Fugivores birds as suppliers of seed dispersal service in temperate ecosystems: seeding thought whole landscape?

GARCÍA, D; ZAMORA, R; AMICO, GC

Praga, República Checa

Congreso; 2do European Branch of Society for Conservation Biology; 2009

Seed dispersal by animals is considered to be a pivotal ecosystem service, contributing to the dynamic and recovery of vegetation in both pristine and degraded habitats. Despite this importance, there is a need of geographically comparative studies about the role of seed dispersers as service providers in relation to human-caused landscape heterogeneity. We evaluate the seed dispersal service supp lied by frugivorous birds at three different temperate ecosystems: the Cantabrian mountain forest (N Spain), the Mediterranean mountain shrubland (S Spain), and the Patagonian temperate forest (S Argentina). We demonstrate that the abundance of frugivorous birds represents by itself a good bio-indicator of seed dispersal magnitude, irrespective of the site, habitat structure and fruit resource availability. Nonetheless, habitat features and fruit availability always explain a large portion of the variability "in seed dispersal pattern in all studied ecosystems. Birds acted as mobile links for the seed dispersal function across the landscape, since they connected patches´ of different degrees of degradation and /or habitat quality via the deposition of seeds. The spatial configuration of original patches, providing dense woody cover and fruits, as well as the structural features of the degraded matrix, seemed crucial for seed dispersal connectivity through the whole landscape.