Seed dispersal by different-sized herbivores in rangeland habitats of central Iran (Case study: Esfahan Kolah Ghazi National Park)

The present research was aimed to assess the potential seed dispersal of plant species by different-sized herbivores of hare (Lepus capensis), Persian gazelle (Gazelle subguttrosa) and wild goat (Capra aegagrus) in rangeland habitats of Kolah-Ghazi National Park in Esfahan. Ten freshly pellet groups (dung sample) of herbivore species were randomly collected in each of selected habitat sites during spring and autumn growing seasons (April to June and October to November). Seed content of dung samples were determined in greenhouse germination experiments over a period of 8 months. In total, 1637 seedlings from 60 plant species (19, 43 and 45 seed species in dung samples of cape hare, Persian gazelle and wild goat, respectively), mainly annual with attractive inflorescence and small seeds were recorded in dung samples of the three herbivore species. Seed content found in the all herbivores dungs were differed significantly, in addition, numbers of dispersed seedlings were correlated to herbivores size. However, the observed differences in dung seed density of herbivore species was not related to their sizes; so the highest and the least number of seeds were recorded in dung samples of wild goat and Persian gazelle, respectively. Given that most of plant species recorded in the Park regenerate by seeds, and that seeds of different plant species dispersed by herbivore species, seed dispersal via dung of different-sized herbivores may play an important role in vegetation conservation and dynamics of these rangelands habitats, only if required environmental factors met. While increasing knowledge of plant seed dispersal, results of the present research can be specially applied in managing country’s protected ecosystems and rangeland habitats.