Supporting data for Mendes et al 202X The urbanisation of seed dispersal networks

Urbanisation is rapidly expanding, affecting the composition of wild communities and creating novel ecosystems worldwide. Seed dispersal is key for ecosystem persistence, particularly in fragmented landscapes, however, generalisations regarding the impacts of urbanisation are still hindered by the lack of studies encompassing the urban matrix. We reconstructed the seed dispersal networks in natural forests and urbanized habitats in Tenerife Island to explore the effects of urbanisation on seed dispersal. For one year, we conducted frugivory observations and identified seeds in animal faeces in the thermophilous vegetation belt, where anthropogenic pressure is highest. The forest network comprised 150 interactions between 83 plant and 18 animal species, while the urban network presented 89 interactions between 41 plant and 9 animal species. The urban matrix supported a lower richness of fleshy-fruited plants and dispersers. We found that urbanisation simplified seed dispersal networks, reducing interaction diversity. Importantly, novel interactions dominated the urban seed dispersal network, with exotic plants deeply integrated by interacting with native frugivores, accounting for 61% of the interactions (vs. 15 % in the forest). Eight frugivores (42%) maintained the functional connectivity between these habitats; likely facilitating the spread and invasive species from the urban areas into the forests due to their generalist diets. Six dispersers (32%) completely avoided urbanized habitats for which the later represent a particular stringent form of habitat fragmentation, with likely consequences for long-term plant genetic diversity. These findings highlight the need for sustainable urban planning and active stakeholder engagement to conserve the seed dispersal service.