Ornithological art - A mystery

I am the very happy owner of a new mystery piece of Avian art. I found this piece on eBay and snatched it up as soon as I randomly happened upon it and confirmed that it was indeed an original painting. A definite mystery, but many great elements appealed to me immediately, so I decided, despite knowing nothing about the piece, its history or the artist that it was worth submitting an offer. The field notes in the left corner are very hard to make out, especially being that the quality of the scan provided by the seller is very poor. I will post that scan here, but I will try and replace it with a better one once I have the painting in hand. It is a Guianan Cock-of-the-Rock, a fabulous lekking species from nothern South America, for those of you that don't recognize it. The painting appears to me...and I hope that I am right, to be a sketch prepared in the field. The main portrait in color is beautiful, but I think the parts that appealed to me the most are the sketches along the sides of the piece. The two studies of the birds unique feet are great. The view of the bird in display posture, fluffing up its fabulous nuptial feathers is great, but I think the part that grabbed me the most is the superb head on view sketch on the right side. I am always so attracted to artwork which depicts a bird from a more interesting angle, really capturing what it was like to see that Cock-of-the-Rock face on, right there inside the lek, where the artist must have been to capture such a view.
Ok, herein lies a mystery that I'd like to solve. Does anyone recognize anything about this painting which may lead you to conclude who the mystery artist is? Please comment if you have any thoughts at all. I am in the process of trying to obtain ANY background about the piece from the seller, but so far I have heard nothing, and I fear that there may unfortunately be nothing to tell. I have no idea about its age even, although I will be able to draw some inferences when I see the paper. For now, please share any thoughts or impressions. An update, with any new info, a better scan and a detailed look at the notations will be posted later.

*UPDATE*
Disappointingly I must report that my great find is less great than I had hoped. I received the Cock-of-the-Rock piece today and it is nothing more than a print. I asked the seller explicitly if the piece was an original painting, and the answer was yes. There was a brief glimmer of excitement as I took it out of the package, until I looked closer and saw the poor resolution to the edges of the piece...plus it just didn't pop like a real painting would, even one that was older and possibly a bit faded.
I have communicated with the seller and he is willing to refund me, but I would lose the shipping...both ways. I am trying to decide what to do. It is a nice image, just not at all the same as if it were a painting.