Affiliation:
1. MOE Key Laboratory of Biosystems Homeostasis and Protection, College of Life Sciences Zhejiang University Zhejiang China
2. Section for Molecular Ecology and Evolution, Globe Institute University of Copenhagen Copenhagen Denmark
3. Zhejiang Zhoushan Archipelago Observation and Research Station, Institute of Eco‐Chongming, Zhejiang Tiantong Forest Ecosystem National Observation and Research Station, School of Ecological and Environmental Sciences East China Normal University Shanghai China
Abstract
AbstractSeed dispersal by frugivorous birds facilitates plant invasions, but it is poorly known how invasive plants integrate into native communities in fragmented landscapes. We surveyed plant–frugivore interactions, including an invasive plant (Phytolacca americana), on 22 artificial land‐bridge islands (fragmented forests) in the Thousand Island Lake, China. Focusing on frugivory interactions that may lead to seed dispersal, we built ecological networks of studied islands both at the local island (community) and at landscape (metacommunity) levels. On islands with P. americana, we found that P. americana impacted local avian frugivory networks more on islands with species‐poor plant communities and on isolated islands. Moreover, as P. americana interacted mainly with local core birds (generalists), this indicates reduced seed dispersal of native plants on invaded islands. At the landscape level, P. americana had established strong interactions with generalist birds that largely maintain seed‐dispersal functions across islands, as revealed by their topologically central roles both in the regional plant–bird trophic network and in the spatial metanetwork. This indicates that generalist frugivorous birds may have facilitated the dispersal of P. americana across islands, making P. americana well integrated into the plant–frugivore mutualistic metacommunity. Taken together, our study demonstrates that the impact of plant invasion is context‐dependent and that generalist native frugivores with high dispersal potential may accelerate plant invasion in fragmented landscapes. These findings highlight the importance of taking the functional roles of animal mutualists and habitat fragmentation into account when managing plant invasions and their impact on native communities.
Funder
China Scholarship Council
Danmarks Frie Forskningsfond
National Natural Science Foundation of China
Natural Science Foundation of Zhejiang Province
Program for Professor of Special Appointment (Eastern Scholar) at Shanghai Institutions of Higher Learning
Subject
Ecology, Evolution, Behavior and Systematics