the answers to these questions and more!
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