Grazing (behaviour)

Grazing is a method of feeding in which a herbivore feeds on low-growing plants such as grasses or other multicellular organisms, such as algae. Many species of animals can be said to be grazers, from large animals such as hippopotamuses to small aquatic snails. Grazing behaviour is a type of feeding strategy within the ecology of a species. Specific grazing strategies include graminivory (eating grasses); coprophagy (producing part-digested pellets which are reingested); pseudoruminant (having a multi-chambered stomach but not chewing the cud); and grazing on plants other than grass, such as on marine algae. Grazing's ecological effects can include redistributing nutrients, keeping grasslands open or favouring a particular species over another. Many small selective herbivores follow larger grazers which skim off the highest, tough growth of grasses, exposing tender shoots. For terrestrial animals, grazing is normally distinguished from browsing in that grazing is eating grass or forbs, whereas browsing is eating woody twigs and leaves from trees and shrubs. Grazing differs from predation because the organism being grazed upon may not be killed. It differs from parasitism because the two organisms live together in a constant state of physical externality (i.e. low intimacy). Water animals that feed by rasping algae and other micro-organisms from stones are called grazers–scrapers. Graminivore Graminivory is a form of grazing involving feeding primarily on grass (specifically "true" grasses in the Poaceae). Horses, cattle, capybara, hippopotamuses, grasshoppers, geese, and giant pandas are graminivores. Giant pandas (Ailuropoda melanoleuca) are obligate bamboo grazers, 99% of their diet consisting of sub-alpine bamboo species. Rabbits are herbivores that feed by grazing on grass, forbs, and leafy weeds. They graze heavily and rapidly for about the first half-hour of a grazing period (usually in the late afternoon), followed by about half an hour of more selective feeding.