Causes and consequences of migration by large herbivores

摘要: Many populations of large herbivores migrate seasonally between discrete home ranges. Current evidence suggests that migration is generally selected for as a means enhancing access to high quality food and/or reducing the risk predation. The relative importance these alternative selection pressures should depend on demographic circumstances facing given population. Seasonal also has important implications structure and dynamics herbivore communities. Migrants tend be regulated by availability, while residents predators As result, migrants often outnumber considerable margin - pattern seen in several tropical temperate ecosystems. Differences mode regulation could imply competition resources will weak purely resident assemblages, but strong communities dominated migrants. Continual grazing can sometimes lead degeneration vegetation, systems supporting are apparently more resilient. This implies have an impact long-term persistence plant-herbivore systems, particularly areas with slow rates vegetation regeneration.