Abrupt shifts in the Gironde fish community: an indicator of ecological changes in an estuarine ecosystem

Type Article
Date 2016-05
Language English
Author(s) Chevillot Xavier1, Pierre Maud1, Rigaud Arthur1, Drouineau Hilaire1, Chaalali Aurelie2, Sautour Benoit3, Lobry Jeremy1
Affiliation(s) 1 : Irstea, UR EABX, 50 Ave Verdun, F-33612 Cestas, France.
2 : IFREMER, Dept Ecol & Modeles Halieut, Rue Ile dYeu,BP 21105, F-44311 Nantes, France.
3 : Univ Bordeaux, Environm & Paleoenvironm Ocean & Continentaux, CNRS UMR EPOC 5805, Stn Marine Arcachon, 2 Rue Pr Jolyet, F-33120 Arcachon, France.
Source Marine Ecology Progress Series (0171-8630) (Inter-research), 2016-05 , Vol. 549 , P. 137-151
DOI 10.3354/meps11681
WOS© Times Cited 19
Keyword(s) Ecosystem state, Fish diversity, Estuary, Generalised linear mixed models, GLMM, Time series, Shift, Inter-shift periods
Abstract For decades, global climate change has directly and indirectly affected the structure and function of ecosystems. Abrupt changes in biodiversity have been observed in response to linear or sudden modifications to the environment. These abrupt shifts can cause long-term reorganizations within ecosystems, with communities exhibiting new functional responses to environmental factors. Over the last 3 decades, the Gironde estuary in southwest France has experienced 2 abrupt shifts in both the physical and chemical environments and the pelagic community. Rather than describing these shifts and their origins, we focused on the 3 inter-shift periods, describing the structure of the fish community and its relationship with the environment during these periods. We described fish biodiversity using a limited set of descriptors, taking into account both species composition and relative species abundances. Inter-shift ecosystem states were defined based on the relationship between this description and the hydro-physico-chemical variables and climatic indices defining the main features of the environment. This relationship was described using generalized linear mixed models on the entire time series and for each inter-shift period. Our results indicate that (1) the fish community structure has been significantly modified, (2) environmental drivers influencing fish diversity have changed during these 3 periods, and (3) the fish-environment relationships have been modified over time. From this, we conclude a regime shift has occurred in the Gironde estuary. We also highlight that anthropogenic influences have increased, which re-emphasizes the importance of local management in maintaining fish diversity and associated goods and services within the context of climate change.
Full Text
File Pages Size Access
Publisher's official version 15 1 MB Open access
Supplementary material 5 190 KB Open access
Top of the page

How to cite 

Chevillot Xavier, Pierre Maud, Rigaud Arthur, Drouineau Hilaire, Chaalali Aurelie, Sautour Benoit, Lobry Jeremy (2016). Abrupt shifts in the Gironde fish community: an indicator of ecological changes in an estuarine ecosystem. Marine Ecology Progress Series, 549, 137-151. Publisher's official version : https://doi.org/10.3354/meps11681 , Open Access version : https://archimer.ifremer.fr/doc/00334/44567/