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J. Nabhitabhata and S. Segawa
The cephalopod seeds are collected for release during the next day. The water
in the nursing tanks is drained through the centre pipe into a 50-L tank with an immersed hand scoop for reducing the flow rate and collecting the cephalopods. With
aeration from a portable air pump, the tank with seeds is transported to the selected
releasing sites.
The total numbers of released seeds was 25.95 million over 14 years (1990–2003):
23.06 million for bigfin squid, 2.77 million for pharaoh cuttlefish and 1.08 million
for other species (Table 7.2). The average number released was 2.14 million seeds
per year. About 90 % of the seed was the bigfin squid and the remaining 10 % was
mostly pharaoh cuttlefish but included other species.
7.3.2.2 In situ Seed Production
The project is being conducted by a community of squid-trapping fishermen who are
aware of the need to conserve their livelihood through the conservation of natural resources. The first trial, the so-called Cephalopod Seed Bank, was conducted in June
2012, in Chumporn Province, southern Thailand, Gulf of Thailand. The activity was
funded by the Thailand DOF with technical consultation by the Prince of Songkla
University. The eggs were collected from traps owned by the fishermen themselves.
The idea was to incubate the collected egg capsules in field conditions. The egg
capsules were placed in net bags made from fishing net of 0.5 cm mesh size (Fig. 7.8).
Each bag was about 50 cm long and 30 cm in diameter. The bags were hung from a
rope with a 30-cm interval at one end and kept suspended with a 100-mm plastic float
at the other end. Seven strings of rope were fastened to the frame that was made from
iron pipes and floated with empty polyvinyl chloride (PVC) barrels. A net cage of
300 × 200 × 200 cm, 0.5 cm mesh size was also hung from this frame to serve as a fence
for the egg bags. The ‘set’ was then covered by a piece of shutter net to reduce excess
light. The sites were selected by the community. In order to reduce the cost, bamboo
frames were used as a substitute for the iron pipe frame. This project has been continued up to the present time and has been extended to neighbouring fishing communities.
The advantage is that there is little cost for the hatchery operation. The fisherman
will stop by the site during his homeward journey and put his collected egg capsules
into the bags. The hatchlings pass through the mesh into natural waters, using the
floating facility as a temporary shelter for primary acclimatization. This method
can also be applied for aquaculture as an in situ nursery of eggs and hatchlings that
requires little expense and is cost effective compared to a land-based hatchery.
7.4 Conclusions
Aquaculture to restock cephalopods has been performed by public sectors in both
Japan and Thailand with a long history of about 50 years. The restocking activities are based on public awareness about the depletion of natural resources. Most
J. Nabhitabhata and S. Segawa
The cephalopod seeds are collected for release during the next day. The water
in the nursing tanks is drained through the centre pipe into a 50-L tank with an immersed hand scoop for reducing the flow rate and collecting the cephalopods. With
aeration from a portable air pump, the tank with seeds is transported to the selected
releasing sites.
The total numbers of released seeds was 25.95 million over 14 years (1990–2003):
23.06 million for bigfin squid, 2.77 million for pharaoh cuttlefish and 1.08 million
for other species (Table 7.2). The average number released was 2.14 million seeds
per year. About 90 % of the seed was the bigfin squid and the remaining 10 % was
mostly pharaoh cuttlefish but included other species.
7.3.2.2 In situ Seed Production
The project is being conducted by a community of squid-trapping fishermen who are
aware of the need to conserve their livelihood through the conservation of natural resources. The first trial, the so-called Cephalopod Seed Bank, was conducted in June
2012, in Chumporn Province, southern Thailand, Gulf of Thailand. The activity was
funded by the Thailand DOF with technical consultation by the Prince of Songkla
University. The eggs were collected from traps owned by the fishermen themselves.
The idea was to incubate the collected egg capsules in field conditions. The egg
capsules were placed in net bags made from fishing net of 0.5 cm mesh size (Fig. 7.8).
Each bag was about 50 cm long and 30 cm in diameter. The bags were hung from a
rope with a 30-cm interval at one end and kept suspended with a 100-mm plastic float
at the other end. Seven strings of rope were fastened to the frame that was made from
iron pipes and floated with empty polyvinyl chloride (PVC) barrels. A net cage of
300 × 200 × 200 cm, 0.5 cm mesh size was also hung from this frame to serve as a fence
for the egg bags. The ‘set’ was then covered by a piece of shutter net to reduce excess
light. The sites were selected by the community. In order to reduce the cost, bamboo
frames were used as a substitute for the iron pipe frame. This project has been continued up to the present time and has been extended to neighbouring fishing communities.
The advantage is that there is little cost for the hatchery operation. The fisherman
will stop by the site during his homeward journey and put his collected egg capsules
into the bags. The hatchlings pass through the mesh into natural waters, using the
floating facility as a temporary shelter for primary acclimatization. This method
can also be applied for aquaculture as an in situ nursery of eggs and hatchlings that
requires little expense and is cost effective compared to a land-based hatchery.
7.4 Conclusions
Aquaculture to restock cephalopods has been performed by public sectors in both
Japan and Thailand with a long history of about 50 years. The restocking activities are based on public awareness about the depletion of natural resources. Most