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Food and Agriculture Organization of the United Nations Fisheries and for a world without hunger Aquaculture Department

Cultured Aquatic Information Programme comes (Cantor, 1849)

I. Identity V. Status And Trends a. Biological Features VI. Main Issues b. Images Gallery a. Responsible Aquaculture Practices II. Profile VII. References a. Historical Background a. Related Links b. Main Producer Countries c. Habitat And Biology III. Production a. Production Cycle b. Production Systems c. Diseases And Control Measures IV. Statistics a. Market And Trade

Identity

Hippocampus comes Cantor, 1849 [] FAO Names: En - tail , Fr - Hippocampe à queue tigrée, Es - Caballo de mar oceánico

Biological features

Trunk compressed, more or less elevated, belly gibbous. Coronet small and rather low, with five rounded knobs. Anal minute. Pectoral short and broad. Dorsal moderate, situated on two trunk rings and one tail ring. Spines range from knob-like and blunt to well-developed and sharp; often with dark band near tip. Cheek spines are double. Double spines below and sometimes above eyes. Prominent, sharp nose spine; long, slender snout. Colour yellow and black body, sometimes alternating; striped tail; mottled or blotched pattern on body; may have fine white lines radiating from eye.

Images gallery

FAO Fisheries and Aquaculture Department Hippocampus comes Large scale production of (courtesy: Truong Si Ky. 2009) Nha Trang, Viet Nam

Large scale production of seahorses Fry production tanks (Viet Nam) Nha Trang, Viet Nam

Profile Historical background

Seahorses are under threat worldwide because of the global demand for them and products arising from them. It is claimed that nearly 80 nations trade 24 millions seahorses annually. Currently the largest threat to seahorses is their use in traditional Chinese medicines. Dead seahorses are milled and used as cures or remedies for human skin ailments, high cholesterol levels, excess throat phlegm, goitres, heart disease, lymph node disorders, incontinence and impotence. As seahorses retain their shape after being dried many are also sold as souvenirs. The largest markets for these products are , Europe, and Taiwan Province of China. Many are also taken for home aquaria but, being difficult to rear, most are lost. The Hippocampus comes is listed in Appendix II of CITES, effective May 2004. This species is particularly targeted by fishers for medicinal and purposes; it is also incidentally caught by trawlers. In the the population of this species has been reported to have decreased by up to 70 percent over the decade 1985-1995.

Culturing seahorses is one of the measures being taken to sustainably recruit this species and also to meet the demand for Traditional Chinese Medicines (TCM) and the aquarium trade. In Viet Nam, for conservation reasons, F1 broodstock are kept in cages where they produce a lot of fry daily for release into the sea.

Main producer countries

Although many countries, including Australia, China, , , New Zealand and the United States of America are reported to culture seahorses, primarily for the aquarium trade, the tiger tail seahorse is currently cultured only in Viet Nam.

FAO Fisheries and Aquaculture Department Habitat and biology

Tiger tail seahorses are mainly found in reefs, and , at a depth of 10-20 m. Juveniles prefer to live amonst and move to and sponges when they become older. Seahorse fry are pelagic and settle to the bottom when they are 35-40 mm. The fry feed on zooplankton, mainly , while adults prefer to catch benthic organisms (Amphipoda, Palaemonidae).

This species is found in the Western Central Pacific area, in China, Indonesia, , Philippines, , , and Viet Nam.

In its natural environment, Hippocampus comes spawns throughout the year but the peak spawning season varies according to their distribution. In Viet Nam, peak spawning lasts from August to November, but in Philippines it is later - from September to December. The first maturing size of H. comes is 119 mm in Viet Nam and 102 mm in Philippines. diameter averages 1.2-1.5 mm; duration is 10-14 days; length at birth averages 8-9 mm. In captivity the life cycle has been closed.

The von Bertalanffy equation shows H∞ = 165.9 mm and k = 0.78/year (Viet Nam) and SL∞ = 205 mm, k = 1.7/year (Philippines). Production Production cycle

Production cycle of Hippocampus comes

Production systems

Seed supply Broodstock are obtained by divers from the wild or from F1 generation maintained in captivity. The

FAO Fisheries and Aquaculture Department broodstock animals are kept in cages (2 x 2 x 4 m), located in calm sea in a bay or in indoor tanks (2 x 2 x 1.5 m). The feeding regime is the same as the maintenance feeding, but some vitamin A, C and E is added to the food. Broodstock become mature after six or seven months. In captivity, H. comes spawns many times per year (5-8 times) and the brood size ranges from 195 to 626 eggs (average 360). In the spawning season, females transfer their ripe eggs to the pouch of the males. Embryo development takes place in this pouch within 10-20 days, depending on the temperature of the water, the optimum being 26-28 oC.

