Seed removal by different functional mammal groups in a protected and grazed landscape of the Monte, Argentina

CONA, M.I.; CLAUDIA M. CAMPOS; MIGUEL F.

SEED SCIENCE RESEARCH

CAMBRIDGE UNIV PRESS

Lugar: Cambridge; Año: 2017

0960-2585

Mammal species contribute in different ways to seed dis-persal effectiveness, acting as endozoochorous disper-sers, scatter-hoarders and seed predators. Seedremoval by these functional mammal groups could beaffected by anthropogenic drivers, such as grazing man-agement, a common practice in drylands. We evaluatedremoval of seeds from a native tree species (Prosopisflexuosa) by terrestrial wildlife mammals with differentfunctional roles, on grazed and ungrazed sites and at dif-ferent times during the fruiting period of Prosopis. Weoffered Prosopis fruits, each containing 15 seeds, toanimals and used camera traps to identify the speciesremoving them. We obtained the number of seedsremoved (1 fruit removed = 15 seeds removed) by eachanimal species and each functional group. Native anddomestic mammals removed 65.4% of the total seedsoffered; 69.5% of offered seeds were removed from thegrazed area and 61% from the ungrazed site.Considering removal times, 64.25% of offered seedswere removed during the beginning of the fruitingperiod of Prosopis and 67% towards the end of thisperiod. Small mammals acting either as seed predators(Graomys griseoflavus and Akodon dolores) or scatter-hoarders (Microcavia australis) were the functionalmammal groups removing the highest amount of seeds.Seed predators removed more seeds from the ungrazedsite, whereas the scatter-hoarder did so at the grazedsite. In the ungrazed area, it would be important toensure habitat heterogeneity in order to improve seedremoval by functional groups that disperse seeds, suchas endozoochorous dispersers and scatter-hoarders.