Taxonomic notes: Section empty

Hippocampus erectus is distributed in the western Atlantic from the southern tip of Nova Scotia, Canada (rare) south along the U.S., Bermuda, the Bahamas, and throughout the Gulf of Mexico and Caribbean Sea. Records east of the Orinoco River are now considered H. patagonicus (Fritzsche and Vincent 2002, Boehm et al. 2013). It has also been collected from Banco Acores (Azores Archipelago) in the eastern Atlantic (Woodall et al. 2009). Its depth range is 0-73 m (Dias et al. 2002, personal observation TLD ILR, Vari 1982).

Project Seahorse trade surveys conducted between 2000–2001 indicated that seahorse numbers in the wild appear to have declined in the Western Atlantic (Caribbean and Gulf of Mexico), with fishers reporting decreases in catch of seahorses (proportion of declines that can be attributed to H. erectus is unknown). On the coast of Mexico 21/29 fishers in five locations reported declines in seahorses due to the shrimp trawl fishery. Of the 14 fishers who provided quantified catch estimates, eight estimated declines between 75–90% in the past 10–30 years (J. Baum unpublished data). In Brazil 25/29 fishers surveyed reported declines in seahorse catches due to heavy fishing pressures (I. Rosa, unpublished data). In Honduras 70% of interviewed fishers (n=9) believed there has been a decline in abundance (J. Baum, unpublished data). While we recognize that these surveys and reported population declines do not encompass the global range of H. erectus, we have chosen to take the precautionary approach of assigning VU.
Hippocampus erectus has variable forms and may represent more than one species. Specimens from Argentina and Brazil appear to be genetically distinct from north Atlantic specimens, and may prove to be a separate species (Lourie et al. 2004, Casey in litt. to S. Lourie). 85 specimens were collected for dried and live trades weighing 0.19-12.02g and they were 8.1-19.4cm in height (Baum and Vincent 2005). Between July 1998 and June 1999, 916 specimens were caught as bycatch by bait shrimp fishermen. In 1999, the amount of lined seahorses incidentally caught decreased. this was in correlation to the absence of the largest class of males as well as an increase in the amount of smaller sized females. But, this is attributed to spatial structuring because the location where the larger specimens were caught were not revisited at the end of the year. Evidence over two years shows that there is a female-biased sex ratio, with the average being only 40-42% males (Baum et al. 2003). In Tampa Bay, Florida, between Dec. 2005 and Dec. 2007 there were a total of 5 specimens spotted with a 0.09% frequency (Masonjones et al. 2010).
It is not common off Mexico in the Gulf of Mexico (M. Vega-Cendejas pers. comm. 2013).

Hippocampus erectus occurs in water up to 73 m, and is associated with aquatic vegetation such as mangroves (mostly Rhizophora mangle and Avicennia sp.), Caulerpa spp., Carijoa sp., seagrass (Thalassia testudinum, Halophila sp.), floating Sargassum, and sponges usually relying on these substrates as holdfasts (Dias et al. 2002, Lieske and Myers 1994, McAllister 1990 in Lourie et al. 1999, Fish and Mowbray 1970). Hippocampus erectus can be found at the surface and bottom of both shallow water and deeper areas of channels in bays, along beaches, in or near salt marshes, and over oyster beds and weed-covered banks (Hardy 1978). In Brazil it has been found in salinity of 45% (Dias et al. 2002). Seahorses are not usually found in such a great variety of habitats, geographical range, and depth, making this a very unique species (Kuiter 2009).

This species may be particularly susceptible to decline. The limited information on habitat suggests they inhabit shallow sea-grass beds (Lourie et al. 1999) that are susceptible to human degradation, as well as making them susceptible to being caught as bycatch. All seahorse species have vital parental care, and many species studied to date have high site fidelity (Perante et al. 2002, Vincent et al. in review), highly structured social behaviour (Vincent and Sadler 1995), and relatively sparse distributions (Lourie et al. 1999). The importance of life history parameters in determining response to exploitation has been demonstrated for a number of species (Jennings et al. 1998).

