Current status and biodiversity modification in the coastal wetland ecosystems of India with objectives for its sustainable management

The South West (S.W.) coast of India is blessed with a series of wetland systems popularly referred to as backwaters covering a total area of 46128.94 ha. These backwaters are internationally renowned for their aesthetic and scientific values including being a repository for several species fish and shell fishes. This is more significant in that three wetlands (Vembanad, Sasthamcotta and Ashtamudi) have recently been designated as Ramsar sites of international importance. Thirty major backwaters forming the crux of the coastal wetlands form an abode for over 200 resident or migratory fish and shellfish species. The fishing activities in these water bodies provide the livelihood to about 200,000 fishers and also provide full-time employment to over 50,000 fishermen. This paper describes the changes on the environmental and biodiversity status of selected wetlands, during 1994-2005 period. The pH was generally near neutral to alkaline in range. The salinity values indicated mixohaline condition ranging from 5.20-32.38 ppt. in the 12 wetlands. The productivity values were generally low in most of the wetlands during the study, where the gross production varied from 0.22 gC/m3/day in Kadinamkulam to 1.10 gC/m3/day in the Kayamkulam. The diversity of plankton and benthos was more during the pre-monsoon compared to the monsoon and post-monsoon periods in most of the wetlands. The diversity of plankton and benthos was more during the pre-monsoon compared to the monsoon and post-monsoon periods in most of the wetlands. The average fish yield per ha. varied from 246 kg. in Valapattanam to 2747.3 kg. in Azhikode wetland. Retting of coconut husk in most of the wetlands led to acidic pH conditions with anoxia resulting in the production of high amounts of sulphide, coupled with high carbon dioxide values leading to drastic reduction in the incidence and abundance of plankton, benthic fauna and the fishery resources. The major fish species recorded from the investigation were Etroplus suratensis, E. maculatus, Channa marulius, Labeo dussumieri, Puntius sp. Lutianus argentimaculatus, Mystus sp., Tachysurus sp. and Hemiramphus sp. The majority of these backwaters are highly stressed, especially during the pre monsoon period when the retting activity is at its peak. The study has clearly reflected that a more restrained and cautious approach is needed to manage and preserve the unique backwater ecosystems of South-west India

Institutional Analysis of Marine Fisheries Management Practices in Kerala, India

The study is important for the fact that it places the management dynamics of marine fisheries sector in the context of growing unrest of local communities over the emerging resource conflicts and degradation Economic crisis in small scale marine fisheries due to high operating cost continue to hinder the efforts towards conservation in many ways The migration of mechanized fleet as a response to profit maximization strategy of enterprises continues to be a threat to resource management Therefore this study explores how to revamp the small scale mechanized sector effectively and profitably to ensure rational allocation of resources The thesis attempts to examine how livelihood vulnerabilities of artisanal fish workers influence the crafting of management institutions Finally by combining insights of an institutional framework the study establishes the need for recognising the role of both formal and informal institutions in the management of marine fisheries in Kerala

Genetic divergence in lobsters (Crustacea: Palinuridae and Scyllaridae) from the Indian EEZ

The management of exploited species requires the identification of demographically isolated populations that can be considered as independent management units (MUs), failuring in which can lead to over -fishing and depletion of less productive stocks. By characterizing the distribution of genetic variation, population sub structuring can be detected and the degree of connectivity among populations can be estimated. The genetic variation can be observed using identified molecular markers of both nuclear and mitochondrial origin. Hence, the present work was undertaken to study the genetic diversity and population/stock structure in P. homarus homarus and T. unimaculatus from different landing centres along the Indian coast using nuclear (RAPD) and mitochondrial DNA marker tools which will help towards developing management strategies for management and conservation of these declining resources.To make consistent conservation and fisheries management decisions, accurate species identifications are needed. It is also suggested that it is not always desirable to rely on a single sequence for taxonomic identification. Thus, the feasibility of using partial sequences of additional mitochondrial genes like 16SrRNA, 12SrRNA and nuclear 18SrRNA has also been explored in our study. Phylogenies provide a sound foundation for establishing taxonomy. The present work also attempts to reconstruct the phylogeny of eleven species of commercially important lobsters from the Indian EEZ using molecular markers