Pradipta Pati
Biography
Dr. Pradipta Kumar Pati is a distinguished zoologist specializing in fishery biology, aquaculture, and applied biotechnology. He holds an M.Sc. and M.Phil. in Zoology from Ravenshaw University and a Ph.D. from Utkal University.
With over 25 years of teaching experience, Dr. Pati has served as a Lecturer at G.I. College, Shankarpur, and is currently a Professor (Grade A) at Christ College, Cuttack. He has 18 years of research experience and has published multiple papers in reputed journals, focusing on freshwater crab ecology, pesticide impact, and cryopreservation techniques.
Dr. Pati has actively participated in various national seminars and workshops, including UGC and ICAR-sponsored events. His research includes a Minor Research Project on the ecological role and conservation of rice field crabs in Eastern Odisha. Additionally, he has completed a UGC-sponsored refresher course at Utkal University.
Currently, Dr. Pati continues to contribute to academia and research, advancing knowledge in aquaculture and ecological conservation.
Research Interest
Despite their ecological and economic significance, there is a lack of comprehensive research on the morphometry, GSI index, behaviour of these species and culture plan in Chilika Lake. This study aims to investigate the morphometric characteristics, behavioural patterns, habitat preferences and culture practices of S. serrata and S. tranquebarica to hold significant economic value in estuarine and mangrove ecosystems.
Abstract
Morphometry, Behaviour and future culture practices of Scylla serrata and Scylla tranquebarica Crabs in Chilika Lake of Eastern Asia
Dr. Pradipta Kumar Pati P.G. Department of Zoology, Christ College, Affiliated to Utkal University, India -753008 Abstract Chilika Lake, a vital largest brackish water lake ecosystem in Eastern Asia, is home to diverse mud crab species, including the commercially export important varities named Scylla serrata (Chilika kankada, ver, P. K. Pati et. al. 1999 ) and Scylla tranquebarica (Green kankada, ver) crabs in the southern sector and the outer channel area. Now Scylla olivacea (red- orange mud kankada, ver) inhabits and adapts to the habitat conditions of the Chilika lake. Despite their ecological and economic significance, there is a lack of comprehensive research on the morphometry, GSI index, behaviour of these species and culture plan in Chilika Lake. This study aims to investigate the morphometric characteristics, behavioural patterns, habitat preferences and culture practices of S. serrata and S. tranquebarica to hold significant economic value in estuarine and mangrove ecosystems. A total of 500 specimens (250 of each species) were collected from different locations within Chilika Lake. Morphometric studies of these species show differences in carapace length (cl), carapace width (cw), body mass relationship, claw length and abdominal shape which affect their growth patterns, reproductive capabilities, predator-prey dynamics and body meat compositions.. Results showed significant differences in morphometric characteristics between S. serrata and S. tranquebarica. S. serrata exhibited larger carapace width and length with stronger claws while S. tranquebarica had features a more elongated carapace and lighter, more robust claws. The maximum size of S. serrata (185mm / 0.90kg) and S .tranquebarica (250 mm / 2.9 kg) recorded during the study which is considered as the largest sizes so far recorded from the lake from reviews. Behavioural observations were made on feeding, mating and burrowing habits. Habitat surveys indicated that S. serrata preferred mangrove forests, while S. tranquebarica inhabited mudflats and seagrass beds. Smaller crabs inhabit burrows, hardly lives in sub- tidal waters only at low tide and move into the intertidal zone mostly at high tide. Behavioural observations revealed distinct feeding patterns, with S. serrata preferring larger prey items. Both species exhibit territorial behaviour, burrowing tendencies and nocturnal activity. However, S. serrata displays more aggressive and dominant behaviour in interspecies competition while S. tranquebarica adapts through quick escape responses and flexible habitat choices. It is therefore pertinent to make a comparative study of the limnological conditions to ascertain any possible reason behind the decline in crab population of the Chilika lake. In environmental and limnological study, the activity of early crab stages ceases at temperatures below 15 °C. After moulting into the first crab stage, the tolerance of smaller sized crabs for lower salinities increases within a range of salinity 5 to 35 ppt, turbidity in cms.11 to 26 and pH 7.9 to 8.5. Their feeding strategies are influenced by seasonal changes in salinity, temperature and prey availability, impacting their dietary habits and ecological roles. The movement of mud crabs seems to be closely related to the kind of habitat they live. The traps like ‘Bintur’, ‘Tangkul’ and ‘Rakkang’ and ‘Baited-trap’ are extensively used for crab catching in the lake. The present findings have endorses for conservation and management efforts, particularly in the context of sustainable crab fishing practices along with their habitat restoration. Observed data can be utilized for biomass projection, spawning season determination, study of genetic diversity, reproductive biology and adaptive responses which is crucial for long-term sustainability. The findings have implications for strategic conservation regulation which is necessary to prevent over-exploitation, sustainable management of mud crab populations in Chilika Lagoon, ensuring the long-term health and resilience of the ecosystem, conditions for aquaculture practices and conservation strategies for germplasm. Keywords: Scylla serrata, Scylla tranquebarica, Scylla olivacea, Chilika Lake, morphometry, behavior, habitat preference, conservation.