The maximum size for Hippocampus erectus is 18.5cm; the maximum reported height at onset of sexual maturity is 5.6cm and males can brood up to 400 eggs. The average brood size for this species is 250 to 300 eggs (Fritzsche 2002, Baum  et al. 2003). Hippocampus erectus matures during the first reproductive season after birth, six to twelve months of age and has a gestation period of 20–21 days, varying with water temperature (Lourie et al. 1999). The egg diameter is 0.15cm and the young approximately 0.9cm long at birth (Vincent 1990). The reproductive period for this species is apparently from May to October. The number of eggs/embryos inside the brood pouch of males with a total length ranging from 8cm to 12.6cm, from 97 to 1,552; number of prehydrated oocytes in females with a total length ranging from 6cm to 12.3cm, from 90 to 1,313. Newborns are released by ejection from the brood pouch by body contortions and pumping action of the pouch (Teixeira and Musick 2001). 
This species is a resident of Gray's Reef National Marine Sanctuary, where its eggs occur in a non-pelagic region, larvae are found in both coastal and inner-shelf and in pelagic regions, juveniles are found in the inner-shelf, mid-shelf, outer-shelf, and on the slope, are found among benthic vegetation as well as pelagic vegetation and submerged sediment, and adults are located in the estuarine, coastal, inner-shelf, mid-shelf, and outer-shelf regions and are also found among pelagic vegetation and submerged vegetation as well as coral, rocky and oyster reef habitats (Hare et al. 2006).

This species is known to develop elaborate skin fronds and males have proportionally longer tails than do females (Baum et al. 2003, Lourie et al. 2004).

Hippocampus erectus is an important species in aquarium and medicinal trades (Zhang et al. 2010). This species is used in domestic folk medicine and souvenir trades, and domestic and international aquarium trades in Mexico, Brazil, and for domestic trades in Central America. Hippocampus erectus is also taken as by catch in shrimp trawl fisheries in the USA, Mexico, and Central America, some of which is retained for export for use in the Traditional Chinese Medicine trade (Dias et al. 2002). This species has been reared successfully in captivity; this has in part been the result of increasing culture efforts since all 33 recognized Hippocampus spp. species were listed on Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora, due to overexploitation of the wild populations to meet growing demand in Chinese medicine and ornamental market (Zhang et al. 2011, CITES 2004, Lourie et al. 1999, Vincent 1996).    
Hippocampus erectus is one of more than ten seahorse species to have been successfully reared in captivity and is recognized as a good candidate for commercial aquaculture (Zhang et al. 2010, Correa et al.1989, Lin et al. 2008).
Seahorses also provide more tractable study taxa than many other small fish species due to their limited movement and site fidelity (Foster and Vincent 2005). About 95% of the seahorses in trade are used in TCM; as China’s population continues to grow rapidly, the demand for syngnathid products has followed (West 2012).  
Between January 1995 and November 2000, there were 12,586 specimens that were traded as marine aquarium fishes in Fortaleza, Ceara, Brazil, making this species 6.31% of all of the fishes reported being traded during these years (Monteiro-Neto et al. 2003).  The numbers of live Hippocampus erectus that were traded internationally and recorded in the CITES trade database are 160 from captivity, 59,156 - 62,114 from the wild, and 13,650 from unknown origins (Koldewey and Martin-Smith 2010).  85 specimens of H. erectus were collected for the live trades as well as the dried trades on the Atlantic coast of Latin America. Dried seahorses were usually sold unadorned or as key chains. Occasionally some of them were sold as jewelry, shell crafts with shells and sea stars, or as 'dragons' with wings and eyes attached. These dried seahorses were sometimes ground and consumed in a drink as folk medicine to treat asthma. Chinese populations in Panama and Peru sold seahorses commercially as medicine, for use as TCM. The live seahorses were traded as aquarium fishes. Also, in some countries, including Honduras and Costa Rica, they had in situ value because dive masters would take tourists to particular sites where these seahorses were located. It is believed that most live trades occur almost entirely on the black market, thus meaning that no records have been kept of the fishery or trade (Baum and Vincent 2005). A study conducted to see how icthyofauna are used in traditional medicine in Brazil reports several uses of this species. The  entirety of each specimen is used for therapies including athsma, alcoholism, thromboses, bronchitis, impotence, osteoporosis, heart disease, cancer, and rheumatism. It is used in 6 bodily systems by people in Brazil and has a relative importance of 0.985 (El Deir et al. 2012).

