Lingua Corax

Last year, was the first time I saw Common Ravens (Corvus Corax) in the Arboretum. I was uncertain if they were just passing through, vacationing, or homesteading. This year they nested, raised young, and appear to have taken permanent possession of the Arboretum, Interlaken Park, and the surrounding neighborhoods. 

June was the last time I remember seeing the adults feeding young. Since then, I have certainly seen less of the ravens. However, if I include hearing their voices, I would say the total number of encounters has remained fairly stable.

Lately, I have not seen more than two ravens at a time. I suspect the young have left home and moved out on their own. When the adults are visible it tends to be in brief gliding flyovers which decrease the photographic opportunities.

Last month, when the smoke was really bad I generally stayed indoors. Cabin fever was driving me up the walls and halfway across the ceiling, metaphorically speaking. Finally, I decided to test wearing multiple masks at once. I was hoping the combination would help. A short walk quickly convinced me that additional masks were still inadequate.

However, during my brief foray, I heard a flock of crows raising a ruckus. The band of irritable corvids sat on the treetops barely in view below the thick gray skies. Their irritation seemed somehow appropriate even though I could not see the source of their indignation. A few moments later, I heard the calm, confident 'grawk' of an adult raven as it flew past with virtually total indifference for the crows. I watched its slow stately wingbeats as it disappeared into the Arboretum. Its mate followed the same path through the smoke-filled skies while responding in kind. Hearing the sounds of their voices and watching them pass made the hair on my neck stand up. 

On Friday, I recorded one of them making the same type of sound. 

I have just started reading a book called "The Bird Way" by Jennifer Ackerman. The initial section is about bird talk which probably helped inspire this post. There seems to be some amazing progress in understanding what certain birds are communicating. Although, I do not remember any discussion of ravens.

Birds of the World (BOTW) suggests there is much to learn about ravens and their communications. The previous vocalization is referred to as a Demonstrative Call in BOTW. It is apparently used to declare territory and location.

Before hearing a Raven on Friday, I was surprised by a Douglas Squirrel approaching me along the top of the Broadmoor fence. I have been seeing the small reddish squirrels occasionally for the last month but our encounters have all been brief. Often, I hear them without seeing them at all. When I do see them they quickly scurry away. This one's "friendliness" made me wonder if someone had been feeding it. I hope not. The native Douglas Squirrels have enough challenges without developing a misplaced trust of humans.

Earlier in the month, I saw two of them chasing each other around a tree. Seeing two at once was quite exciting. After living next door for over thirty years, and having never seen a native squirrel in the area until the last year, it certainly sparked a sense of hope to encounter a pair of them.

Lately, I have noticed the fur on the Douglas Squirrels has been changing. They seem to be wearing autumn colors with a reddish-brown upper coat and an orangish-red underbelly. 

This contrasts quite dramatically with the one that I saw in June. It had more of a gray-brown upper coat and a rather pale belly and chest.

Regardless of the time of year, the Douglas Squirrels are significantly different than the non-native Eastern Gary Squirrels (EGSQ). The most obvious difference is the EGSQs have white underbellies. They are also larger, grayer, have fluffier tails, and never have tufts on the top of their ears.

Sadly, the nonnative EGSQs usually produce two litters a year while the Douglas Squirrels normally produce only one. We will just have to cross our fingers and hope that the native squirrels can make a come back.

 

After the squirrel left, I heard a very odd sound coming from a nearby tree. As I slowly made my way closer I came to suspect it was one of the ravens. Their vocal capabilities are virtually limitless so hearing an odd call or song is not totally surprising.

I was encouraged to find my assessment of the sound was correct. The following video contains the sound the raven was making. I believe this is the Knocking sound discussed in BOTW. It says the knocking sound is only uttered by females. Plus, it says it, "Often occurs during duets between mated pairs after territorial defense or during courtship" (See Citation Below)

After a bit, the raven circled around and began a different type of sound. This one I have heard before. I call it the "Pitch Drop" call. I do not see any reference to it in BOTW. A week or so ago I heard one them making this call late in the afternoon. After sitting and calling for a few minutes a second raven appeared and set down on the branch right beside it. A moment later, they flew off in the same direction. I am wondering if this call means something like "Hey, Honey, Where are you?" e.g. a Contact Call. See what you think?

The day before yesterday, my friend Tom Cotner and I heard a raven make the "Water Drop" sound as it passed overhead. Click Here and then scroll down to the last recording to hear a similar sound on All About Birds. Both times I remember hearing this sound the birds were flying away from a body of water. I suppose that was just a coincidence. Although, curiously BOTW says, "In a contextual analysis of raven communication, calls were shown to indicate more about what was not going to happen next than they did about what was going to happen next..."

