Vertebrate Herbivory and Its Ecosystem Consequences


Herbivory is a process where animals obtain energy and nutrients from vegetative plant parts (leaves, stems, etc.). Herbivory is called grazing, browsing or folivory, depending on the size of the herbivore and the type of plant tissue consumed. The consumption is actually performed by microbes in the digestive system. The role of the animal is to prepare the material and to provide a good environment for the microbes. This requires specializations, making herbivores a distinct animal group. This article focuses on consequences of herbivory by vertebrates. Vertebrate herbivory can change forests to heathlands or grasslands and influence the composition and species richness of the herbaceous vegetation.

Keywords: competition; consumption; plants; species richness; vegetation

Figure 1.

Tall, scattered trees in subalpine (upper panel, from French Alps) and subarctic (lower panel, from northern Norway) landscapes, shaped out by centuries of intense herbivory by cattle, sheep and goats (upper panel) or reindeer (lower panel). Photos were taken by Lauri and Tarja Oksanen.

Figure 2.

The contrast between summer range, subjected to periodically intense reindeer grazing in late summer (right) and lightly grazed autumn range (left) on the mountains of northern Norway mountains. The fence across which the picture is taken is 40 years old. Photos were taken by Lauri and Tarja Oksanen.

Figure 3.

Two variants of moist and nutrient‐rich low alpine meadow. The left panel shows an area abandoned 40 years ago when the border fence of the legal summer range was constructed; the right panel is taken from the intensely grazed summer range. Photos were taken by Lauri and Tarja Oksanen.

Figure 4.

The vegetation of a moist and nutrient‐rich low Arctic willow scrubland in the mainland (left) and of an initially similar habitat on an isolated island, where gray‐sided voles were introduced in 1991 (right; photo taken in July 2008). Photos were taken by Lauri and Tarja Oksanen.



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How to Cite close
Oksanen, Lauri, and Olofsson, Johan(Mar 2009) Vertebrate Herbivory and Its Ecosystem Consequences. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1002/9780470015902.a0003283]