Recent Submissions

  • Conference paper

    Fisheries, cultivation and research aspects of mud crab (Genus Scylla) in China 

    GZ Wang - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Mud crabs are distributed only along the coastal areas of southeast China. Of the four Scylla species found in China, Scylla paramamosain is the dominant species. The annual wild catch of mud crabs in mainland China was 60,000-70,000 mt. The highest annual production from farming was 120,000 mt.

    The main species cultured is S. paramamosain. Fattening (involves the feeding of immature female crabs until their ovaries become mature), polyculture and monoculture are commonly practiced. Farming is done in earthen ponds and pens in intertidal zone and mangrove area. The seeds for farming are mostly from the wild and only about 10% are sourced from the hatchery. Occurrence of diseases and differences in the population are the main problems in mud crab farming in China. At present, research activities on mud crab that are being undertaken include reproductive biology, hatchery and farming technology. Further research on the prevention of diseases and development of formulated diets (ingredient selection, nutritional requirements, pellet size, shape and stability) are necessary.
  • Book | Conference publication

    Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India 

    ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.) - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
  • Conference paper

    Molecular genetic approaches to resolve taxonomical ambiguity of mud crab species (Genus Scylla) in Indian waters 

    A Mandal, M Varkey, SP Sobhanan, AK Mani & YC Thampi Sam Raj - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Mud crab or mangrove crab (Genus Scylla de Haan) is one of the most extensively cultured and economically important brachyuran crabs from the family Portunidae in Indo-Pacific countries, including India. Mud crabs exhibit variations in colour, size, spination, polygonal pattern and habitat. These contribute to the confusion in their identification. Accurate identification of the species is essential in the breeding programmes of domesticated stocks and is a crucial factor in the success of stock enhancement programmes. The taxonomic uncertainty of the genus Scylla in India is still an issue and several papers are being published using misleading identification. This is the first attempt to resolve the taxonomical ambiguity of mud crabs commonly found in Indian waters using multiple molecular genetic approaches. ITS-1, RAPD, PCRRFLP and mt-DNA sequencing along with traditional morphometric methods were used. Furthermore, a PCR method was developed by which mud crab species in India could be identified rapidly and accurately. The results of gene sequencing along with other molecular markers clearly indicated that the ‘green’ morph of Indian mud crab is S. serrata, while the ‘brown’ one is S. olivacea which was validated using the revised classification of mud crabs by Keenan et al. (1998). The S. serrata commonly mentioned in published literatures from India is S. olivacea and the S. tranquebarica, as believed by many Indian researchers, should be classified as S. serrata. Therefore, caution should be taken while interpreting or implementing the biological, molecular and aquaculture data published in those literatures.
  • Conference paper

    Development of practical diet for the grow-out culture of Scylla serrata in ponds 

    MR Catacutan, MF Mallare & ET Quinitio - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    A series of feeding experiments were conducted in the laboratory and in ponds of SEAFDEC/AQD using hatchery-produced Scylla serrata juveniles to develop an effective pelleted grow-out diet. The practical feed ingredients included local and imported fishmeal, shrimp meal, copra meal, soybean meal, corn grits and squid liver powder. The other feed ingredients were rice bran, wheat pollard, bread flour and micronutrient mixes. The results in the laboratory trials were used to improve the feed composition for the culture of crab juveniles in grow-out ponds. Three runs (Run 1 - 108 days, Run 2 - 129 days and Run 3 - 114 days) were conducted in 270m2 ponds. Crab juveniles at stocking densities of 0.08 - 0.10m-2 were fed two dietary treatments containing 44% and 38% crude protein at similar dietary energy level estimated at 17 MJ/kg diet.

    There were no significant differences in the survival, growth and feed conversion ratio in each of the three runs. In Run 1, the survival rate of crabs fed with 44% protein was higher (56-77%) than crabs fed with 38% protein (35-50%), but these were not significantly different. In Run 2, < 5 g crabs could grow up to a mean body weight of 435 g with survival rates of 31- 45% after 129 days on a ration consisting of 80% pelleted formulated feed and 20% low value fish. Similarly in Run 3, a mean of 443 g was attained in less than 4 months with survival rates of 30-73%. The final average weight and specific growth rate of crabs fed these two diets were not significantly different which showed that in ponds, the 38% crude protein diet was able to sustain growth as with the 44% diet provided the dietary energy is similar. The feed conversion ratio for both test diets and low value fish showed a great variation (low value fish 1 to 4; test diets 1.81 to 5.6).

