The Depression of Reptile Biomass by Large Herbivores

Abstract

I hypothesize that an apparent very low density of reptiles in a wide variety of African habitats is due to exceptional predation pressure on reptiles by a large array of carnivores that are maintained in two ways by the exceptionally large biomass of large herbivores in these habitats. First, there is anecdotal and circumstantial evidence suggesting that some of the regular predators on reptiles may take carrion or other products from big game in times of short supply of regular prey, thereby maintaining higher population densities than would otherwise be the case. Second, there is anecdotal evidence suggesting that regular consumers of large game may take reptiles as the occasion permits. A brief examination of the reptile fauna of eastern and southern Africa, in search of traits expected of a reptile fauna under exceptional predator pressure, reveals little to support or deny this hypothesis. Additionally, but not developed in depth, it is postulated that African large herbivores may substantially reduce reptile biomass through habitat destruction, especially in more seasonal areas where local water sources and riparian vegetation are important to reptiles, their prey, and large herbivores.