Young fish have a dusky vertical bar on the caudal peduncle which fades with increasing age. Molar-like grinding surfaces characterize the middle rows. Common carp prefer warm water, either standing or with sluggish flow. They are most abundant in large rivers, man-made lakes and natural lakes where there is abundant, soft organic matter on the bottom. Carp adapt better than most fish species to pollution caused by sewage or agricultural run-off.
Carp are omnivorous feeders, taking both vegetable and animal matter in their diet.
Aquatic insects, crustaceans, and small mollusks make up the bulk of their forage. They are a nuisance in shallow, weedy habitat where their activity creates high turbidity in otherwise clear water. For this reason, carp have a limited use in nuisance aquatic vegetation control programs. Spawning occurs from mid-April through June when the adhesive eggs are scattered in the shallow water over vegetation, debris, logs or rocks. Splashing carp, with their backs out of the water, may be observed in shallow waters during spring.