Spatio-Temporal Variations in Macroinvertebrate Assemblages of New Caledonian Streams.

Abstract

Forty-one sites located on 14 New Caledonian streams were surveyed four times between October 1996 and October 1997 in order to examine the spatial and temporal changes in the structure of the benthic macroinvertebrate communities. About 250 000 invertebrates representing 167 taxa were collected in the streams. Seventy-five percent of identified taxa and 67% of individuals were insects. Major spatial and temporal changes in the composition of the fauna were detected by multivariate analyses (ordination and classification). Overall, the number of individuals was significantly higher in the dry season (October) than in the wetter seasons (January and June). However, a low temporal variability was detected in the structure of benthic communities during the sampling period. A cluster analysis based on taxonomic composition separated five groups of sites in relation with rock type, land use, and geographic characteristics. Several metrics (total invertebrate density, taxon richness, relative abundance of major invertebrate groups, diversity indices) were used to characterize each group of sites. Forested streams, where the highest specific diversity occurred, represented the most speciose habitat for benthic fauna. A less rich and abundant fauna occurred in streams draining ultramafic rocks probably because of their low content in food resources and organic matter. Key-words : benthic macroinvertebrates, New Caledonia, tropical streams, biodiversity, spatial and temporal variability. VARIABILITÉ SPATIO-TEMPORELLE DE LA STRUCTURE DES COMMUNAUTÉS DE MACROINVERTÉBRÉS BENTHIQUES DANS LES RIVIÈRES DE LA NOUVELLE-CALÉDONIE. RÉSUMÉQuarante et une stations situées sur 14 cours d'eau répartis sur l'ensemble de la Nouvelle-Calédonie furent périodiquement échantillonnées entre octobre 1996 et octobre 1997. Des analyses multivariées (ordination et classification) permirent d'étudier la variabilité spatio-temporelle de la structure des communautés benthiques. Environ 250 000 invertébrés représentant 167 taxons furent prélevés durant l'étude. Soixante quinze pour cent des taxons identifiés et 67 % des individus prélevés furent des insectes.

Unique and shared effects of local and catchment predictors over distribution of hyporheic organisms: does the valley rule the stream?

“…Our extensive sampling of the hyporheic zone on New Caledonian streams and model predictions considerably enlarged the distribution range of bogidiellids and anthurids, which had so far been reported from a handful of localities (Mary andMarmonier 2000, Jaume et al 2007). Yet, bogidiellids and anthurids are essentially restricted to streams draining peridotite catchments.…”

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“…New Caledonian Odonata have been considered in several other investigations, which can be grouped as follows: a) species checklists for French overseas departments and territories (Dommanget 2000;Dommanget & Mashaal 2000Meurgey 2004;Grand 2006); b) taxonomic and phylogenetic studies (Kalkman et al 2010a, b;Kalkman & Theischinger 2013;Dijkstra et al 2014), c) general overviews for conservation purposes (Rowe 2004;Grand 2005); d) museum and private collections (Voisin 2001;Papazian 2002); e) hydrobiological studies (Mary 1999(Mary , 2002(Mary , 2017Pöllabauer et al 2005); f) studies on invertebrates that include Odonata (Bigot 1985;Jourdan & Mille 2006); g) studies over larger regions that encompass New Caledonia (Lieftinck 1959;Starmühlner 1986); h) general species distribution (Endersby 2002), and i) a bibliography checklist (Chazeau 1995). However, some of these publications should be treated with caution considering their use of nomenclature and the unknown accuracy of their identifications.…”

Review of New Caledonian species of Oxyethira Eaton, with description of 17 new species, and new records for Hydroptila Dalman and Hellyethira Neboiss (Trichoptera, Hydroptilidae)

“…Representatives of the genus found in New Caledonia appear to be no exception. This is apparent upon consideration of the variability among 26 species recorded here, and the similarity of the considerable number of unassociated final instar larvae collected at many sites by Mary (2002) in her survey of macroinvertebrates of the island’s streams.…”