Response of different-sized herbivores to fire history

Retrieve original file from: http://edepot.wur.nl/121801 High herbivore densities and re-occurring fires are natural phenomenons that determine the structure and functioning of African savannas. Traditional burning practices have been intensified over the past years due to increased herbivore numbers. Insight how animals respond to fire is important to understand ecosystem functioning and for the use of fire as management tool. Until now studies have centred mainly on spatial relationships between herbivores and fires. Very little information exists on effects of temporal fire patterns on herbivore communities. To assess the effect of fire succession on herbivore species greatly differing in body mass we conducted experiments and observational studies on smaller scales and landscape scales. We investigated the response of herbivores on both short-term and long-term succession patterns. Rodent densities were affected by the presence of larger herbivores rather than by seasonal patterns and increased with the absence of large herbivores and increasing vegetation height. Both middle-sized and large herbivore species responded on short-term post-fire patterns with large species being the pioneer species on burnt patches, whereas buffalo was the only species that also responded on long-term post-fire patterns. Our results indicate that larger herbivores in interaction with fire influence rodents by both increasing and prolonging the predation risk they experience in these habitats. Furthermore grazer presence and the amount of rainfall may be two interacting factors that prolong fire patterns in the landscape. Particularly buffalo responded to fire patterns, most likely due to the higher intake levels of digestible plant material and increased forage efficiency. Herbivore response to fire history