DOI: 10.5061/dryad.m20hf10
title: Data from: Large frugivores matter: insights from network and seed dispersal effectiveness approaches

description: 1.While large avian frugivores are known to be key dispersers for
 large‐seeded tree species, their role in community‐wide plant‐disperser
 networks is still poorly known. Large avian frugivores are also among the
 most threatened due to anthropogenic impacts. 2.We evaluated the role of
 large avian frugivores in a plant‐disperser community by a) determining
 whether the plant‐disperser community was modular, with a distinct
 community of large frugivores (thereby highlighting their importance), b)
 determining relative qualitative and quantitative roles played by
 large‐bodied frugivores vis‐à‐vis other frugivores and c) determining
 impacts of large‐bodied frugivore loss on the plant‐disperser community.
 3.The study was carried at a tropical forest site in north‐east India
 which is part of the Eastern Himalaya Biodiversity Hotspot. We collected
 tree watch data (2055 h) from 46 tree species, which represented 85% of
 tree species that are predominantly bird‐dispersed in the area. 4.We found
 that the plant‐disperser community was modular, with a distinct module of
 large‐seeded tree species and large frugivores. Intermediate‐sized
 frugivores such as barbets and bulbuls were the most connected, while
 large‐sized frugivores, such as hornbills and imperial‐pigeons were
 moderately well‐connected. Qualitative and quantitative roles played by
 different dispersers varied across the gradient of frugivore body size.
 Hornbills, the largest avian frugivores, consumed a significantly greater
 number of fruits and swallowed larger proportions of fruits compared to
 other avian groups. In comparison to similar‐sized frugivores,
 imperial‐pigeons fed on larger‐sized fruits, highlighting their importance
 for dispersal of large‐seeded plants. Under simulated extinction
 scenarios, larger extinction cascades weren't necessarily caused by
 larger frugivores, however, extinctions of certain large‐bodied frugivores
 (hornbills, imperial‐pigeons) caused extinction cascades. 5.Integrating
 information from networks and seed dispersal effectiveness approaches
 enabled a better understanding of large frugivore role in a
 plant‐disperser community. While large‐bodied frugivores may not be
 playing a central role in plant‐disperser communities, they are crucial as
 seed dispersal service providers for large‐seeded plants. In conjunction
 with the reported local extinctions of large frugivores like hornbills
 from the south Asian region, this study's findings highlight the
 irreplaceable quantitative and qualitative impacts that tropical plant
 communities are likely to experience in the future.
description: RScript_JAE_Naniwadekar_etalThe R script that was used for data analysisJAE_Naniwadekar_etal_species_codesContains details of codes assigned to different plant and frugivore species across the different data filesdat_species_accum_samplescontains data that was used to plot frugivore species accumulation curvesdat_pakke_weight_network_bird_dispcontains visitation rate data of different frugivore species on different tree species that was used to construct the plant-disperser networkdat_gw_fw_finalcontains data of gape width of different frugivore species and the average diameter (width) of fruit species eaten by themdat_correl_species_level_gwcontains data of gape width of different frugivore species and degree, species strength, betweenness centrality and closeness centrality measures for each of the different species as extracted from each of the different frugivore speciesdat_fruit_removalcontains data for the generalized linear mixed effect models with negative binomial error structure to evaluate the number of fruits swallowed per visit as a function of the gape width of the frugivoredat_fruit_visit_ratecontains data for the linear mixed effect models to evaluate the visitation rate of the different frugivore species as a function of the gape width (body size) of the frugivoredata for seed dispersal effectiveness landscapecontains data for constructing the seed dispersal effectiveness landscapem1.csvdat_prop_fruit_swallow_fruit_widthcontains data to correlate the proportion of fruits swallowed as a function of fruit widthdat_anova_modulescontains data to compare gape width and degree of the different frugivore species that belong to different modules (A-E). Modules were determined using modularity analysis)dat_anova_modules_plantcontains data to compare fruit diameter and degree of the differen plant species that belong to different modules (A-E). Modules were determined using modularity analysisdat_chi_test_seed_size_modulescontains data to compare the relative proportion of small-, medium- and large-seeded tree species across the different modulesdat_extinct_scmmatrix that contains data on visitation rates of different frugivore species (in rows) on the different tree species (in columnsdat_extinct_order_extinctioncontains data on gape width, body length weight of the frugivores and proportion of fruits in the diet of each of the frugivore species as obtained from Wilman et al. (2015) that is useful for the stochastic co-extinction modelsdat_vector_rplantscontains data on the dependence of each plant species on animals for seed dispersal. Since all are animal-dispersed plant species, they all take a value of 1