A Review of Endozoochorous Seed Dispersal by Herbivores and Its Potential Effect on Seed Germination

M-ECOL

إنجليزي. Endozoochorous seed dispersal by large herbivores provides a possible aid for ecologicalrestoration of plant communities. This review thesis determines and analyses seed dispersal andseed germination via sheep, cattle, horse, rabbit, deer and herbivore birds dung in differentecosystems. Large amounts of viable seeds of different plant species have been found inherbivore dung in previous studies; however which species produce seeds that can survive andgerminate after ingestion by herbivores is still not well understood.According to my review study out of 31 plant families Poaceae and Cyperaceae are the mostcommon plant families which are dispersed by all six herbivores dung in different ecosystems.Cattle are among the most seed disperser as compared to other herbivores, while herbivores birdsdisperse the seeds at long distances then other herbivores due to migration over longer distances.Seed germination success rate depends on initial mastication and rumination by the herbivoresrather than mean retention time.Those plants which have smaller seeds are more likely to disperse by herbivores dung than theplants which have large seeds. And the seed passage through the animal gut may affect thefraction of seed germination it may costly if inhibit the process of seed germination by reducingthe mechanical protection of seed coat and this cost can be offset if animal deposit the seeds invery favorable microhabitats. This study also indicates that there are potentially high costs toendozoochory that have to be balanced against the benefits of long-distance dispersal by largeherbivores.Key words: Endozoochorous, Seed dispersal, Poaceae, Cyperaceae, Herbivores, Mastication,Rumination, Germination, Ingestion, Ecosystem.