DOI: 10.5061/dryad.15dv41nvv
title: Data from: Seasonal dynamics of flock interaction networks across a human-modified landscape in lowland Amazonian rainforest

description: Although lowland tropical rainforests were once widely believed to be the
 archetype of stability, seasonal variation exists. In these environments,
 seasonality is defined by rainfall, leading to a predictable pattern of
 biotic and abiotic changes. Only the full annual cycle reveals niche
 breadth, yet most studies of tropical organisms ignore seasonality,
 thereby underestimating realized conditions. If human-modified habitats
 display more seasonal stress than intact habitats, then ignoring
 seasonality will have particularly important repercussions for
 conservation. We examined the seasonal dynamics of Amazonian mixed-species
 flocks—an important species interaction network—across three habitats with
 increasing human disturbance. We quantified seasonal space use, species
 richness and attendance, and four ecological network metrics for flocks in
 primary forest, small forest fragments, and regenerating secondary forest
 in central Amazonia. Our results indicate that, even in intact, lowland
 rainforest, mixed-species flocks exhibit seasonal differences. During the
 dry season, flocks included more species, generally ranged over larger
 areas, and displayed network structures that were less complex and less
 cohesive. We speculate that because most flocking species nest during the
 dry season—a time of reduced arthropod abundance—flocks are simultaneously
 constrained by these two competing pressures. Moreover, these seasonal
 differences were most pronounced in forest fragments and secondary forest,
 habitats that are less buffered from the changing seasons. Our results
 suggest that seasonality influences the conservation value of
 human-modified habitats, raising important questions about how rainforest
 organisms will cope with an increasingly unstable climate.
description: Species composition data were collected as described in this
 paper and Rutt et al. (2020): CLR followed flocks on foot and recorded
 species composition in 30-min time blocks. We curated the list of
 "flocking species" to exclude bycatch, which we considered to be
 any species other than the 105 that we listed in the appendices of these
 two papers (Appendix S1: Table S1 of this study and the Appendix of the
 Biological Conservation paper). Rutt, C.L., Mokross,
 K., Kaller, M.D., and P.C. Stouffer. 2020. Experimental forest
 fragmentation alters Amazonian mixed-species flocks. Biological
 Conservation 242: 108415.
description: The 8 columns of the species composition data
 (Amazonian_flock_species_compositions_EcolAppl2020.csv) should all be
 fairly intuitive, except for species codes, for which we've deposited
 a separate key (Species_code_key.docx): flock -- We
 have 12 flocks in this study, each with a unique name and a four-digit
 reserve code date_cal -- This is simply the
 date time -- CLR originally recorded species
 composition in 10-min timebands, which were later aggregated into 30-min
 timeblocks (timeblock) vegetation -- We followed flocks
 in three treatments: primary forest (prim_forest), secondary forest
 (sec_forest), and ~10-ha fragments (10_ha) network --
 Each flock will contain two networks, one for the dry season and another
 for the wet season (flock_dry and flock_wet)