Pictured here is a sparrow-sized bird known as the American Goldfinch, Spinis tristis. This member of the Fringillidae family is the only little yellow bird with black wings found in North America. This bird is a male and is undergoing transition from his winter plumage to his breeding plumage. You can see a winter version I photographed in West Texas here. The breast is completely yellow when these birds are in breeding condition and they have a black cap on the top of their heads. You can see in this image that he is not quite there yet.
Every one of these birds I have ever observed is an acrobat. They hang by their feet in whatever position affords them the best approach to the food they are pursuing. You can also see in this photo that the neck plumage is working on becoming yellow and you can see the black wings and tail with white accent stripes. A similar species, the Lesser Gold Finches, would be black from the top of the head to the tail.
Here is another image showing the incomplete yellow coloring of the breast feathers. These images were shot in early April.
While they are foraging, these little fellas have to keep a wary eye out for predators. However, there was another male in the vicinity that made more than one pass at this guy’s head. Either way, it pays to stop now and then and check your situation.