    This study showed that low value fish as the traditional feed for mud crab in the grow-out culture can be decreased to only 20% of the ration by incorporating 80% of formulated pelleted feed.
  • Conference paper

    Scylla species found in Cochin backwaters, Kerala, South India 

    PL Devi & A Joseph - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    The present study described the Scylla species collected from Cochin backwaters for two years from June 2010 to May 2012. Identification and description of Scylla species were carried out based on the morphological characters focusing on the first and second male gonopods, and third maxillipeds.

    The first male pleopods of the three species were found to be similar in shape, but variations were observed in the setation pattern. S. serrata and S. tranquebarica showed two patches of setae on the inner margin on its posterior end, which was thin and inconspicuous in the former, while thick and conspicuous in the latter. S. olivacea was found to possess only a single tuft of thick setae on the inner margin of the first male pleopod. The second male pleopods were similar in S. serrata and S. tranquebarica, while found to be varied in S. olivacea. The second male pleopods were found to possess setation on the inner margin on its posterior region in S. olivacea, which was totally absent in S. serrata and S. tranquebarica. There were no significant variations in the third maxillipeds among the three Scylla spp. The third maxillipeds of three Scylla spp. were characterized by broad and flattened merus and ischium, lined with thick hairs on the inner margin.

    The present study shows the occurrence of three species, Scylla serrata, S. tranquebarica and S. olivacea, in Cochin backwaters. However identification of species needs to be confirmed using molecular techniques.
  • Conference paper

    Mud crab nursery rearing practices 

    FD Parado-Estepa, ET Quinitio & EM Rodriguez - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    The need for seeds for expansion of the mud crab industry led to the development of the hatchery technology. The nursery technology was developed as this served as a link between the hatchery, which produces megalopae or early crab instars, and the grow-out phase which requires bigger crab juveniles for a higher yield. The nursery has two phases, the first ending with production of crablets with 1- 1.5 cm carapace width (CW) and the second phase with crablets of 2.5-3.0 cm ICW. The more commonly recommended system employs stocking of megalopae or crab instars in net cages installed in ponds. Locally available unprocessed food and commercially available shrimp formulated diet are used for feeding. However, recent studies have successfully used formulated nursery diet for mud crab. One of the main problems in the nursery is cannibalism, and several strategies have been investigated and tried to address the problem.
  • Conference paper

    Reproductive biology of mud crab Scylla tranquebarica found in Ratnagiri coast, Maharashtra, India 

    SD Naik, SS Sonawane, AS Pawar & SP Hotekar - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    The study was carried out to determine the reproductive biology of the mud crab Scylla tranquebarica to provide baseline information that are useful in the seed production activities.

    Size at first maturation was observed in male crabs with 11 cm carapace width (CW) and in female crabs with 10 cm CW. The highest GSI values in male crabs (6.17) and females (5.12) were observed in October. The maximum number of eggs produced by females was up to 5 million. The egg diameter ranged from 0.69 to 0.76 mm at the heartbeat stage. Embryonic development was classified into five major stages: blastula, gastrula, nauplius pigmentation and heartbeat. The color of newly spawned eggs was orange. As the embryo developed, the color changed from orange to brown and finally to black prior to hatching. The incubation period was 11-13 days and the hatching success was 80%. The temperature and salinity during the incubation period ranged from 27 to 30°C and 30 to 35 ppt, respectively.
  • Conference paper

    Culture of Scylla serrata (Forskal) in cement ponds 

    AS Kotiya, JB Solanki & NG Akolkar - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Male and female Scylla serrata juvenile crabs were stocked separately in cement ponds (14 x 8 x 0.8 m; 90 m3) and reared for 90 days. The study was conducted at the Fisheries Research Station, JAU. Okha, Gujarat. The crabs were fed trash fish and Trochus spp.

    The survival rates of male and female crabs were higher in Run 1 at 66.11% and 45.55%, respectively, than in Run 2 at 13.9% and 6.1%, respectively. The mean body weights of males (1,704 g) and females (994.5g) in Run 1 were higher compared to those in Run 2 (381.2 g for males and 104.5 g for females). However, there were no significant differences (P>0.05) in the average daily weight gain of 0.19 g day-1 for males and 0.13 g day-1 for females in Run 1 and 0.16 g day-1 for males and 0.13 g day-1 for females in Run 2. The water parameter levels were within the optimum ranges for mud crab culture.

