DOI: 10.5061/dryad.1mv20r6
title: Data from: Feeding environment and other traits shape species' roles in marine food webs

description: Food webs and meso-scale motifs allow us to understand the structure of
 ecological communities and define species' roles within them. This
 species-level perspective on networks permits tests for relationships
 between species' traits and their patterns of direct and indirect
 interactions. Such relationships could allow us to predict food-web
 structure based on more easily-obtained trait information. Here we
 calculated the roles of species (as vectors of motif position frequencies)
 in six well-resolved marine food webs and identified the motif positions
 associated with the greatest variation in species' roles. We then
 tested whether the frequencies of these positions varied with
 species' traits. Despite the coarse-grained traits we used, our
 approach identified several strong associations between traits and motifs.
 Feeding environment was a key trait in our models and may shape
 species' roles by affecting encounter probabilities. Incorporating
 environment into future food web models may improve predictions of an
 unknown network structure.
description: <strong>Please note: The .xls versions of the food webs
 initially uploaded are missing some columns. Please use the updated .csv
 versions of the food webs instead. </strong>
 <strong>Trait and role data file </strong>
 Species traits and frequencies of each motif position.
 Position columns are labelled R1 through R30, with position
 numbers as in Fig. 1 of the main text associated with this data.
 full_data.csv <strong>Kongsfjorden food
 web</strong> Food web for the Kongsfjord.
 Predator names are given in the first row, prey names in the first column.
 Values of 1 indicate a link. Data compiled by Ute Jacob (not previously
 published). kongsfjorden_spames.xls
 <strong>Lough Hyne food web </strong>
 Lough Hyne food web with genus names and ITIS ID numbers. Names
 and IDs for predators are given in the first two rows while names and IDs
 for prey are given in the first two columns. Values of 1 indicate feeding
 links. Data compiled by Ute Jacob (not previously published).
 loughhyne_spnames.xls <strong>Reef food
 web </strong> Food web for the Caribbean Reef.
 Predator names are given in the first row, prey names in the first column.
 Values of 1 indicate a feeding link. First published in: Opitz, S. 1996.
 Trophic interactions in Caribbean coral reefs. ICLARM Tech. Rep, 43, 341
 p. reef_spnames.xls
 <strong>St. Marks food web</strong>
 Food web for the St. Marks estuary, Florida, U.S.A. Predator
 names are given in the first row, prey names in the first column. Values
 of 1 indicate feeding links. First published in: Christian Luczkovich
 (1991), Organizing and understanding a winters seagrass foodweb network
 through effective trophic levels. Ecological Modelling (117): 99-124.
 doi:10.1016/S0304-3800(99)00022-8 stmarks_spnames.xls
 <strong>Weddell Sea food web </strong>
 Weddell Sea food web with predator names provided in the first
 row, prey names in the first column. First published in: Jacob et al.
 (2011), The Role of Body Size in Complex Food Webs: A Cold Case. In Andrea
 Belgrano and Julia Reiss, editors: Advances in Ecological Research, Vol.
 45, Amsterdam, The Netherlands, pp. 181-223.
 doi:10.1016/B978-0-12-386475-8.00005-8. weddell_spnames.xls
 <strong>Ythan estuary food web</strong>
 Food web for the Ythan Estuary with predator names given in the
 first row and prey names given in the first column. Values of 1 indicate
 feeding links. First published in: Cohen et al. (2009), Food webs are more
 than the sum of their tritrophic parts. PNAS (52): 22335-22340. doi:
 10.1073/pnas.0910582106 ythan_spnames.xls