Lekshmi2 and A. Patil3
Coastal Agricultural Research Institute, Old Goa-403 402, India
Institute of Fisheries Technology, Cochin-682 029, India
3DIVE GOA, Goa-403
Author Email :
Aim: The objective of
the study was to test the hypothesis that submerged shipwrecks along the
western coast of India can function as artificial fish habitats with trophic
structure of fish assemblages similar to natural rocky reef habitats.
Methodology: The fish
assemblages on shipwreck and natural reefs were analysed from September 2013
to December 2016 using diver assisted underwater visual census (UVC). Data
collected on fish assemblages were used to compare the fish trophic structure
between shipwreck and natural reefs using diversity indices, permutational
multivariate analysis of variance and similarity percentage analysis.
Results: Fish abundance
was two times greater on shipwreck than on natural reefs and the major
trophic guilds on shipwreck were omnivores and carnivores. Multivariate analyses
showed a distinct fish trophic structure on shipwreck from that of natural
reefs and certain fish species differentiated the trophic structure of
shipwreck from natural reefs. The high densities of Pomadasys furcatus, P.
guoraca, Pempheris multiradiata, Lutjanus indicus, L. fulvus, Ostorhinchus
compressus, Epinephelus coioides, E. erythrurus, Monodactylus argenteus
and Heniochus singularis contributed significantly to the average
dissimilarity for fish assemblages in shipwreck from natural reefs. This has
helped to differentiate the fish communities on shipwreck from natural reefs.
Interpretation: This study showed
that shipwreck and natural reefs differ significantly in fish trophic
structure. Fish species richness and abundance were significantly higher on
shipwreck than natural reefs. Therefore, the Greater species richness,
abundance and diversity of fish communities on shipwreck could be a result of
unique, complex and heterogeneous habitat features existing within the wreck.
Key words: Fish diversity, Grande Island, Habitat complexity,
Natural reef, Shipwreck