Work

Effects of defaunation of large seed dispersers, habitat loss and fragmentation on the population expansion of a tropical palm

Year: 2025

Type: article

Abstract: Content Habitat degradation and hunting are the main causes of the reduction in fauna diversity, richness, and biomass, characterizing defaunation. Large animal species are the most affected by this process, compromising ecosystem services such as seed dispersal. Objectives We evaluated the effects of the nonrandomdefaunation of large seed dispersers, habitat loss and fragmentation on the expansion dynamics of tropical palms (Euterpe edulis) populations. Methods We modeled the spatial dynamics of the species via RangeShiftR in landscapes with different degrees of habitat percentage and fragmentation, simulating two distinct scenarios: nondefaunated, with a complete assembly of seed dispersers, and defaunated, with an impoverished assembly of large frugivores. Then, we developed linear regression models, and the best model was selected using the Akaike information criterion. Results Habitat loss, fragmentation, and defaunation synergistically affect the abundance and density of palm hearts. Furthermore, the interaction effect between defaunation and habitat percentage was significant, indicating that in nondefaunation scenarios, the abundance and occupation of palm hearts increase substantially. Additionally, habitat loss has a greater effect on population expansion than fragmentation, which has a lower predictive power. Conclusion These results help addressthe individual and synergistic effects of defaunation, habitat loss and fragmentation on the population expansion of palm hearts. Our models contribute to the strategic planning of actions aimed at the conservation of palm hearts, highlighting habitat loss as a central point in allocating efforts for the protection of this species, as well as the importance of considering fauna data in estimates of the population expansion capacity of plant species.

Source: Landscape Ecology

DOI: 10.1007/s10980-025-02077-1