    The results indicate that it is not commercially viable to grow juveniles to market size in cement ponds based on the conditions in this study.
  • Conference paper

    Status of mud crab industry in Thailand 

    S Nooseng - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Mud crab is an economically important crustacean commodity in Thailand due to its high nutritional and market value. All the four species of mud crab, Scylla paramamosain, S. olivacea, S. serrata and S. tranquebarica are found in Thailand. The production areas are along the coasts of Gulf of Thailand where S. paramamosain or white mud crab is abundant, and Andaman Sea where S. olivacea or black mud crab is dominant. Data from the Thai Department of Fisheries estimated that the total mud crab production in 2010 was 2,130 mt valued at Baht 322.7 million (US$10.84 million). In the last decade, the production from coastal aquaculture was 6,921 mt valued at Bath 491.4 million (US$16.51 million). The probable cause of the decrease in production is the over exploitation of the wild population.

    Mud crab culture systems commonly practiced are grow-out (culture from juveniles to market size crabs in ponds), fattening of lean crabs and production of soft-shell crabs. In the past, seedstocks for grow-out culture were collected from the wild. Recently, both wild and hatchery-reared seedstocks are being utilized for farming. Mud crabs for fattening and production of soft-shell rely mainly on wild resources. All culture practices are considered extensive or semiintensive except for soft-shell crab farming which is intensive.

    The current research and development activities include broodstock and seed production techniques, and formulated feed production. Further technical and financial support are required to improve the survival and production of mud crab. Likewise, support for the transfer of technology to farmers is needed. The lack of seed supply is a major issue facing the mud crab industry in Thailand. A few mud crab hatcheries, which belong to the government, have been established. It is becoming difficult to collect ovigerous females from the wild. Hence, most females are obtained from ponds. Collection of ovigerous females in the wild is prohibited from October to December. Restocking of mud crabs in the natural habitat has become a routine activity to increase the resources.
  • Conference paper

    Status of mud crab industry in India 

    YC Thampi Sam Raj, A Mandal, G Kumaran, A Sethuramalingam, P Srinivasan & J Kumar - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Mud crab is an economically important portunid crab species found in estuaries, coastal lagoons and nearshore waters of India. The genetics team of RGCA recently made an attempt to decipher the taxonomic ambiguity of mud crab species commonly available in Indian coastal waters using multiple molecular genetic markers and concluded that only two species of mud crabs, Scylla serrata and S. olivacea are commonly available in India.

    India has about 8,103 km of coastline with shallow coastal waters, brackishwater lakes, estuaries and intertidal swampy areas along the east and west coasts. It has been estimated that the potential resources of crabs particularly from the 7,770 km2 of estuaries and backwaters is 13,209 tonnes out of the total potential resources of 43,816 tonnes from Indian coastal waters. The southern part of the coast is potentially richer than the northern part. Estimated brackish water area in India is about 1,190,900 ha, out of which 167,193 ha developed for shrimp farming may become suitable for crab farming as evidently seen in Tuticorin, Tamil Nadu. Estimated mud crab culture area in Andhra Pradesh is more than 2,833 ha covering nearly 50 villages. Live mud crab export from India was higher in 2011-2012 (3,054 mt) compared to 2010-2011 (2,963 mt). Frozen and other forms of crab export declined in 2011-2012 (2,848 mt) compared to 2010- 2011 (3,251 mt). Apart from shrimp culture, mud crab farming, fattening and soft-shell crab production are now emerging as feasible business ventures in India. About 11 types of crab products are being exported from India with an average unit value realization of US$ 3.73 kg−1, highlighting its importance in the foreign exchange earnings.

    There has been a noticeable decline in the mud crab populations in the natural habitat throughout Indian coastal waters due to over exploitation and indiscriminate fishing of juvenile crabs by artisanal fishermen. Wild seeds are collected throughout the year in backwater zones of Sundarbans, Kakdwip and Namkhana of West Bengal; Chilika Lake of Odisha; coastal waters of Kakinada, Visakhapatnam and Rajahmundry of Andhra Pradesh; Pulicat Lake, Killai backwaters, Muthupet saline swamps, Punnakayal estuarine complex and Colachel coastal waters of Tamil Nadu; Neendakara, Cochin and Kozhikode backwaters of Kerala to meet the demand of culture operations. There is an urgent need to produce good quality hatchery seed to meet the demand of farmers. To address this, the Rajiv Gandhi Centre for Aquaculture (RGCA) established a state-ofthe- art mud crab hatchery for commercial scale production of seedstock to promote the adoption of the technology by the private entrepreneurs in the country.
  • Conference paper

