Effects of land-use changes on the distribution and use of Ficus species by frugivores in the urban mosaic landscape of Durban, KwaZulu-Natal, South Africa.

Abstract

Land-use change is one of the greatest threats to biodiversity. Over the years, these changes potentially reduced ecosystems capacity to sustain food production for vertebrates. Ficus (figs; Moraceae) is one of the largest plant genera in lowland tropical rainforests, with more than 850 described species distributed worldwide and 124 species in Africa. Fig trees occupy diverse habitats and attain a wide range of growth forms, including large woody climbers, hemiepiphytes, trees, and shrubs. Over 1200 species globally feed on Ficus fruits and over 10% of the world’s birds and 6% of mammals consume figs, making them the most widely consumed plant genus. Fig-fruiting phenology is such that they are generally available during periods of food scarcity and may influence entire faunal communities, particularly as a dry season staple food. Therefore, it is a well-known key fruit resource component in tropical forests and one of the most important genera sustaining numerous frugivores across different landscapes. In a mutually beneficial relationship, the plants also benefit from seed dispersal by frugivores taking seeds away from the parent plants to locations of fewer pathogens, enhancing germination and plant recruitment. This study was concerned with the interactions between fruit-producing plants and fruit-eating animals across an urban mosaic landscape in KwaZulu-Natal, South Africa. Specifically, the study focused on Ficus spp. of conservation importance and keystone species. Despite the critical role that figs play in many frugivores' ecology, there is relatively little information on the distribution and diversity of Ficus species along forest-urban gradients in relation to different land uses and frugivore foraging behaviours in the study area. Details of the relationships between different components of the frugivore-seed disperser and different fig species also remain unclear. Thus, this study enhances the understanding of the role of birds, bats and other mammals in seed dispersal, germination, and the effect of land-use changes on fig-frugivore interactions, which is critical for informing conservation and management strategies.