PORTUNUS PELAGICUS
Name of Fishery
Blue swimmer crab Fishery (Gear –Gill net)
Target Species
Portunus pelagicus
Location
INDIA – South East Coast ( Mandapam)
Fishing Area
FAO 57
Fishery History
(How long has the fishery been in operation? Describe changes in the fishery over time.)
Blue swimmer crab was using for local consumption since many years and hence fishery with traditional craft and gears must have started very long back. Exact details of its genesis not available and following literature give the details of fishery from the area.
Prasad and Tampi (1951) gave an account of the fishery and fishing methods for Neptunus pelagicus near Mandapam.
The crab fishery resources of India was given by Rao et al. (1973) and explained the fishery and fishing methods for Portunus pelagicus.
Ameer Hamsa (1978b) has described fishery of swimming crab P. pelagicus from Gulf of Mannar and Palk Bay.
Josileen, Jose and Menon, N G. 2007. Fishery and growth parameters of the blue swimmer crab Portunus pelagicus (Linnaeus, 1758) along the Mandapam coast, India. Journal of the Marine Biological Association of India, 49 (2): 159-165.
Stock Biology
(Stock size, structure, biomass, status, trends in population abundance, life cycle, growth, reproduction, schooling behaviour, etc.).
References are available for the size range and size composition in the fishery both in gill net and trawls, life cycle, growth, biological parameters etc.
Data on Target Species Population
(What sort of stock assessment information exists for this fishery? Is there a stock assessment? Is there catch per unit effort data? Landings data? Monitoring of biological indices? For how many years are data available? Who collects, manages, and stores the data? How are data collected?)
CMFRI regularly collects data from Trawl as well as from gillnet from Palk Bay and Gulf of Mannar. We have continuous trawl data from various canters whereas, gill net landings are rotation wise observed at various strata of nine zones of Ramanathapuram district of Tamil Nadu.
Fishing Activities
(Methods, gear, size/sex/season fished)
Gill net – throughout the year (OBBSGN and OBGN) and most of the centres of Palk Bay and Gulf of Mannar, gill net fishing is for four days Monday, Wednesday, Friday and Saturday. They use small country boats boats (Vathai) to large “Vallam” (14 OAL) including FRP boats.
Depending the size of the boat 3-4 persons are engaged in the fishing activity. Each person carries 3 nets of 30 length x 1m Width and spread in fleets, several of them tied end to end forming a long chain so that they cover a considerable area in the sea.
Fishermen go for fishing by1100-1200 hours, carrying the fleet of these nets and one person rudders the Vallam, while others lay the net at a depth of 4-15 metres always parallel to the coastal line. The nets will be in water for 15-18 hrs and fishermen comeback early morning hours and land the catches by 5AM. The fishing depth and distance from the shore vary from place to place and also capacity of the craft and fishermen. If storage facility is good fishermen keep the crabs in ice and stay for more than a day and for a maximum period of 3 days.
While in trawls crabs form a by catch and Portunus pelagicus are individually tied and landed and sold in live condition. Trawl fishing is banned during April- May, every year.
Fishing Activities
(Methods, gear, size/sex/season fished)
Gill net – throughout the year (OBBSGN and OBGN) and most of the centres of Palk Bay and Gulf of Mannar, gill net fishing is for four days Monday, Wednesday, Friday and Saturday. They use small country boats boats (Vathai) to large “Vallam” (14 OAL) including FRP boats.
Depending the size of the boat 3-4 persons are engaged in the fishing activity. Each person carries 3 nets of 30 length x 1m Width and spread in fleets, several of them tied end to end forming a long chain so that they cover a considerable area in the sea.
Fishermen go for fishing by1100-1200 hours, carrying the fleet of these nets and one person rudders the Vallam, while others lay the net at a depth of 4-15 metres always parallel to the coastal line. The nets will be in water for 15-18 hrs and fishermen comeback early morning hours and land the catches by 5AM. The fishing depth and distance from the shore vary from place to place and also capacity of the craft and fishermen. If storage facility is good fishermen keep the crabs in ice and stay for more than a day and for a maximum period of 3 days.