One day after spawning, the fry are transferred, using a 1 mm mesh net, to 0.5 m3 plastic indoor tanks supplied with a biofilter, combined with UV and ozone treatment. The fry are stocked at 1-2/litre and the environmental conditions are maintained at 30-35‰; 4-5 ppm DO2; pH 8.0-8.3; light 12D/12L and 1 000-2 000 lux; zero ammonia-N and nitrite-N; <20 ppm nitrite-N.

The fry are fed from birth to 40-days old with copepods at a density of 3-5/litre/day. In addition, enriched Artemia nauplii (A1 DHA Selco, INVE) are fed to fry from 10 days onwards at the same as copepods. Some authors have described feeing seahorse fry with enriched rotifers and Artemia; however their survival rates are low, (20-30 percent), whereas feeding with enriched Artemia achieves >80 percent survival. Ongrowing techniques After 40 days of fry rearing the seahorses are transferred by net for rearing to commercial size in larger indoor tanks (2-4 m3) or outdoor cages placed in calm bay waters with high transparency. Initially the stocking rate is 500/m3 but is decreased as the fry grow to 200/m3 by the end of the rearing period. Tiger tail seahorses grow rapidly, reaching commercial size for aquaria (6-8 cm) in three months. The survival rate from birth to adult is >70 percent. It takes 10-12 months to rear them to their maximum size (12-16 cm). Feed supply During the grow-out phase the seahorses are weaned to frozen feed (Mysis and Acetes collected from the wild) twice per day fed ad libitum. If available, adult enriched live Artemia can be used, giving good growth and survival. Harvesting techniques All seahorses are harvested by net (typically with a 40 cm diameter and a 1 mm mesh size). Handling and processing All cultured seahorses in Viet Nam are packed in seawater with additional oxygen and transported at 3-5/litre for live sale to exporters, who sell them in the United States of America, European Union, Taiwan Province of China and Canada. Production costs Production costs to rear live 8-10 cm seahorses in Viet Nam is ~ USD 1.00 (2009).

Diseases and control measures

In some cases antibiotics and other pharmaceuticals have been used in treatment but their inclusion in this table does not imply an FAO recommendation.

DISEASE AGENT TYPE SYNDROME MEASURES Dip in 100-200 ppm Zoothamnium Occurs on seahorse tail; appears Ciliate infestation Protozoan formaldehyde for 12 hours, sp. like cotton repeating daily for 3 days Dip in 100-200 ppm Ichthyophthirus White spot sp. Protozoan White spots on body formaldehyde for 12 hours, repeating daily for 3 days External Gas Said to be Submerge below 2m; or Bubble Disease caused by gas Interferes with bouyancy and use Diamox 250 mg at a (EGBD) and saturation in the swimming; stresses the , Not stated dose of 1 tablet/200 L,

FAO Fisheries and Aquaculture Department Not stated dose of 1 tablet/200 L, Internal Gas water or by weakening them and eventually repeating treatment daily Bubble Disease infected causing death for 5 days (IGBD) bacteria Improve environment by External haemorrhages; using probiotic (Baccilus Vibriosis Bacterium haermorrhagic liver; ascitic fluid spp.) or using UV and accumulation in intestinal cavity ozone; antibiotic treatment (Ciprofloxin 5-10 ppm) First symptoms are Improve environment by discolouration and swelling in using probiotic (Bacillus spp.) Costia spp.; Bacteria and Snout and tail rot Saprolengia snout and tail; refusal to eat and or using UV and ozone; fungi spp. swim; lethargy; later, tip of snout antibiotic treatment becomes inflamed and eroded (Ciprofloxin 5-10 ppm) Improve environment by Variably sized white to yellow using probiotic (Bacillus spp.) Lymphocystis; Iridovirus Virus lumps (appear cauliflower or UV and ozone; antibiotic cauliflower disease shaped) on skin treatment (Ciprofloxin 5-10 ppm) Statistics Market and trade

Dried seahorses are used for traditional medicine and as curios. Live seahorses are sold for aquarium or hobbyist purposes. For aquaria the seahorses are marketed at >6 cm, but for TCM (Traditional Chinese Medicine) at 12-16 cm. Most dried seahorses are exported to China and to China, Hong Kong SAR. The value is USD 100-300/kg (2008), depending on the size and species; the larger animals are the most valuable. Live seahorses are exported to the United States of America and the European Union, mainly from Asian countries. The value of live seahorses ranges from USD 100-900/ (www.seahorse.com), depending of their colour, size and type of market. Annual live production has been relatively static at 2 millions individuals, while the dried seahorse production is said to be >20 millions (70 tonnes). Viet Nam and China are the major producers. This species has been bred successfully only since 2006 and only in Viet Nam. Until 2009, specific trade data on tiger tail seahorses is lacking but it is clear that most of the estimates 2 millions live animals destined for the aquarium trade come from the wild. Viet Nam is currently exporting about 50 000 live seahorses, of which about 10 000 are cultured. Status and trends The demand for live seahorses for aquarium use, as well as dried seahorses for TCM, is increasing globally; until now (2009) demand exceeds supply. The demand fo aquaria is relatively small but for TCM is considerable.