Hippocampus erectus is traded dried as traditional medicine, curios, and live for aquariums (Vincent and Perry in prep.). This is a popular aquarium fish in North America. In Florida alone, thousands of H. erectus are collected each year for the aquarium trade (P. LaFrance unpublished data). Hippocampus erectus is Brazil’s 6th most important marine ornamental export (Monteiro-Neto et al. 2000). In addition to being sold as TM, H. erectus are sold as curios in Mexico along the Caribbean coast (J. Baum unpublished data). Hippocampus erectus are often brought up as bycatch by shrimp trawling operations in Florida (Baum et al. 2003), and in Mexico seahorse population declines are attributed to indirect harvesting by the shrimp trawl fishery (J. Baum unpublished data). In Central America H. erectus are brought up in the shrimp trawls in Belize, Honduras, and Nicaragua, and are exported as TCM, or sold on both coasts as curios (J. Baum unpublished data). Similarly in South America H. erectus are among the bycatch of shrimp trawls in Mar del Plata, Argentina (L. Magnasco in litt. to A. Vincent 23 May 1999), and in Brazil (I. Rosa and J. Baum unpublished data).

The preferred habitat of H. erectus is also declining due to coastal development, pollution, and increased sedimentation. For example, in NE Brazil the development of shrimp farms has destroyed much of the coastal mangrove habitats where seahorses live (J. Gomezjuardo in litt. to A. Vincent Sept. 1999).

• 1.3 Tourism & recreation areas
• 1.2 Commercial & industrial areas
• 1.1 Housing & urban areas
• 5.4.6 Motivation Unknown/Unrecorded
• 101.20 OLD 3.5.3 Harvesting (hunting/gathering)->Cultural/scientific/leisure activities->Regional/international trade
• 101.19 OLD 3.5.2 Harvesting (hunting/gathering)->Cultural/scientific/leisure activities->Sub-national/national trade
• 101.18 OLD 3.5.1 Harvesting (hunting/gathering)->Cultural/scientific/leisure activities->Subsistence use/local trade
• 100.43 OLD 6.3 Pollution (affecting habitat and/or species)->Water pollution
• 100.20 OLD 4.1.1.2 Accidental mortality->Bycatch->Fisheries related->Netting

The entire genus Hippocampus was listed in Appendix II of CITES in November 2002; implementation of this listing began May 2004. Full monitoring of the trade is underway in the United States, however this is dependent on traders’ declarations. Seahorses are listed under Title 68 (Rules of the Fish and Wildlife Conservation Commission) of the Florida Administrative Codes. The targeted fishery for the aquarium trade in Florida is monitored and regulations are in place, such as a limitation on the number of commercial harvesters, however the non-selective exploitation is not monitored in any state. Hippocampus erectus is considered threatened in the states of Sao Paulo and Rio de Janeiro in Brazil. Their status has not been evaluated in the other states.  
Between the years of 1986 and 1998, the Coral Cay Conservation reported that Hippocampus erectus had a rare abundance in 7 proposed or established Marine Protected Areas where it was recorded: Turneffe Atoll, South Water Cay Marine Reserve, Sapodilla Cays, Snake Cays, and other unspecified areas (Harborne 2000). H. erectus has been frequently captured as bycatch by shrimp bait fishermen and it has been proposed to introduce seasonal and area closures (Baum et al. 2003).

• 100.4 OLD 1.1.2 Policy-based actions->Management Plans->Implementation
• 100.3 OLD 1.1.1 Policy-based actions->Management Plans->Development
• 4.3 Awareness & communications
• 4.2 Training

Global:Hippocampus erectus is listed as Vulnerable (VU A4cd) based on inferred declines of at least 30% caused by targeted catch, incidental capture, and habitat degradation. While there is little information on changes in numbers of the species, there is indirect evidence to suggest that declines have taken place and are continuing. This listing is consistent with the precautionary approach of the IUCN.

Hippocampus erectus is traded for use as aquarium fishes, curios and traditional Chinese medicine (TCM) (Vincent and Perry in prep.). This species is also incidentally caught, as bycatch, in shrimp trawl and other fisheries in Florida (Baum et al. in review), Mexico (J. Baum, unpublished data), Central America (Belize, Honduras, Nicaragua) (J. Baum, unpublished data) and South America (Argentina, Brazil) (I. Rosa and J. Baum, unpublished data). This species is also affected by habitat degradation due to coastal development and pollution. Given that H. erectus is among the most commonly traded seahorse species, particularly for ornamental display, fishers' and traders' evidence of declines in seahorse availability raise concern for this species.
Western Central Atlantic:This species is widely distributed throughout the western central Atlantic to Venezuela in a variety of shallow habitats, but commonly associated with aquatic vegetation. Certain habitats, such as seagrass beds are experiencing degradation. It is susceptible to shrimp trawls and is sought after by the aquarium and medicinal trades. There is evidence that significant population declines have occurred. It is listed on CITES Appendix II. Therefore, the global listing of VU under A4cd is retained. Assessors: Jeff Williams, Jorge Brenner, Riley Pollom. Facilitator: Gina Ralph. Date assessed: 10 January 2014

