Socio-economic analysis of finfish culture in cages in coastal waters of Kerala, southwest coast of India

Cage culture of finfish is becoming a popular alternate source of livelihood in Vembanad Lake in Kerala, India. A study was conducted during November to December, 2016 to assess the socio-economic status of the farmers practicing cage culture in Kerala and the resultant economic benefits. Data on demographic features, farming activities, specific culture and farm management practices, economics and problems related to cage farming were collected from 36 active farmers of the Ernakulam District. Etroplus suratensis (Pearl spot), Lates calcarifer (Asian sea bass), and Genetically Improved Farm Tilapia (GIFT) were the major species culture

Good Environment Management of cage farming using a coupled 3D hydrodynamic particle tracking model - A case study from Pizhala, Cochin, India

Hydrographic conditions such as water level, velocity, adequate water circulation and stratifications have a strong influence on the management of fish cage culture in the estuarine environment. In this study, a 3D hydrodynamic model was used to identify the areas of the mixed and stratified water column and to use this in conjunction with particle tracking models for appropriate site selection for cage culture. A Lagrangian method was used to simulate the instantaneous release of "particles" emulating discharge from fish cages to show the behaviour of waste in terms of water circulation and water exchange. Model simulation at Pizhala cage farm revealed that desirable water exchange is experienced in the monsoon and pre-monsoon period. There have existed strong spring-neap variability in the water level with an average range of 0.7 m with a speed of < 0.12 m/s in pre-monsoon and < 0.24 m/s in monsoon. This consistent flow patterns in the Pizhala region helps in the replenishment of oxygenated water and removal of waste produced beneath the cages, and it is corroborated by the Lagrangian particle transport model experiment coupled with Finite Volume Community Ocean Model (FVCOM) in the study

Influence of selected anthropogenic impacts on ecology of Vembanad Lake

Influence of selected anthropogenic impacts on ecology of Vembanad Lak

Conservation of seagrass beds with special reference to associated species and fishery resources

The southeast coast of India bordering Gulf of Mannar and Palk Bay has luxuriant growth of seagrass beds which sustain good fisheries and is a biodiversity hotspot. Many fishers living along the coast depend on these resources for their livelihood. Several species of invertebrates and vertebrates fully depend on the seagrass resources for their survival and sustenance. In this paper, the diversity of species commonly associated with the seagrass beds and their present status is presented followed by the fisheries associated with this ecosystem. The type of fishing activities including the details of crafts, gears, number of fishers involved and catch statistics are presented. The main objective of this approach is to understand how the fishing activities influence the ecosystem and fishermen. Underwater monitoring and visual observations were documented through photographs and videos. Artisanal fishing activities such as bottom set gillnet, push net, lead-fish trap net and shore seine are in detail discussed and the conservation measures which are urgently required are also presented

Seasonal variability in the water quality, sediment characteristics and macrobenthic community structure in the vicinity of finfish cage culture sites in a tropical estuary along the south-west coast of India

Cage culture in estuaries and backwater systems is augmented as an additional source of income among the coastal population. However, the growing popularity of cage culture has resulted in its expansion to a greater level. Hence the present study was carried out to identify the impacts associated with cage culture on the water quality, sediment characteristics, macrobenthic abundance, and the community structure of the fishing island Pizhala on the southwest coast of India on a seasonal scale. The sample was taken from six stations near the cage (<1m) and two reference stations (200-300 m away). The study revealed significant variation in the water quality between the seasons. The DO concentration during pre-monsoon (PRM) had considerable variation between the cage sites and reference sites (RF). The sediment organic carbon in cage sites was consistently higher than the RF irrespective of the season. The RF sites had higher species diversity than the cage sites contributed mainly by sensitive organisms like amphipods. The feeding guild analysis revealed a higher abundance of sub-surface deposit feeders (SSDF) and surface deposit feeders in the cage sites corresponding to an increase in the sediment organic carbon concentration

Impact of a catastrophic flood on the heavy metal pollution status and the concurrent responses of the bentho-pelagic community in a tropical monsoonal estuary

Consequences of a catastrophic flood on the habitat quality and the concurrent responses of the bentho-pelagic community were studied in Cochin estuary, a eutrophic estuary along the southwest coast of India. The episodic flood in 2018 led to a marked decline in the dissolved nutrients and heavy metal concentrations in water and sediments of the estuary. The pre-flood phytoplankton abundance dominated by a bloom-forming species Cerataulina bicornis experienced a significant drop after the flood. Contrarily, zooplankton and macrobenthos responded favorably towards the flood-imposed habitat alterations. Higher susceptibility to heavy metal pollution and increased grazing pressure from gelatinous carnivores restricted the abundance of Copepoda, the dominant zooplankton taxon during pre-flood. The lower heavy metal concentration in the sediment after the flood favored higher macrobenthic abundance and diversity with a conspicuous change in the community structure from opportunistic polychaetes, indicators of pollution to molluscans and crustaceans, indicators of the healthy benthic zones

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Not AvailableThe southeast coast of India bordering Gulf of Mannar and Palk Bay has luxuriant growth of seagrass beds which sustain good fisheries and is a biodiversity hotspot. Many fishers living along the coast depend on these resources for their livelihood. Several species of invertebrates and vertebrates fully depend on the seagrass resources for their survival and sustenance. In this paper, the diversity of species commonly associated with the seagrass beds and their present status is presented followed by the fisheries associated with this ecosystem. The type of fishing activities including the details of crafts, gears, number of fishers involved and catch statistics are presented. The main objective of this approach is to understand how the fishing activities influence the ecosystem and fishermen. Underwater monitoring and visual observations were documented through photographs and videos. Artisanal fishing activities such as bottom set gillnet, push net, lead-fish trap net and shore seine are in detail discussed and the conservation measures which are urgently required are also presented.Not Availabl