Traits of perch trees promote seed dispersal of endemic fleshy-fruit species in degraded areas of endangered Mediterranean ecosystems

Abstract

The presence and attributes of perch trees in degraded areas may promote seed dispersal. We evaluated the effect of the distance from remnant forest fragments on seed rain of different fleshy-fruit tree species and examined whether the seed rain is favoured by some traits of the perch trees (Acacia caven), such as canopy diameter and tree height. The study was carried out in two localities of central Chile with extensive “espinales” adjacent to remnant fragments of sclerophyllous forest. We installed 210 seed traps under the same number of A. caven trees along 10 transects in the two study areas. We set up the seed traps between 1 and 100 m away from forest fragments. We found a significant negative relationship between seed rain and distance. We also found a positive relationship between seed rain and the height and canopy diameter of the perch tree. Our results suggest that different woody species are able to disperse into the espinal, and that bigger A. caven trees are better perches than smaller individuals. We propose that at distances up to at least 100 m from forest fragments, seed availability does not limit natural regeneration into espinales.