Prosopis seed dispersal by mammals in the Monte desert (Argentina).

CAMPOS, C. ; VELEZ, S. ; CAMPOS, V. ; GIANNONI, S.

Montpellier

Simposio; 5th International Symposium- Workshop on Frugivory and Seed Dispersal FSD 2010.; 2010

In the arid areas of Argentina, Prosopis (Fabaceae) plays an important role in the functioning of communities. The fruits of some Prosopis species are indehiscent pods, with a mesocarp rich in sugars and protein and palatable to animals. The aim of this study is to summarize the role of wild and domestic mammals in seed dispersal and seed germination. Small rodents (Graomys griseoflavus, Akodon molinae, Calomys musculinus, Eligmodontia typus, and Microcavia asutralis) remove and hoard fruits and seeds after primary dispersal and can act as predators or dispersers. Non-native mammals (cow, horse, donkey, European hare, wild boar) and native mammals (Dolichotis patagonum, Pseudalopex griseus, Lama guanicoe) are endozoochorous dispersers. The passage through the digestive tract of mammals modifies seed germination capacity and speed, with great variability depending on the particular mammal and Prosopis species involved. Subsequently, seedling establishment and sapling survival are related to defecation sites and to the activity of animals such as cattle. Small mammals and ants also remove seeds from cattle dung, and the importance of each removal group depends on season and on seed availability in the field. Animals constitute an important range of dispersal agents of Prosopis seeds through strategies that can delay or speed germination. This is of great importance in deserts where climate conditions are unpredictable, and the seed must consequently wait for opportune moments.