Coral reef fish abundance and diversity of seagrass beds in Kavaratti atoll, Lakshadweep, India

Abstract

The community organization of coral reef fishes in the seagrass sub-habitat of
Kavaratti toll, Lakshadweep, India was studied during the period from January
1991 to June 1992. Twenty-seven families represented by 65 species were
recorded by the visual censes method. The community diversity for families and
species was 2.49 and 3.14 respectively. Juveniles and sub-adults of the most
adult reef fish, which inhabit other sub-habitats, were recorded here. The high
species diversity in the seagrass beds is due to their roles as nurseries, shelter
and foraging grounds for many species. Labridae, Chaetodontidae, Acanthuridae
and Mullidae were the most speciose families. Ocurrence of siganids was highly
seasonal. The cover that seagrass canopy provides conceals many species and
perhaps influenced counts. The occurrence of balistids could be related to the
presence of interstitial and patches and abundant invertebrate food. Scorpaenids
subsisted on abundant invertebrates and juveniles fishes. High counts and
pronounced variations make seagrass beds unstable habitats. However, monsoon
assemblages were relatively stable perhaps due to lack of excessive new recruits
and a habitat shift by most species.