TY - JOUR
T1 - Importance of weak trophic interactions in the structure of the food web in la Paz Bay, southern Gulf of California
T2 - A topological approach
AU - Navia, Andrés F.
AU - MacIel-Zapata, Sergio R.
AU - González-Acosta, Adrián F.
AU - Leaf, Robert T.
AU - Cruz-Escalona, Víctor H.
N1 - Publisher Copyright:
© 2019 Rosenstiel School of Marine and Atmospheric Science. All rights reserved.
PY - 2019/4
Y1 - 2019/4
N2 - Here, we describe the trophic structure of the La Paz Bay, Baja California Sur, Mexico, and evaluate the role of weak trophic interactions in the ecosystem using a suite of topological indices. We used information derived from published and unpublished stomach contents analysis studies from the region to construct an unweighted and directional trophic network (comprising 250 nodes and 1528 associated interactions) to assess the impact of predators in three scenarios. Each scenario simulated the removal of weak interactions corresponding to removal of those nodes with trophic contributions less than 5%, 10%, and 15%. In each removal scenario, the nodes phytoplankton and zooplankton exhibited the greatest betweenness and closeness centrality, suggesting that they are critical groups in the structure of the web, especially in the transference of indirect effects to the largest number of possible nodes in the network. The multiphyletic nature of the phytoplankton and zooplankton, and their ubiquity in diets served to increase their connectivity to all taxonomic groups. We note the presence of numerous weak interactions (67% of taxa have weak trophic interactions) and speculate that this characteristic confers ecological resilience in the Bay of La Paz coastal marine ecosystem.
AB - Here, we describe the trophic structure of the La Paz Bay, Baja California Sur, Mexico, and evaluate the role of weak trophic interactions in the ecosystem using a suite of topological indices. We used information derived from published and unpublished stomach contents analysis studies from the region to construct an unweighted and directional trophic network (comprising 250 nodes and 1528 associated interactions) to assess the impact of predators in three scenarios. Each scenario simulated the removal of weak interactions corresponding to removal of those nodes with trophic contributions less than 5%, 10%, and 15%. In each removal scenario, the nodes phytoplankton and zooplankton exhibited the greatest betweenness and closeness centrality, suggesting that they are critical groups in the structure of the web, especially in the transference of indirect effects to the largest number of possible nodes in the network. The multiphyletic nature of the phytoplankton and zooplankton, and their ubiquity in diets served to increase their connectivity to all taxonomic groups. We note the presence of numerous weak interactions (67% of taxa have weak trophic interactions) and speculate that this characteristic confers ecological resilience in the Bay of La Paz coastal marine ecosystem.
UR - http://www.scopus.com/inward/record.url?scp=85064811977&partnerID=8YFLogxK
U2 - 10.5343/bms.2018.0043
DO - 10.5343/bms.2018.0043
M3 - Artículo
AN - SCOPUS:85064811977
SN - 0007-4977
VL - 95
SP - 199
EP - 215
JO - Bulletin of Marine Science
JF - Bulletin of Marine Science
IS - 2
ER -