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Overgrazed area, by native fauna in western New South Wales, in the upper right corner.

Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature reserves. It can also be cause by immobile, travel restricted populations of native or non-native wild animals.

It reduces the usefulness, productivity, and biodiversity of the land and is one cause of desertification and erosion. Overgrazing is also seen as a cause of the spread of invasive species of non-native plants and of weeds. It is not cause by nomadic grazers in huge populations of travel herds, i. e. the American bison of the Great Plains,[1][2] or migratory Wildebeests of the African savannas,[3] nor by holistic planned grazing.[4]

Preventing overgrazing[edit]

Preventing Man-made Overgrazing
Huge herd of migratory Wildebeest in Masai Mara during the Great Migration

Sustainable grassland production is based on grass and grassland management, land management, animal management and livestock marketing. Grazing management, with sustainable agriculture and agroecology practices, is the foundation of grassland-based livestock production since it affects both animal and plant health and productivity. There are several new grazing models and management systems that attempt to reduce or eliminate overgrazing like Holistic management[5][6] and Permaculture[7][4]


One indicator of overgrazing is that the animals run short of pasture. In some regions of the United States under continuous grazing, overgrazed pastures are predominated by short-grass species such as bluegrass and will be less than 2-3 inches tall in the grazed areas. In other parts of the world, overgrazed pasture is typically taller than sustainably grazed pasture, with grass heights typically over 1 meter and dominated by unpalatable species such as Aristida or Imperata. In all cases, palatable tall grasses such as orchard grass are sparse or non-existent. In such cases of overgrazing, soil may be visible between plants in the stand, allowing erosion to occur, though in many circumstances overgrazed pastures have a greater sward cover than sustainably grazed pastures.

Rotational grazing[edit]




Ecological impacts[edit]



North America - United States[edit]




Economic theory[edit]

Main article: Common land

Overgrazing is used as an example in the economic concept now known as the Tragedy of the Commons devised in a 1968 paper by Garrett Hardin.[9] This cited the work of a Victorian economist who used the over-grazing of common land as an example of behaviour. However It should be noted that Hardin's example could only apply to unregulated use of land regarded as a common resource.


Africa-Sahel region[edit]

Main article: Sahel


Overgrazing does not necessarily mean total denudation of the land. Overgrazing can also occur with native species. In the Australian Capital Territory, Australia the local government, in 2013, authorised the culling of 1455 kangaroos due to overgrazing.

Further reading[edit]



  1. ^ Laduke, Winona (1999). All Our Relations: Native Struggles for Land and Life (PDF). Cambridge, MA: South End Press. p. 146. ISBN 0896085996. Retrieved 30 March 2015. 
  2. ^ Duval, Clay. "Bison Conservation: Saving an Ecologically and Culturally Keystone Species" (PDF). Duke University. Retrieved April 13, 2015. 
  3. ^ In balance with, and accompanied by, prides of keystone predators.
  7. ^ West Virginia University Extension Service Overgrazing Can Hurt Environment, Your Pocketbook Ed Rayburn. 2000.
  8. ^ C.Michael Hogan. 2009. Overgrazing. Encyclopedia of Earth. Sidney Draggan, topic ed.; Cutler J. Cleveland, ed., National council for Science and the Environment, Washington DC

External links[edit]