Raven Sightings....

I'm in contact with a mentor from my college days in the early 1970s who now resides miles away from me in the Pacific Northwest region of the United States. Even before he retired, he admitted he enjoys "birding" and seeing some of his photos has been a wonderful thing for me, as he posts them from time to time (I have several friends and acquaintances who have developed great skill in nature photography, and I am envious.
 He especially seems fond of owls, and admittedly, it's been very rare for me to see an owl in the area where I live, though I do.hear them occasionally, and catch a glimpse of one in a tree looking wise (and probably for some hapless critter to wander by) but such sightings are not a common occurrence.
While at my place of employment the other day in a large city, I was sitting in the office of the psychiatrist whose office space I share when he is not in, which contains a large, upside down "U" shape window looking out onto a green area which slopes downward to a large culvert.
     Preparing for the arrival of my first client, I happened to look up after hearing a loud rapping at the window. Shades of Edgar Allen Poe! I'm guessing what initially attracted the bird, which appeared to be what I later identified as a Common Raven (see photo I found online)--it was a very large bird, and his rapping on the glass I surmised was due to the outer surface of the glass being a mirror reflective type. I say "he," but of course, not being really an expert, "he" could easily have been a "she." I never heard it make a sound, but shortly after its arrival, another similar bird appeared and they wandered along the ground outside the window, no doubt looking for some tasty bugs or other morsels.
   While looking up info later about my feathered visitors, I found that Ravens are the largest of the dark-winged birds, with crows being in the mid-range and blackbirds the smallest. The true blackbird has the best melody from the sources I read--if you're familiar with a song Sir Paul McCartney sang solo when he was with The Beatles, you have a sample of the true blackbird's song within that song.
   Given the location of my place of employment, though there are several office buildings within the same area, the building containing my office (and employer) is set further back from busy roads nearby, with shrubs surrounding the building, (often nesting places for ducks) as well as large stately oak trees, the aforementioned culvert, and a generally quiet setting. It has several types of "wildlife" who show up from time to time in addition to these two huge ravens.