Photo 1 – The Crop – Every day the question is asked “What is the crop?” In short it is a pantry or storage area below the chin that is filled when some birds (not all) eat. In the first photo above the eaglet on the right has a full “crop.” You can see it bulging out. In technical terms, it is an expandable section of the esophagus that is used to store and soften food and regulates the flow of food through the digestive tract.
Photo 2 – On March 3 I posted an article about eagle hearing and ears. In photo 2 above the ear hole on the eaglet in the middle shows clearly just behind its eye. Once its head feathers grow in you will no longer be able to see the ear. Also in photo 2 if you look closely at the eaglet laying down on the right you will notice that the down on its back (see March 18 article about down) is in rows. These rows are called feather tracts. There are 8 major feather tracts on birds that are divided into about 100 groups. These feather tracts are connected by a complex system of nerves and muscles that allow the eagle to control and move its feathers as needed for insulation, preening, flight and all other purposes.
Click photos to enlarge.