Gulf of Mexico: This species is widely distributed throughout the Gulf of Mexico in a variety of shallow habitats, but commonly associated with aquatic vegetation. Certain habitats, such as seagrass beds are experiencing degradation. It is susceptible to shrimp trawls and is sought after by the aquarium and medicinal trades. It is listed on CITES Appendix II and is regulated off the United States and Mexico bans export. There is evidence that significant population declines have occurred, therefore, this species is listed as VU under A4cd.

• Baillie, J. and Groombridge, B. (eds). 1996. 1996 IUCN Red List of Threatened Animals. pp. 378. International Union for Conservation of Nature, Gland, Switzerland and Cambridge, UK.
• Barletta, M. and Correa, M.F.M. 1989. Chondrofauna do complexo estuarino da baía de Paranaguá e adjacências, PR – Brasil. Levantamento e produtividade pesqueira. In: Summaries of the IV Meeting of the Work group on Fishes and Research of Sharks and Rays in Brazil, Tamandaré. p: 23. (in Portuguese).
• Baum, J.K. and Vincent, A.C.J. 2005. Magnitude and inferred impacts of the seahorse trade in Latin America. Environmental Conservation 32(4): 305-319.
• Baum, J.K., Meeuwig, J.J. and Vincent, A.C.J. in review. By-catch of lined seahorses (Hippocampus erectus) in a Gulf of Mexico shrimp trawl fishery. Fishery Bulletin. 101(4): 721-731.
• Boehm, J. T., Woodall, L., Teske, P. R., Lourie, S. A., Baldwin, C., Waldman, J., & Hickerson, M. 2013. Marine dispersal and barriers drive Atlantic seahorse diversification. Journal of Biogeography 40(10): 1839-1849.
• CITES. 2004. Seahorses and other members of the family Syngnathidae. Twentieth meeting of the Animals Committee 17. Johannesburg (South Africa).
• Dias, T.L., Rosa, I.L, and Baum, J.K. 2002. Threatened fishes of the world: Hippocampus erectus Perry, 1810 (Syngnathidae). Environmental Biology of Fishes 65(3): 326.
• El-Deir, A.C.A., Collier, C.A., Neto, M.S.D.A., Silva, K.M.D.S., Policarpo. I.D.S., Araujo, T.A.S., Alves, R.R.N., Albuquerque, U.P.D., and Moura, G.J.B.D. 2012. Ichthyofauna Used in TraditionalMedicine in Brazil. Evidence-Based Complementary and Alternative Medicine 2012: 1-16.
• Felicio, A.K.C., Rosa, I.L., Souto, A., and Freitas, R.H.A. 2006. Feeding behavior of the longsnout seahorse Hippocampus reidi Ginsburg, 1933. Japan Ethological Society and Springer-Verlag Tokyo 2006(24): 219-225.
• Fish, M.P. and Mowbray, W. H. 1970. Family Syngnathidae 070: pipefishes and seahorses. In: Sounds of Western North Atlantic Fishes. Johns Hopkins Press: Baltimore. 205 pp.
• Foster, S.J. & Vincent, A.C.J. 2005. Enhancing Sustainability of the International Trade in Seahorses with a Single Minimum Size Limit. Conservation Biology 19: 1044-1050.
• Fritzsche, R. 2002. Syngnathidae. In: K.E. Carpenter (ed.), The Living Marine Resources of the Western Central Atlantic, pp. 1221-1225. FAO, Rome.
• Fritzsche, R.A., and Vincent A. 2002. Order Gasterosteiformes Syngnathidae.
• Harborne, A. 2000. Fish and Coral Species Lists Compiled by Coral Cay Conservation: Belize 1990-1998. In: Harborne, A. (ed.). Coral Cay Conservation Ltd., London.
• Hardy, J.D. 1978. Development of Fishes of the Mid-Atlantic Bight. Three Volumes. U.S. Fish and Wildlife Service, Office of Biological Services.
• Hare, J.A., Walsh, H.J., Maranick, K.E., Score, D., Sedberry, G.R., Parker Jr, R.O., and Mays, R.W. 2006. Fish fauna of Gray’s Reef National Marine Sanctuary and the implications for place-based management. .
• IUCN. 2003. 2003 IUCN Red List of Threatened Species. www.iucnredlist.org. Downloaded on 18 November 2003.