While in trawls crabs form a by catch and Portunus pelagicus are individually tied and landed and sold in live condition.
Volume Caught
*The catch varies from place to place and season/month. For example, in Thondi average catch of a unit in December 2016 was ≈15 kg per unit (total units -64) whereas, at Pasipattinam it was 7-8 kg/unit (total units -20).
*However, at present there is no continuous data available for gill nets from a centre.
Ecosystem Impacts
(Describe how the fishery interacts with the ecosystem, including gear interactions (e.g. habitat disturbance), species interactions (e.g. bycatch, endangered species, effects on the food web), etc. Include what is found in literature as well as the local perception of the impacts.)
Threats to Sustainability
(Describe any additional threats to the sustainability of this fishery (e.g. outsider encroachment, coastal development, etc.). Is there anything being done to address these threats?)
No management is in force and highly targeted species for export; 8-10 private companies are exclusively utilizing the resource for product development and being exported to one US company. Hence market demand is very high and indiscriminately exploiting the resource for the past 15-16 years, from this area.
Fishers
(Describe the group of fishers. Are they women or men? How many are there? How are they organized? To what extent do fishers profit from fishing? Are profits used to provide community infrastructure?)
Exact figures are not known.
Management Agencies
(Describe the roles that institutions, agencies, or local management bodies play in the management system and their interactions with each other.)
At present no concrete enforcement is in practice though there are possibilities are there!
Management Regime
(Describe how the fishery is managed. Include information for both national and local levels about rules, regulations, closed areas/seasons, quotas, limited entry/licenses, conflict resolution, adaptability, coping strategy/mitigation, etc. How often do mangers review rules and regulations? How would changes in the political regime affect management?)
At present gill net fishery has no management rules and regulations.
Management Compliance
(Do fishers comply with the management regime? How do managers ensure compliance? Are regulations actively enforced? Do fishers comply with international regulations for species conservation?)
No active steps have taken from the government side, though research institutions are in a position to suggest guidelines based on their many years studies on the species.
Community Participation in Management
(Describe how the community participates in the management of the fishery. Does the community set its own rules and regulations? How does this happen? Are they active in the governmental management system?)
Not practicing at present on a wider angle. Not sure whether any/few
Communities follow their own management system.
Processing and Marketing Information
(Once the product is landed, what happens to it? What is the chain from fishhook to consumer? Include how the product is processed and sold, and who processes and sells it. Where are the main markets for the fishery? Please also describe any buyers data that are available (e.g. quantity sold or exported, overall value); who collects, manages, and stores the data; how the data are collected; and the number of years for which data are available.)
Blue swimmer products are exclusively processed and exported to US and a group (8-10) of companies are involved in this and they have established an association, ICPA -Indian Crab Processors Association. Export Market is monopolised by a single US company. ICPA can give the details of buyers and exporters of Blue swimmer crab.
Interest in Certification
(Describe the fishery’s interest in certification. Are they interested? Why or why not?).
MSC certification initiative begun in November 2013 however, no further work/progress not made. ICPA is interested in certification as it becoming mandatory to export their products to US.
Stakeholders
(Who are the key stakeholders in this fishery (e.g. fishing organizations, processors, agents, buyers, researchers, NGOs, fisheries/natural resources management bodies, local authorities, etc.)? How many people are involved in the fishery (including fishers, processors, sellers, boat and gear manufacturers, managers, scientists, etc.)? What percentage of the human population within the coastal community depends on the fishery for their food or livelihood?)
Issues Requiring Special Attention
(Describe any local, regional or global controversies and/or conservation concerns that impact or involve the fishery.)
Additional Comments
(Include any additional information about this fishery or important to working with this fishery)
Sources