, Volume 346, Issue 1–3, pp 137–148 | Cite as

Differences in composition of small, motile invertebrate assemblages from seagrass and unvegetated habitats in a southern Australian estuary

  • Rod M. Connolly


Assemblages of small, motile invertebrates (epifauna) from eelgrass(Zostera muelleri) and unvegetated habitats in a shallow, marine-dominatedestuary were compared at five sampling periods over one year. Assemblagesbased on abundance and biomass of 21 taxa from the two habitats groupedseparately in multivariate analyses (MDS ordination), and these groupingswere shown to be significant using an analysis of similarities (ANOSIM)randomisation routine. Secondarily to habitat differences, weak influencesof water temperature and distance to open water, but not of salinity, weredetected at some periods. Abundance and biomass of key taxa and all speciescombined were higha in eelgrass than in unvegetated habitat. Cumaceans wereexceptional in being collected predominantly from unvegetated habitat. Totalepifaunal production and crustacean production estimated using twovariables, (1) the biomass of individuals of each size class, and (2) watertemperature, were also higher in eelgrass than in unvegetated habitat. Thehigher abundance in eelgrass of taxa such as amphipods, harpacticoidcopepods and polychaetes that are major components of the diets of smallfish is consistent with a model explaining higher fish numbers in eelgrassin terms of prey availability.

epifauna seagrass community composition ANOSIM Crustacea Zostera 


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Copyright information

© Kluwer Academic Publishers 1997

Authors and Affiliations

  • Rod M. Connolly
    • 1
  1. 1.Department of ZoologyUniversity of AdelaideSouth AustraliaAustralia

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