• Jennings, S., Reynolds, J.D. and Mills, S.C. 1998. Life history correlates of responses to fisheries exploitation. Proceedings of the Royal Society of London Series B 265:333-339.
• Kells, V. and Carpenter, K.E. 2011. A Field Guide to Coastal Fishes - From Maine to Texas. John Hopkins University Press, Baltimore, MD.
• Koldewey, H. J. and Martin-smith, K. M. 2010. A global review of seahorse aquaculture. Aquaculture 302: 131-152.
• Kuiter, R.H. 2009. Seahorses and their relatives. Aquatic Photographics, Seaford, Australia.
• Lieske, E and Myers, R.F. 1994. Collins Pocket Guide. Coral reef fishes. Indo-Pacific and Caribbean including the Red Sea. Harper Collins Publishers, New York, USA.
• Lin, Q., Lin, J., and Zhang, D. 2008. Breeding and juvenile culture of the lined seahorse, Hippocampus erectus Perry, 1810. Aquaculture 277(3-4): 287-292.
• Lourie, S.A., Foster, S.J., Cooper, E.W.T. and Vincent, A.C.J. 2004. A Guide to the Identification of Seahorses. Project Seahorse and TRAFFIC North America, University of British Columbia and World Wildlife Fund, Washington D.C.
• Lourie, S.A., Vincent, A.C.J. and Hall, H.J. 1999. Seahorses: an identification guide to the world's species and their conservation. Project Seahorse, London, U.K.
• Masonjones, H.D., Rose, E., McRae, L.B., Dixson, D.L. 2010. An examination of the population dynamics of syngnathid fishes within Tampa Bay, Florida, USA. Current Zoology 56(1): 118-133.
• McAllister, D.E. 1990. A working list of fishes of the world. Canadian Museum of Nature, P.O. Box 3443, Ottawa, Ontario K1P 6P4, Canada.
• Monteiro-Neto, C., Cunha, F.E.A., Nottingham, M.C., Araújo, M.E., Rosa, I.L. and Barros, G.M.L. 2003. Analysis of the marine ornamental fish trade at Ceará State, northeast Brazil. Biodiversity and Conservation 12: 1287-1295.
• Monteiro-Neto, C., Ferreira, B.P., Rosa, I.L., Rocha, L.A., Araújo, M.E., Guimarãe, R.Z.P., Floeter, S.R. and Gasparini, J.L. 2000. The marine aquarium fisheries and trade in Brazil. A preliminary report submitted to IUCN. Fortaleza, Brazil.
• Perante, N.C., Pajaro, M.G., Meeuwig, J.J. and Vincent, A.C.J. 2002. Biology of a seahorse species Hippocampus comes in the central Philippines. Accepted by Journal of Fish Biology. 2001.
• Vari, R.P. 1982. Fishes of the Western North Atlantic, part 8. Order Gasterosteiformes, suborder Syngnathoidea. Syngnathidae (Doryrhamphinae, Syngnathinae, Hippocampinae). Yale University, New Haven, CT, USA.
• Vincent, A.C.J. 1996. The International Trade in Seahorses. TRAFFIC International, Cambridge, UK.
• Vincent, A.C.J. and Sadler, L.M. 1995. Faithful pair bonds in wild seahorses, Hippocampus whitei. Animal Behaviour 50: 1557-1569.
• Vincent, A.C.J., Evans, K.L., and Marsden, A.D. 2005. Home range behaviour of the monogamous Australian seahorse, Hippocampus whitei. Environmental Biology of Fishes 72: 1–12.
• West, K. 2012. Investigations into the Senegalese trade in CITES-listed seahorses, Hippocampus algiricus. Imperial College London.
• Woodall, L.C., Koldewey, H.J., Santos, S.V. and Shaw, P.W. 2009. First occurrence of the lined seahorse Hippocampus erectus in the eastern Atlantic Ocean. Journal of fish biology 75: 1505-1512.
• Zhang, D., Yin, F, and Lin, J. 2011. Criteria for assessing juvenile quality of the lined seahorse, Hippocampus erectus. Aquaculture 322-323: 255-258.
• Zhang, D., Zhang, Y., Lin, J., and Lin, Q. 2010. Growth and survival of juvenile lined seahorse, Hippocampus erectus (Perry), at different stocking densities. Aquaculture Research 42: 9-13.