A comparison of the density and diversity of intertidal benthic molluscs at a sheltered and an exposed tropical coast around Mauritius Island

  • Deepeeka Kaullysing Department of Marine & Ocean Science, Fisheries and Mariculture, Faculty of Ocean Studies, University of Mauritius, Réduit 80837, Republic of Mauritius
  • Nawsheen Taleb-Hossenkhan Department of Biosciences, Faculty of Science, University of Mauritius, Réduit 80837, Republic of Mauritius
  • Balasaheb Govind Kulkarni The Institute of Science, Government of Maharashtra, Mumbai 400032, India
  • Ranjeet Bhagooli Department of Marine & Ocean Science, Fisheries and Mariculture, Faculty of Ocean Studies, University of Mauritius, Réduit 80837, Republic of Mauritius
Keywords: sheltered, exposed, macrobenthic molluscs, species density, species diversity, grain size

Abstract

This study compared spatial variations in the density and diversity of marine benthic molluscs along Belle Mare and Gris Gris, a sheltered and an exposed intertidal zone, respectively, in Mauritius. Species density was assessed using the random quadrat method (1 m x 1 m). Grain size distribution was measured by sieve analysis. Shannon-Wiener (H’), evenness (E) and Simpson’s (D) indices were used to assess diversity. Coarser sediment was found at Gris Gris indicating the prevalence of relatively harsher wave conditions as compared to Belle Mare. Sixteen mollusc species were identi ed at Belle Mare (12 on rocky and 4 on sandy substrata) and seven species at Gris Gris (6 species on rocky and 1 on sandy substrata), with the families Planaxidae, Cerithiidae and Neritidae being common to both sites. Shannon-Wiener and evenness indices were higher at Gris Gris. Simpson’s index indicated higher dominance at Belle Mare, evident from the high density of Planaxis sulcatus (514.42 ± 221.63 individuals m-2) (mean ± SE). Turbo setosus was found in highest density (1.20 ± 0.20 individuals m-2) at Gris Gris. Though Belle Mare has higher intertidal mollusc abundance, the diversity was lower due to high dominance of species. This observation possibly signi es suitable physical conditions for species growth and survival at Belle Mare. 

Author Biographies

Deepeeka Kaullysing, Department of Marine & Ocean Science, Fisheries and Mariculture, Faculty of Ocean Studies, University of Mauritius, Réduit 80837, Republic of Mauritius

Department of Marine and Ocean Science, Fisheries and Mariculture

Lecturer

Nawsheen Taleb-Hossenkhan, Department of Biosciences, Faculty of Science, University of Mauritius, Réduit 80837, Republic of Mauritius

Department of Biosciences, Faculty of Science

Senior Lecturer

Balasaheb Govind Kulkarni, The Institute of Science, Government of Maharashtra, Mumbai 400032, India

The Institute of Science, Government of Maharashtra, Mumbai 400032, India

Professor

Ranjeet Bhagooli, Department of Marine & Ocean Science, Fisheries and Mariculture, Faculty of Ocean Studies, University of Mauritius, Réduit 80837, Republic of Mauritius

Department of Marine & Ocean Science, Fisheries and Mariculture

Associate Professor

Published
2017-08-14
Section
Articles

Journal Identifiers


eISSN: 0856-860X
print ISSN: 0856-860X