title: Key features of intertidal food webs that support migratory shorebirds.
abstract: The migratory shorebirds of the East Atlantic flyway land in huge numbers during a migratory stopover or wintering on the French Atlantic coast. The Brouage bare mudflat (Marennes-Oléron Bay, NE Atlantic) is one of the major stopover sites in France. The particular structure and function of a food web affects the efficiency of carbon transfer. The structure and functioning of the Brouage food web is crucial for the conservation of species landing within this area because it provides sufficient food, which allows shorebirds to reach the north of Europe where they nest. The aim of this study was to describe and understand which food web characteristics support nutritional needs of birds. Two food-web models were constructed, based on in situ measurements that were made in February 2008 (the presence of birds) and July 2008 (absence of birds). To complete the models, allometric relationships and additional data from the literature were used. The missing flow values of the food web models were estimated by Monte Carlo Markov Chain--Linear Inverse Modelling. The flow solutions obtained were used to calculate the ecological network analysis indices, which estimate the emergent properties of the functioning of a food-web. The total activities of the Brouage ecosystem in February and July are significantly different. The specialisation of the trophic links within the ecosystem does not appear to differ between the two models. In spite of a large export of carbon from the primary producer and detritus in winter, the higher recycling leads to a similar retention of carbon for the two seasons. It can be concluded that in February, the higher activity of the ecosystem coupled with a higher cycling and a mean internal organization, ensure the sufficient feeding of the migratory shorebirds.
authors.affiliation: Université de la Rochelle-CNRS, UMR 7266, Littoral Environnement et Sociétés (LIENSs), La Rochelle, France.
authors.forename: Blanche
authors.initials: B
authors.lastname: Saint-Béat
authors.forename: Christine
authors.initials: C
authors.lastname: Dupuy
authors.forename: Pierrick
authors.initials: P
authors.lastname: Bocher
authors.forename: Julien
authors.initials: J
authors.lastname: Chalumeau
authors.forename: Margot
authors.initials: M
authors.lastname: De Crignis
authors.forename: Camille
authors.initials: C
authors.lastname: Fontaine
authors.forename: Katell
authors.initials: K
authors.lastname: Guizien
authors.forename: Johann
authors.initials: J
authors.lastname: Lavaud
authors.forename: Sébastien
authors.initials: S
authors.lastname: Lefebvre
authors.forename: Hélène
authors.initials: H
authors.lastname: Montanié
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Mouget
authors.forename: Francis
authors.initials: F
authors.lastname: Orvain
authors.forename: Pierre-Yves
authors.initials: PY
authors.lastname: Pascal
authors.forename: Gwenaël
authors.initials: G
authors.lastname: Quaintenne
authors.forename: Gilles
authors.initials: G
authors.lastname: Radenac
authors.forename: Pierre
authors.initials: P
authors.lastname: Richard
authors.forename: Frédéric
authors.initials: F
authors.lastname: Robin
authors.forename: Alain F
authors.initials: AF
authors.lastname: Vézina
authors.forename: Nathalie
authors.initials: N
authors.lastname: Niquil
mesh_terms: D025041:Animal Migration / Q000502:physiology*; D000818:Animals; D001267:Atlantic Ocean; D001419:Bacteria / Q000254:growth & development; D061006:Bays; D001717:Birds / Q000502:physiology*; D017753:Ecosystem; D020387:Food Chain; D005602:France; D005843:Geography; D007448:Invertebrates / Q000254:growth & development; D008390:Markov Chains; D008954:Models, Biological; D009010:Monte Carlo Method; D012621:Seasons