The only other sound I remember the raven's making happened last Spring. When a Red-tailed Hawk apparently accidentally approached their active nest. The raven on guard duty started making a clucking sound. The speed and volume of the sound grew faster and louder the closer the hawk got. When the hawk got within a hundred feet or so the raven left its perch and gave chase. The hawk wanted none of it and quickly left the area. BOTW describes this sound as a Predatory Alarm.

Yesterday, after all of the noise subsided and the raven disappeared I headed for home. I had not gone far when I heard the sound of a raven's wingbeats passing overhead. We were inside the Arboretum canopy. With all the trees, branches, and swift movement there was no chance for photos. Ultimately, I did notice there was a second bird involved with the raven. 

It was a smaller brown flash chasing after the raven. They circled multiple times, Clearly, the trailing bird was more agile. It flew behind and above while switching rapidly from one side to the other. The raven worked hard to stay in the lead. They circled and stopped multiple times. It seemed as if they were playing chase. Finally, I tracked them back to the area where they were occasionally stopping. The raven landed on an upper branch of a Bigleaf Maple. The smaller bird perched about 10 feet away. The raven, while looking directly at the accipiter, raised its wings the smaller bird decided to retreat.

It was apparently a first-year Cooper's Hawk. The graduated length of the tail feathers clarified that it is a Cooper's Hawk - not a Sharp-shinned Hawk. Its size relative to the raven made me suspect it was a female. The vertical striping on the chest says it is either in its first or second year. Since, I saw a second-year losing its stripes a few months ago and these stripes look fresh, clean, and fully complete I suspect this is a bird that hatched out this Spring.

After a few minutes, the Cooper's Hawk flew away to the northwest. The raven looked around for a bit before moving up and away into a nearby Douglas Fir tree.

I circled around and tried to peer through the intervening branches. I finally caught a parting view of the raven. Although it is difficult to make out, below and slightly to its right was its mate. The pair sat there and took turns preening for quite some time. I wonder if they often spend the night in places like this. They were hidden from above by the upper twenty-five percent of the canopy and at 75 to 100 feet in the air they were hidden from below. It is hard to imagine a safer location for ravens to sleep.

Have a great day on Union Bay...where nature lives in the city and Black Birders are welcome!

Larry

Recommended Citation

 Boarman, W. I. and B. Heinrich (2020). Common Raven (Corvus corax), version 1.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.comrav.01

Going Native:

Without a well-funded Environmental Protection Agency, it falls to each of us to be ever more vigilant in protecting our local environments. Native plants and trees encourage the largest diversity of lifeforms because of their long intertwined history with our local environment and native creatures. I have been told that even the microbes in the soil are native to each local landscape. I hope we can inspire ourselves, our neighbors, and local businesses to respect native flora and to support native wildlife at every opportunity. I have learned that our most logical approach to native trees and plants (in order of priority) should be to:

1) Learn and leave established native flora undisturbed.

2) Remove invasive species and then wait to see if native plants begin to grow without assistance. (If natives plants start on their own, then these plants or trees are likely the most appropriate flora for the habitat.)

3) Scatter seeds from nearby native plants in a similar habitat.

4) If you feel you must add a new plant then select a native plant while considering how the plant fits with the specific habitat and understanding the plant's logical place in the normal succession of native plants.

My intention in my weekly post is to include at least one photo each week and visually challenge us to know the difference between native and non-native lifeforms. 

By the way, my friend Tom Brown pointed out that the application named 'Wildflower Search' is extremely helpful. Click on the highlighted link to see for yourself.

Which species of trees is this? The winged seeds are a clear hint. Is it native to Union Bay?

 

 

 

Scroll down for the answer.

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Vine Maple: It is a relatively small native maple tree, generally found in the understory. It spreads its leaves to collect as much of the dappled light, that filters down between the surrounding giants, as possible.

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The Email Challenge:

Over the years I have had many readers tell me that Google is no longer sending them email announcements regarding my posts. Even more frustrating when they go to 're-sign-up', hoping that will enable them to once again start receiving the announcements, they get a message which says 'Sorry, you are already signed up.' Google has not responded to my requests for help with this issue. 

My functional workaround is to set up my own email list and each week I manually send out a new post announcement. If you are experiencing the issue and would like to be added to my personal email list please send me an email requesting to be added. Thank you for your patience!

My email address is: LDHubbell@Comcast.Net

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Here are a few May photos for those who persevere: