title: Community Structure of Tintinnid Ciliates of the Microzooplankton in the South West Pacific Ocean: Comparison of a High Primary Productivity with a Typical Oligotrophic Site.
abstract: Transient 'hot spots' of phytoplankton productivity occur in the generally oligotrophic Southern Pacific Ocean and we hypothesized that the population structure of tintinnid ciliates, planktonic grazers, would differ from that of a typical oligotrophic sites. Samples were collected over a 1-wk period at each of two sites between Fiji and Tahiti: one of elevated chlorophyll a concentrations and primary productivity with an abundance of N-fixing cyanobacteria Trichodesmium, and a distant oligotrophic site. Tintinnid abundance differed between the sites by a factor of 2. A single species (Favella sp.), absent from the oligotrophic site, highly dominated the 'hot spot' site. However, total species richness was identical (71 spp.) as well as short-term temporal variability (2-4 d). At both sites, species abundance distributions most closely fit a log-series or log-normal distribution and the abundance distributions of ecological types, forms of distinct lorica oral diameter, were the typical geometric. Morphological diversity was only slightly lower at the high productivity site. We found that communities of these plankton grazers in 'hot spots' of phytoplankton productivity in oligotrophic systems, although harboring different species, differ little from surrounding oligotrophic areas in community structure.
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 7093, Laboratoire d'Océanographie de Villefranche de Villefranche-sur-Mer (LOV), Villefranche-sur-Mer, 06230, France. dolan@obs-vlfr.fr.
authors.forename: John R
authors.initials: JR
authors.lastname: Dolan
authors.affiliation: MIO (Institut Méditerranéen d'Océanologie), Campus de Luminy, Marseille Cedex 9, 13288, France.
authors.forename: Audrey
authors.initials: A
authors.lastname: Gimenez
authors.affiliation: MIO (Institut Méditerranéen d'Océanologie), Campus de Luminy, Marseille Cedex 9, 13288, France.
authors.forename: Veronique
authors.initials: V
authors.lastname: Cornet-Barthaux
authors.affiliation: MIO (Institut Méditerranéen d'Océanologie), Campus de Luminy, Marseille Cedex 9, 13288, France.
authors.forename: Alain
authors.initials: A
authors.lastname: de Verneil
mesh_terms: D000818:Animals; D044822:Biodiversity; D002734:Chlorophyll / Q000378:metabolism; D000077194:Chlorophyll A; D016798:Ciliophora / Q000502:physiology*; D000458:Cyanobacteria / Q000378:metabolism; D005367:Fiji; D010140:Pacific Ocean; D010839:Phytoplankton / Q000378:metabolism; D011114:Polynesia; D012623:Seawater / Q000737:chemistry; D015048:Zooplankton / Q000502:physiology*
chemical_list: D002734:Chlorophyll; D000077194:Chlorophyll A
keywords: 
  Trichodesmium
  ; Biodiversity; biogeography; choreotrichia; plankton; species abundance distribution