    Status of mud crab industry in the Philippines 

    ET Quinitio - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Mud crab farming has long been established in the Philippines. Scylla serrata, S. tranquebarica and S. olivacea are the common species found in the Philippines. S. serrata is the preferred species for farming by crab growers. The total production of mud crab from aquaculture was estimated at 13,720 valued at US$77,025,000 and 14,437 tons valued at US$86,511,000 in 2009 and 2010, respectively. The sources of crab seeds for farming are from the wild and in recent years, from the hatchery although in small percentage. The overexploitation of mud crabs and habitat losses have resulted in both reduced landings and mean capture size. To stem the wild harvest, the provincial and municipal government along with the Bureau of Fisheries and Aquatic Resources have introduced ordinances that prohibit the gathering and selling of crablets (≤ 3 cm) outside the municipality of origin. This resulted to increased acceptability of hatchery-reared crabs by crab growers.

    Basic technologies in all phases of culture (hatchery, nursery and grow-out) have been developed. However, there are still several issues that need to be addressed. In the hatchery phase, one of the major causes of low survival are the Molt Death Syndrome in which zoea 5 has difficulty molting to megalopa and diseases due to bacterial and fungal infection in eggs and larvae. The use of antibiotics as treatment for Vibrio spp. has proven to improve larval survival. However, the use of antibiotics can lead to the development of resistant strains of bacteria and abnormalities that become apparent at the juvenile stage.

    In the nursery phase, economic losses have been attributed to cannibalism. Providing sufficient food and shelters, reducing stocking density, size grading and removal or trimming of claws are the common strategies used to mitigate the high level of cannibalism. Recent findings showed that incorporating tryptophan in the diet can reduce the aggressive behavior of crabs. In the grow-out phase, culture of juvenile crabs to market size with one or two more commodities in earthen brackishwater ponds is the most prevalent practice. Due to the cannibalistic nature of mud crab, polyculture (usually with milkfish and shrimp) pond is carried out. Stocking density of each commodity varies with the size and the number of seed stock available and the abundance of natural food growth in the pond. Culture period ranges from 4-5 months. Monoculture of crabs is usually done for short term culture as in fattening in various systems. Mud crab culture is also integrated with the existing mangroves. Formulated diets have been verified in commercial grow-out ponds and showed promising results. Mud crabs are commonly fed with low value fish, molluscs and other unprocessed natural foods. Mortality in mud crabs in grow-out phase is oftentimes due to the white spot syndrome virus.

    The domestication of S. serrata has been done at SEAFDEC/AQD. The duration from spawning of the base population to F1 broodstock size was 10-14 months and from F1 to F2 was 11-12 months. Selective breeding of S. serrata is currently being done. The results serve as guide to understand and eliminate the obstacles to broodstock management and seed production. Recently, The Department of Science and Technology has funded the National Mud Crab Science and Technology Program being implemented by SEAFDEC/AQD and University of the Philippines Visayas to refine the existing technologies in all phases of culture and to aggressively promote the establishment of several mud crab hatcheries and nurseries in the Philippines. The Bureau of Fisheries and Aquatic Resources is also implementing the Philippine National Aquasilviculture Program, which includes the rehabilitation of mangrove forests and culture of commercially important aquatic animals including mud crab in established mangrove areas. On-site training on all phases of culture of mud crab has also been done by SEAFDEC/AQD not only in the Philippines but also in other countries like Brunei, Myanmar, India and Timor Leste. With the establishment of several hatcheries and nurseries, there will be sufficient seed stock supply for farming, thereby decreasing the dependence on wild stock.
  • Conference paper

    Soft-shell crab production using hatchery-produced mangrove crab Scylla serrata juveniles 

    K Ganesh, GK Dinakaran, T Sundaresan, K Satheesh Kumar, KV Gangadharan, S Viswanathan, S Pandiarajan & YC Thampi Sam Raj - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Soft-shell crab production is being practiced in many Asian countries but the major source of seedstock is from the wild, which could no longer sustain the increasing demand. Commercial scale soft-shell crab production can become sustainable only if there is a continuous supply of seedstock not dependent on wild stock. Rajiv Gandhi Centre for Aquaculture (RGCA) under the Marine Products Export Development Authority (MPEDA) has established a pilot-scale mud crab hatchery at Thoduvai, Nagapattinam District, Tamilnadu in 2004 with the technical assistance from SEAFDEC/AQD. At present, RGCA has the biggest mud crab hatchery in India and a demonstration farm at Karaikal, U.T. of Puducherry, where nursery rearing, grow-out and soft-shell crab production are conducted using hatchery- produced mangrove crabs or mud crabs, Scylla serrata. This paper presents the results of the soft-shell crab production using hatcheryproduced S. serrata juveniles maintained in perforated low density polyethylene (LDPE) boxes. The duration of the molt interval, time of molt (day or night) and the increase in body weight and carapace width of each size group (40-60, 61-80, 81-100, 101-120, 121-140, 141-160, 161-180 g) after molting were determined.

