WWW.WAS.ORG • WORLD AQUACULTURE • DECEMBER 51 including pilot-scale facilities in the now-closed National Resource Center for Cephalopods (NRCC, University of Texas Medical Branch, USA) and CCMar (University of Algarve, Portugal) and, to some extent, in extensive aquaculture (Sequi 1980, Palmegiano and Sequi 1981, Palmegiano and Sequi 1984, Sequi and Palmegiano 1984). European cuttlefish has characteristics that justify this species as an aquaculture candidate, such as large eggs (easily transported and maintained), hatchlings that do not go through a larvae stage, high survival in captivity, tolerance of high densities, handling and shipping, low levels of reported pathologies and morphological abnormalities, and short life cycles (CCMar produces two generations per year), all of which translates into rapid growth rates and 3 months to investment payback. Nevertheless, the species also has some constraints, such as being semelparous (spawning only once per life cycle) with low fecundity (about 6000 eggs/female), and it is an intelligent carnivorous species with high metabolism. Although it requires food with a high protein content, cuttlefish is selective regarding the food offered. Research on Cuttlefish Culture at CCMar The primary objective is to obtain biological knowledge and develop technology to culture cuttlefish as an alternative species for commercial aquaculture. Our secondary objective is to, within the framework of the European Marine Biological Resource Centre (EMBRC, www.embrc.eu), highlight the value of the species for its use in a variety of research and commercial areas. CCMar has been taking a multi-disciplinary approach to develop cuttlefish culture. The following lines of research have been expanding from the first experiments performed in 2000 until the present. From 2000 to 2006, we developed zootechnology protocols for each life stage and determined prey needs. Between 2006 and 2010, a greater effort was invested to determine the nutritional needs of cuttlefish at each life stage and to enhance reproductive performance. Since 2010, we have been assessing the effects of population genetics on reproduction and expanding our knowledge regarding animal welfare and behavior in captivity. Currently we are developing a prepared diet and started commercial, pilot-scale trials. The most current version of cuttlefish culture protocols is included as a chapter in a forthcoming book “Cephalopod Culture” that will be published by Springer. Major Achievements and Work in Progress Egg stage During the last 13 years of research, we have substantially improved the hatching percentage. After being laid on nets by females (Fig. 1), eggs are individually removed and separated before being placed in hatching tanks. Embryonic development requires between 25 days at 25 C to 30 days at 20 C (Sykes et al. 2006a). The hatching tank must be supplied with sufficient levels of aeration to keep eggs moving and maintain adequate dissolved oxygen levels (Sykes et al. 2006b). In this way, egg spoilage is reduced and hatching rate is increased (Sykes et al. 2012c). A study of eggs from natural and captive populations indicated no differences in lipid content and use (Sykes et al. 2009). Hatchling stage Hatchlings may be fed a variety of prey species, including Artemia spp. and the mysid shrimp Paramysis nouvelli (Domingues et al. 2001b), the shrimp Crangon crangon (Domingues et al. 2003a), the fish Atherina spp. (Domingues et al. 2004), but grass shrimp Palaemonetes varians gives the best results (Domingues et al. 2003b) and was established as the only prey needed for cuttlefish culture throughout the life cycle (Sykes et al. 2006a). Frozen food (Fig. 2) can be used from the first day after hatching (Sykes et al. 2012b). At this stage, cuttlefish growth rates of 15 percent body weight/day can be attained, supported by feeding rates of 35-50 percent body weight/d. The species tolerates a wide temperature range (10-32 C; Domingues et al. 2001a, Domingues et al. 2002). Hatchlings should be reared in black tanks (Sykes et al. 2011), at low incident light intensities (100 lux) or reflective light intensities below 10 lux (Sykes et al. 2013), and at densities less than 500 hatchlings/m2 (CONTINUED ON PAGE 52) FIGURE 3. Raceways used for the rearing of the hatchling stage (Photo: A. Sykes). FIGURE 4. Cuttlefish juveniles reared in a 6000-L (A) and a 1500-L (B) round tanks, being fed a prepared diet (C) and congregating (D) (Photos: A. Sykes).
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