Effects of forest fragmentation on the oak-rodent mutualism

TERESA MORÁN LÓPEZ; MIGUEL FERNÁNDEZ; CESAR LUIS ALONSO ; DULCE FLORES RENTERÍA; FERNANDO VALLADARES ROS; MARIO DÍAZ

OIKOS

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2015

0030-1299

Land-use changes are expected to affect plant?disperser conditional mutualisms through changes in animal behavior.We analyzed the oak?rodent conditional mutualism in Mediterranean fragmented forests at two climatically differentlocations. We quantified fragmentation effects on seed dispersal effectiveness and assessed if such effects were due tochanges in habitat structure and intraspecific competition for acorns in fragmented areas. Fragmentation decreased coverfrom predators within mouse territories as well as intraspecific competition for acorns. This resulted in lower dispersaleffectiveness in small forest fragments. Globally, habitat structure was the main driver in mouse foraging decisions. Insmall fragments, low shelter availability precluded mouse movements, leading to short mobilization distances and lowcaching rates. However, as the proportion of cover from predators increased, mice were able to modulate their foragingdecisions depending on intraspecific competition for acorns, resulting in higher dispersal quality. In addition to fragmentationeffects, delayed breeding in the southern locality caused lower number of rodents during the dispersal season, whichreduced acorn mobilization rates. Our study shows that seed dispersal patterns in managed systems can be analyzed as theresult of management effects on key environmental factors in dispersers? foraging decisions.