226
J. Nabhitabhata
eggs (Chotiyaputta 1995; Sundaram and Khan 2011; Unnithan 1982). Spawning
occurs throughout the year with seasonal peaks varying on geographical localities,
environment and habitats. The maximum length is about 125 mm with an estimated
lifespan of 720 days (Reid et al. 2005; Roper et al. 1984). The final size and lifespan
tend to be shorter in the estuarine populations.
This is an economically important species of the region, especially in India and
Sri Lanka, with captures representing between 2 and 4 % of the total cephalopod
catch in India (Sundaram and Khan 2009, 2011), and 3 % (approximately 2,000 t)
of total cuttlefish catch in Thailand (Supongpan 1995). They are mostly captured
by trawlers offshore and by push nets inshore and in the estuary (Supongpan 1995).
Average capture sizes range between 40 and 60 mm in India and between 20 and
80 mm in Thailand. The estimated age to reach this size is 180 days with a growth
rate of 2.5 mm per month (Sundaram and Khan 2009; Unnithan 1982).
The spineless cuttlefish has a more active behaviour than other sepiid cuttlefish.
They ritually hover in the water column like a pelagic squid and dwell on the bottom
like other cuttlefish. The behaviour is aggressive to a higher degree than the pharaoh
cuttlefish. The spineless cuttlefish sometimes bite others in the same school, as well
as humans when handled with bare hands (Nabhitabhata et al. 1984, 1985). Because
of their benthic–pelagic habit, spineless cuttlefish require less interindividual space
or territory compared with pelagic squid of the same size, and can be maintained
at a higher density. Considering the unique life history and behaviour, this species
would have to be named the “active cuttlefish”.
Aspects related to aquaculture potential of this species were reported at both laboratory scale (Boonprakob et al. 1977a, b; Anil 2003) and large scale (Nabhitabhata
1997, 2000; Nabhitabhata et al. 1984, 1985; Sivalingam 1999). The small final size
turns out to be an advantage for frozen human food product processing and packaging and ornamental aquarium displays, as in Sepia pharaonis (see Chap. 12, this
volume). The high tolerance to variation of environmental conditions makes the
spineless cuttlefish biologically interesting from a large-scale culture point of view.
Furthermore, this species is a less selective feeder, and can be trained to accept dead
feed easier than pelagic squid in culture tanks.
13.2 State of the Art
The spineless cuttlefish is highly tolerable to fluctuations of the environment and
has a high adaptability to culture conditions. This species can be cultured through
several consecutive generations in tanks in flow-through systems. Broodstocks collected from the wild can spawn in captivity. Egg masses are collected and nursed
under controlled environment until hatching after about 13 days at 28°C. The hatching rate and survival of the young at 30 days are higher than 95 %. Hatchlings are
fed with wild-collected live feed for about 30 days, but training them to accept dead
feed can be as early as 20 days. Water volume and culture density are managed
to correspond with their rapid growth and high survival during the nursing phase.
J. Nabhitabhata
eggs (Chotiyaputta 1995; Sundaram and Khan 2011; Unnithan 1982). Spawning
occurs throughout the year with seasonal peaks varying on geographical localities,
environment and habitats. The maximum length is about 125 mm with an estimated
lifespan of 720 days (Reid et al. 2005; Roper et al. 1984). The final size and lifespan
tend to be shorter in the estuarine populations.
This is an economically important species of the region, especially in India and
Sri Lanka, with captures representing between 2 and 4 % of the total cephalopod
catch in India (Sundaram and Khan 2009, 2011), and 3 % (approximately 2,000 t)
of total cuttlefish catch in Thailand (Supongpan 1995). They are mostly captured
by trawlers offshore and by push nets inshore and in the estuary (Supongpan 1995).
Average capture sizes range between 40 and 60 mm in India and between 20 and
80 mm in Thailand. The estimated age to reach this size is 180 days with a growth
rate of 2.5 mm per month (Sundaram and Khan 2009; Unnithan 1982).
The spineless cuttlefish has a more active behaviour than other sepiid cuttlefish.
They ritually hover in the water column like a pelagic squid and dwell on the bottom
like other cuttlefish. The behaviour is aggressive to a higher degree than the pharaoh
cuttlefish. The spineless cuttlefish sometimes bite others in the same school, as well
as humans when handled with bare hands (Nabhitabhata et al. 1984, 1985). Because
of their benthic–pelagic habit, spineless cuttlefish require less interindividual space
or territory compared with pelagic squid of the same size, and can be maintained
at a higher density. Considering the unique life history and behaviour, this species
would have to be named the “active cuttlefish”.
Aspects related to aquaculture potential of this species were reported at both laboratory scale (Boonprakob et al. 1977a, b; Anil 2003) and large scale (Nabhitabhata
1997, 2000; Nabhitabhata et al. 1984, 1985; Sivalingam 1999). The small final size
turns out to be an advantage for frozen human food product processing and packaging and ornamental aquarium displays, as in Sepia pharaonis (see Chap. 12, this
volume). The high tolerance to variation of environmental conditions makes the
spineless cuttlefish biologically interesting from a large-scale culture point of view.
Furthermore, this species is a less selective feeder, and can be trained to accept dead
feed easier than pelagic squid in culture tanks.
13.2 State of the Art
The spineless cuttlefish is highly tolerable to fluctuations of the environment and
has a high adaptability to culture conditions. This species can be cultured through
several consecutive generations in tanks in flow-through systems. Broodstocks collected from the wild can spawn in captivity. Egg masses are collected and nursed
under controlled environment until hatching after about 13 days at 28°C. The hatching rate and survival of the young at 30 days are higher than 95 %. Hatchlings are
fed with wild-collected live feed for about 30 days, but training them to accept dead
feed can be as early as 20 days. Water volume and culture density are managed
to correspond with their rapid growth and high survival during the nursing phase.