title: Diversity is maintained by seasonal variation in species abundance.
abstract: BACKGROUND
  Some of the most marked temporal fluctuations in species abundances are linked to seasons. In theory, multispecies assemblages can persist if species use shared resources at different times, thereby minimizing interspecific competition. However, there is scant empirical evidence supporting these predictions and, to the best of our knowledge, seasonal variation has never been explored in the context of fluctuation-mediated coexistence.
  
  
  RESULTS
  Using an exceptionally well-documented estuarine fish assemblage, sampled monthly for over 30 years, we show that temporal shifts in species abundances underpin species coexistence. Species fall into distinct seasonal groups, within which spatial resource use is more heterogeneous than would be expected by chance at those times when competition for food is most intense. We also detect seasonal variation in the richness and evenness of the community, again linked to shifts in resource availability.
  
  
  CONCLUSIONS
  These results reveal that spatiotemporal shifts in community composition minimize competitive interactions and help stabilize total abundance.
authors.affiliation: Centre for Biological Diversity and Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 9TH, UK. maadd@st-andrews.ac.uk.
authors.forename: Hideyasu
authors.initials: H
authors.lastname: Shimadzu
authors.forename: Maria
authors.initials: M
authors.lastname: Dornelas
authors.forename: Peter A
authors.initials: PA
authors.lastname: Henderson
authors.forename: Anne E
authors.initials: AE
authors.lastname: Magurran
mesh_terms: D000818:Animals; D044822:Biodiversity; D017753:Ecosystem; D005399:Fishes; D008962:Models, Theoretical; D011157:Population Dynamics; D012621:Seasons; D013045:Species Specificity