DOI: 10.5061/dryad.kd51c5bhq
title: Data from: Abundant top predators increase species interaction network complexity in Northeastern Chinese forests

description: Species interactions remain a cornerstone in shaping community dynamics
 and structure, alongside other factors such as climate conditions and
 human activities. Although network structure is known to influence
 community stability and ecosystem functioning, the roles of top predators
 in shaping interaction network structure remain obscure. We
 examined a 5-7 year time series of species detections for mammal
 communities in multiple protected areas to investigate the association
 between top predators and interaction network structure. Our
 findings suggest that abundant species, day-active species and species
 with wide habitat breadth interact with more species, as did species that
 were more affected byvehicle disturbance. With increased densities of top
 predators, interaction networks exhibited greater complexity, with
 increased connectance, nestedness, and average degree. An increased
 density of mesopredators, such as yellow-throated martens andbadgers, was
 associated with sparser, less nested, but more centralized interaction
 networks. Top predators reduced the degree of highly interactive species,
 making them more specialized, and increased the degree of less abundant
 species, making them more generalist. In particular, this redistribution
 of interactions was not driven by direct changes in species density of top
 predators but seemingly by nonconsumptive or indirect
 effects. Our findings emphasize the pivotal role of the main
 predators in structuring interactions within Northeastern China mammal
 communities, with large implications for conservation and management.
description: # Data from: Abundant top predators increase species interaction network
 complexity in Northeastern Chinese forests
 [https://doi.org/10.5061/dryad.kd51c5bhq](https://doi.org/10.5061/dryad.kd51c5bhq) ## Description of the data and file structure This dataset contains the input data which was used to explore ecological interactions and network parameters, model fitting code and the random interaction networks with 16-18 species. The dataset and model fitting code are available on **Zotero**. ### Files and variables #### File: ran\_net\_attr\_18.csv **Description:**  No unit (network attribute value) ##### Variables * Network_ID: A unique identifier for each network. * connectance: The connectance of the network, representing the fraction of possible connections that are actually realized. * nestness: A measure of how nested the network is, indicating the degree to which species with fewer interactions are connected to those with more interactions. * modularity: A measure of the modularity of the network, indicating how well the network can be divided into separate modules or communities * average.degree: The average number of connections per node (species) in the network. * centralization.betweenness: Measures how many “key species” exist in the network, where “key” is defined as species having a disproportionate number of interactions within a network (Vasas & Jordán, 2006). A higher value indicates a greater concentration of critical intermediary species that significantly influence network connectivity. * centralization.degree: The centralization of the network based on betweenness centrality, which measures the degree to which a species serves as a bridge in the network. #### File: ran\_net\_attr\_17.csv **Description:** No unit (network attribute value) ##### Variables * Network_ID: A unique identifier for each network. * connectance: The connectance of the network, representing the fraction of possible connections that are actually realized. * nestness: A measure of how nested the network is, indicating the degree to which species with fewer interactions are connected to those with more interactions. * modularity: A measure of the modularity of the network, indicating how well the network can be divided into separate modules or communities * average.degree: The average number of connections per node (species) in the network. * centralization.betweenness: Measures how many “key species” exist in the network, where “key” is defined as species having a disproportionate number of interactions within a network (Vasas & Jordán, 2006). A higher value indicates a greater concentration of critical intermediary species that significantly influence network connectivity. * centralization.degree: The centralization of the network based on betweenness centrality, which measures the degree to which a species serves as a bridge in the network. #### File: ran\_net\_attr\_16.csv **Description:** No unit (network attribute value) ##### Variables * Network_ID: A unique identifier for each network. * connectance: The connectance of the network, representing the fraction of possible connections that are actually realized. * nestness: A measure of how nested the network is, indicating the degree to which species with fewer interactions are connected to those with more interactions. * modularity: A measure of the modularity of the network, indicating how well the network can be divided into separate modules or communities * average.degree: The average number of connections per node (species) in the network. * centralization.betweenness: Measures how many “key species” exist in the network, where “key” is defined as species having a disproportionate number of interactions within a network (Vasas & Jordán, 2006). A higher value indicates a greater concentration of critical intermediary species that significantly influence network connectivity. * centralization.degree: The centralization of the network based on betweenness centrality, which measures the degree to which a species serves as a bridge in the network. #### File: CauNetPros.xlsx  "Species" Sheet ##### Variables * **area**: Name of the area where the species data was collected. - **num**: An identification number for the species record. * **species**: The common name of the species. * **degree**: The degree value of the species in the ecological network. * **degree_prop**: Proportional degree of the species.  * **Pedestrian - Livestock**: If this species was impacted by pedestrian, vehicle or livestock.  * **density**: The estemated population density of the species. * **body_mass_g -** **foraging_stratum**:  Species traits. - **ForestType**: The forest type ( top predator abundant forests, TAF, or top predator less abundant forests, TLF)  "Community" Sheet * **area**: Name of the area where the species data was collected.  * **num.edges:** The number of edges in the ecological network.  * **num.vertices:** The number of vertices in the ecological network.  - **connectance - centralization.degree:** The attibutes of networks. No unit (network attribute value). - **ForestType**: The forest type ( top predator abundant forests, TAF, or top predator less abundant forests, TLF). - **NPP:** Annual mean net primary production. - **Pre:** Annual mean precipitation. - **Tem:**  Annual mean temperature. - **SSMBA:** The size of the spatial monitoring buffer area allocated for camera trap arrays within each study site. - **Tiger -  Rat:** The estemated population density of the species. * **Pedestrian - Livestock:** The unit number of occurrences of pedestrian, vehicle or livestock. Variable Units: * all network attribute: No unit. * density: kg/km² * body_mass_g: g * longevity_y: year * gestation_length_d: day - litter_size_n: n - litters_per_year_n: n/year - generation_length_d: day * dispersal_km: km - home_range_km2: km² - diet_breadth_n: n - Tiger -  Rat in "Community" Sheet:  density; kg/km² - NPP: kgC/m²/year - Pre: mm - Tem:  ℃ - SSMBA: km² #### File: CauNetPros.xlsx This Rscript_sequ.R script performs several data analysis and visualization tasks，including **Data Loading and Cleaning**, **Linear Mixed Effects Models (LMM, Regression Diagnostics**, **Shapiro-Wilk Normality Test**, **Linear Regression**, **Permutational Test**, **Randomized Network Analysis**, **Result Export** ## Access information Other publicly accessible locations of the data: * [https://doi.org/10.5281/zenodo.14198394](https://doi.org/10.5281/zenodo.14198394)