The following developments are required:

Selective breeding programmes for improving disease resistance. Improved techniques of aquaculture, in order to avoid . Increased awareness on the importance of seahorse conservation in communities to encourage the sustainable exploitation of seahorse resources.

Main issues Seahorses are mainly caught from the wild but these are threatened by overfishing and the degredation of their habitat. Seahorse resources have been reported to have declined by significant amounts during the first half of the 1990s (15-50 percent, depending on the specific areas or countries). Demand up to now exceeds supply and now many seahorse species are listed in CITES, Apendix II.

FAO Fisheries and Aquaculture Department Responsible aquaculture practices

Hippocampus comes is included in the IUCN Red List as vulnerable.

There are some programmes in Viet Nam releasing seahorses produced through aquaculture to the sea for enhancement. However, this may cause disease transfer to the wild seahorse population if not carefully controlled. Using many broodstock seahorses for aquaculture may also affect the recruitment population. About 1 000-2 000 juveniles are released annually in Viet Nam to marine areas where wild seahorses were formally found but have now disappeared. References Bibliography

Belli, M., Driscoll, C., Lamont, M. et al. 2006. Working notes: a guide to seahorse diseases. Creative Licence Publishers, USA.160 pp. Foster, S.J. & Vincent, A.C.J. 2004. Life history and ecology of seahorses: implications for conservation and management. Journal of Fish Biology, 65:1-61. Lourie, S.A., Pritchard, J.C., Casey, S.P., Ky, T.S., Hall, H.J. & Vincent, A.C.J. 1999a. The of ’s exploited seahorses (family Syngnathidae). Biological Journal of the Linnean Society, 66:231–256. Lourie, S.A., Vincent, A.C.J. & Hall, H.J. 1999b. Seahorses: an identification guide to the world's species and their conservation. Project Seahorse, London. 214 pp. Morgan, S.K. & Lourie, S.A. 2006. Threatened of the world: Hippocampus comes, Cantor 1850 (Syngnathidae). Environmental Biology of Fishes, 75:311-313. Morgan, S.K. & Vincent, A.C. 2007. The ontogeny of habitat associations in the tropical tiger tail seahorse Hippocampus comes Cantor 1850. Journal of Fish Biology, 71:701-724. Perante, N.C., Pajaro, M.G. & Vincent, A.C.J. 1998. Demographics of the seahorse Hippocampus comes in the Central Philippines. In B. Morton (ed.), The marine biology of the South China Sea. Proceedings of the Third International Conference on the Marine Biology of the South China Sea, Hong Kong, 28 October - 1 November 1996, pp. 439-448. Hong Kong University Press, Hong Kong. Perante, N.C., Pajaro, M.G., Meeuwig, J.J. & Vincent, A.C.J. 2002. Biology of a seahorse species Hippocampus comes in the central Philippines. Journal of Fish Biology, 60:821–837. Salin, K.R., Yohannan, T.M. & Nair, C.M. 2005. Fisheries and trade of seahorses, Hippocampus spp., in southern India. Fisheries Management and Ecology, 12:269-273. Truong, S.K. 1998. Prospects for community-based seahorse aquaculture in Viet Nam. In B. Morton (ed.) The marine biology of the South China Sea. Proceedings of the Third International Conference on the Marine Biology of the South China Sea, Hong Kong, 28 October - 1 November 1996, pp. 465 – 474. Hong Kong University Press, Hong Kong. Truong, S.K., Ho, T.H., Hoang, D.L. & Pham, V.L. 2009. The effect of different kind of feed on the growth and survival rates of adult tiger tail seahorse (Hippocampus comes, Cantor, 1885). Journal of Marine Science and Technology, 2:71-80. Vincent, A.C.J. 1996. The International trade in Seahorses. Cambridge, UK: TRAFFIC International. 163 pp. Vincent, A.C.J. 2004. Summary of the 2003 IUCN Red listings for family Syngnathidae. Proceedings of International wookshop on CITES implementation for seahorse conservation and trade. February 3 – 5. 2004. Mexico. Related links

FishBase FAO Fisheries and Aquaculture Department FAO FishStatJ – Universal software for fishery statistical time series Project Seahorse The IUCN Red List of Threatened Species Seahorse Vietnamese academy of science and technology

FAO Fisheries and Aquaculture Department