Influence of hard bottom morphology on fish assemblages of the continental shelf off Georgia, southeastern USA

Various reef types worldwide have inconsistent relationships among fish assemblage parameters and benthic characteristics, thus there is a need to identify factors driving assemblage structure specific to each reef type and locale. Limestone ledges are known to be key habitats for bottom fish on the continental shelf of the southeastern USA, however, the specific factors that link them to fish assemblages have not been quantified. Bottom fishes and habitat characteristics on ledges were surveyed at a study site located centrally in the southeastern USA continental shelf. Species richness, diversity, abundance, and biomass of fish were higher at ledges than on flat bottom. Species richness, abundance, and biomass of fish were well explained by ledge variables including percent cover of sessile invertebrates, total height, and height of undercut recesses. Multivariate analyses based on biomass of individual species at ledges revealed two fish assemblages associated with four ledge types. One assemblage was associated with ledges that were tall, heavily colonized with sessile invertebrates, large in area, and did or did not have undercuts. The other assemblage was associated with ledges that were short, not undercut, smaller in area, and were or were not heavily colonized by invertebrates. Seafloor classification schemes presently used in the region do not adequately capture hard bottom diversity to identify the location and extent of essential fish habitats for ecological and fisheries purposes. Given that ledges cover only ∼1% to 5% of the southeastern USA continental shelf, they merit the highest levels of consideration in regional research, conservation, and management plans.

Study of disparate sectors in fisheries

Fisheries employ a number of people and fisheries industry is truly an amalgamation of various disparate sectors. Fisheries play an important role in Indian economy and it provides employment to a number of people. For planning of integrated development of fisheries industry and resource management, a considerable amount of information is required. In this paper a study of the disparate sectors with regards to the nature of work, number of workers, sex-wise participation, earning type and earning in Indian Rupees in the year 1991-92, 1992-93, 1993-94 and 1999-2000 has been done in a selected fishing village. The geographical locale where the study has been done is Versova fishing village which is a major fish landing centre in Mumbai. The study has revealed that there are a number of disparate sectors in fisheries and in this fishing village on an average, a boat owner provided employment to 30-60 people in the year 1994 and to 19-25 people in 1999. Though this number has shown a decreasing trend with the advancement of years, it is however, seen that a number of people are employed in various disparate sectors in fisheries. It is necessary to highlight this and in any developmental planning, all these sectors should be given equal importance.