I had the most trouble with the beak: I could see the shape but not draw it and as you can see, erased several times. I hope the sketching gets easier as we go through the course.
The photo is a captured moment, and it was a luxury to draw from a still image like this. Yellow warblers in the field do not sit still! I did not focus on the tree branch at all although in the field that in itself would be something to note. I found it interesting the way the bird's toes curled around the branch. The rear-facing toe gripped the branch while the front-facing toes almost seemed loose with the nails not touching the branch. Again, one would never notice this in the field but a photo gives some time to study the image and note feather textures and the like.