    Results showed that the percentage increase in body weight and carapace width increased as the crabs grew bigger. Likewise, the molt interval was longer in bigger-sized groups of crabs. Sixty to seventy percent of the population molted during night time and the next molt occurred within 25 days in 80-160 g size groups. Soft-shell crabs in boxes within the water surface and juvenile crabs (2.5 cm CW initial size) for culture until market size in the pond can be a viable technology technology for mud crab growers.
  • Conference paper

    Effect of tank color on the survival of mud crab Scylla serrata larvae 

    MA de los Santos, T Taro, D Uehara, I Dwight & L Masami - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    The survival rate of mud crab or mangrove crab Scylla serrata larvae was evaluated using black and yellow-painted tanks. About 400,000 zoea 1 were stocked in 6 tons of treated seawater. The larvae were initially fed with rotifers and subsequently with newly hatched Artemia until the megalopa stage. The larval rearing water was enriched with a combination of Spirulina powder and frozen micro-algal products that include Nannochloropsis sp., Tetraselmis sp. and Thallasiosira weissfolgii. After 15 to 17 days of rearing, the larvae successfully molted to megalopa stage. A total of 377,062 megalopae were harvested. Although the survival rate of megalopae was higher in yellow tanks (23.63± 0.03%), it was not significantly different when compared to those in black tanks (15.66±0.02%) (P=0.05).
  • Conference paper

    Mass seed production of mud crab Scylla serrata at Rajiv Gandhi Centre for Aquaculture 

    M Saravanan, S Arul Raj, K Manivannan, S Pandiarajan & YC Thampi Sam Raj - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Mass seed production of mud crab Scylla serrata adopting the best management practices has been done in the hatchery of Rajiv Gandhi Centre for Aquaculture, Thoduvai in Tamil Nadu. Mature female mud crabs from farms and landing centres were procured, screened for White Spot Syndrome Virus and conditioned in the hatchery. The crabs were subjected to unilateral eyestalk ablation whenever necessary and maintained in tanks with sand substrate and aeration. The crabs were fed fresh squid, oyster meat and low value fish.

    Hatching occurred 9 days after spawning. The newly hatched zoeae were stocked in 5-ton tanks at 80 ind/li. The larvae were fed rotifers and Artemia nauplii. Green water culture system with the use of probiotics was adopted. Enrichment of Artemia was carried out. A hatchery run ranged from 25-30 days. The highest survival rate achieved was 17.5%. This could propel the commercialization of mud crab seed production in India.
  • Conference paper

    Status of mud crab aquaculture in Bangladesh 

    MS Islam - In ET Quinitio, FDP Estepa, YC Thampi Sam Raj & A Mandal (Eds.), Proceedings of the International Seminar-Workshop on Mud Crab Aquaculture and Fisheries Management, 10-12 April 2013, Tamil Nadu, India, 2015 - Rajiv Gandhi Centre for Aquaculture (MPEDA)
    Bangladesh has about 710 km of coastlines with 618,780 ha of mangrove tidal flats and 80,000 ha of associated areas which are suitable for brackishwater aquaculture. Mud crab culture has been practiced for many years in the coastal regions, particularly in southeast (Chittagong, Cox’s Bazar, Chokoria and Noakhali) and southwest (Khulna, Bagherhat and Satkhira) Bangladesh. In 1981, crab export became a stable business which ranked third among the fisheries export earnings. Bangladesh earns about US$6 million per year by exporting 1,500 metric tons of live mud crabs to Singapore, Hong Kong, China, Taiwan and Japan.

    Mud crab has been an incidental product arising from the culture of shrimps and other finfishes in ponds. Mud crabs were first exported in 1977 and since then farmers focused their attention to this species as an alternative to shrimp. However, mud crab farming is still dependent on wild resources. As the demand of mud crab in the international market increased, the number of crab gatherers also significantly increased. In addition, gathering of sub-adult crabs for fattening contributed to the depletion of adult crabs as breeders. Since the wild resources are under threat, management of resources and establishment of hatcheries are needed to sustain the mud crab industry in Bangladesh.