The heads in this example are nodding so I had a good look at photos of Nodding (Musk) Thistle to see if this was Nodding Thistle. Nodding Thistle photos show the flowers on mostly naked stalks. On the photographed plant, there were many thorns on the stalk.
To complicate matters, Bull Thistle (Cirsium) and Nodding Thistle (Carduus) belong to different families.
Species list: mallard, ring-billed gull, mourning dove, hairy woodpecker, downy woodpecker, great crested flycatcher, barn swallow, blue jay, black-capped chickadee, white-breasted nuthatch, red-breasted nuthatch, gray catbird, American robin, cedar waxwing, red-eyed vireo, common grackle, northern cardinal, American goldfinch, song sparrow. (19 species)