Crop (anatomy) Crop (anatomy) A crop (sometimes also called a croup or a craw, or ingluvies) is a thin-walled expanded portion of the alimentary tract used for the storage of food prior to digestion. This anatomical structure is found in a wide variety of animals. It has been found in birds, and in invertebrate animals including gastropods (snails and slugs), earthworms, leeches, and insects. Cropping is used by bees to temporarily store nectar of flowers. When bees "suck" nectar, it is stored in their crops. In a bird's digestive system, the crop is an expanded, muscular pouch near the gullet or throat.
Hawking (birds) for certain kinds of aerial insect as a food source seems to correlate with gregarious or colonial behavior versus territoriality. For birds that take advantage of swarming insects, which are by nature found in local concentrations, colonial breeding can be a successful strategy. An example is the cliff swallow of western North America. Its relative the barn swallow hunts larger, non-swarming insects, and is more solitary. Certain neotropical tyrant flycatchers will join mixed-species foraging flocks, as will some Asian drongos. Such flocks stir up flying insects, which can then be picked off in quick sallies. Hawking (birds) Hawking is a