This species is omnivorous, feeding on aquatic crustaceans, insects, worms, aquatic plants, algae and seeds (2). Its feeding technique, of grubbing around in the sediment and straining food from the mud, has caused problems in areas where the carp has been introduced. As well as uprooting submerged vegetation, it also increases the cloudiness of the water, which can have detrimental effects on native wildlife (2) (6). In temperate waters, spawning take place during the summer in patches of weeds. A number of males pursue spawning females in the race to fertilise the eggs as they are shed into the water. The sticky yellowish coloured eggs attach to vegetation, and are not guarded by the parents (2). A typical female can lay over a million eggs in one breeding season (2). By gulping air at the surface, the carp is able to tolerate periods when oxygen levels in the water fall (2). In winter, individuals go into deeper waters which tends to be somewhat warmer than shallow water (2).