Weighted interaction networks and plant traits
Weighted plant-bird interaction networks at two sites in the Manú Biosphere Reserve in the Andes of south-east Peru. At each site, we installed plots of 100 m x 30 m (six plots in Wayqecha, eight plots in San Pedro) and sampled networks four times approximately every three months between December 2009 and September 2010. In each round, we observed each transect for 30 h on five consecutive days and recorded which bird species fed on which plant species (total observation time 720 h in Wayqecha and 960 h in San Pedro). For all plants species we collected the following morphological traits: fruit length and diameter (mm), crop mass (g, fruit mass * number of fruits per plant), and plant height (m). Plant traits were sampled in the field.