Taxonomic Notes
The 1996 and 2000 IUCN Red Lists included Hippocampus horai, H. novaehebudorum, H. raji, and H. taeniops. These are now all considered to be synonyms of H. kuda. According to Vincent (1996) and Lourie et al. (1999), there may be as many as ten distinct species that are included under the name Hippocampus kuda. Further research into the literature on this species is needed to determine whether H. kuda is the correct name for populations occurring within the Persian Gulf (T. Munroe pers. comm. 2014).
Justification
There is some taxonomic uncertainty surrounding the population of Hippocampus kuda in the Persian Gulf. In the Persian Gulf, Hippocampus kuda is known from Kuwait, Saudi Arabia, Bahrain, and northeast of Qatar. However, the full extent of its range in the Persian Gulf is not well understood. Hippocampus kuda inhabits a variety of shallow, coastal water habitats including seagrasses, reefs, and macroalgae. Due to its mode of spawning, fecundity in this species is comparatively low compared to non-brood pouch spawning fishes and therefore its capacity for population growth is more limited than other species. Furthermore, since there is no broadcast spawning of pelagic eggs, dispersal of potential recruits is limited. Additionally, given the limited swimming abilities of seahorses, it is highly unlikely that rescue effects would occur from adjacent populations. Throughout the Persian Gulf, there has been degradation of coastal habitats, including seagrasses and coral reefs, which this species is known to utilize. There are no known species-specific conservation measures in place for Hippocampus kuda. However, there are several marine protected areas within its distribution, including the Jubail Marine Wildlife Sanctuary, where Hippocampus kuda has been recorded. Oceanographic data suggests that a rescue effect through the Strait of Hormuz is negligible. Little is known on the population and current status of this species' habitat, therefore, Hippocampus kuda is listed as Data Deficient. Studies that improve our knowledge regarding the taxonomy, geographic distribution, and habitat preferences of this species within the Persian Gulf, as well as, a reliable estimate of abundance are needed to make a proper conservation appraisal.
Geographic Range Information
In the Persian Gulf, Hippocampus kuda is known from Kuwait, Saudi Arabia, Bahrain (Kuronuma and Abe 1972, 1986; Al-Baharna 1986, Krupp and Müller 1994) and northeast of Qatar (Kuronuma and Abe 1986).
Population Information
To date there have been no underwater or trade surveys conducted in the Persian Gulf for Hippocampus kuda. The species has been reported as common in the past in and around coral reefs in the Persian Gulf (Kuronuma and Abe 1972). Oceanographic data suggests that a rescue effect through the Strait of Hormuz is negligible.
Habitat and Ecology Information
Hippocampus kuda is found in shallow inshore waters normally between 0-8 m depth with a maximum recorded depth of up to 55 m (Lourie et al. 2004). Hippocampus kuda inhabit coastal bays, harbours and lagoons, sandy sediments in rocky littoral zones, macroalgae and seagrass beds, mangroves, muddy bottoms, and shallow reef flats. Hippocampus kuda is one of six seahorse species known to inhabit estuaries and brackish waters. Hippocampus kuda has also been recorded from open water and attached to drifting Sargassum up to 20 km away from land (Kuiter and Debelius 1994). In the Persian Gulf, Hippocampus kuda is common in and around coral reefs (Kuronuma and Abe 1972). Feeds on zooplankton, especially crustaceans (Paulus 1999). The maximum reported length is 30 cm. Males incubate young in a brood pouch (Foster and Vincent 2004). Males carries the eggs in brood pouches and give birth to live young. Brood pouch size in pipefishes regulates fecundity, which is much lower than for a broadcast spawning species (Breder and Rosen 1966, Dawson 1985, Paulus 1999, Browne et al. 2008).
Hippocampus kuda may be particularly susceptible to decline due to habitat degradation and its vulnerable life history characteristics. Coastal development, destructive fishing practices, and pollution occur throughout seahorse habitat in the Indo-Pacific region (Short et al. 2011). For example, in Malaysia, Hippocampus kuda numbers declined due to an extensive port development around the Pulai Estuary that destroyed large tracts of seagrass meadow (Vincent et al. 2011). All seahorse species have vital parental care, and many species studied to date have high site fidelity (Perante et al. 2002, Vincent et al. 2005), highly structured social behaviour (Vincent and Sadler 1995), and relatively sparse distributions (Lourie et al. 1999). These life history parameters often make species susceptible to exploitation as has been demonstrated for a number of species, including seahorses (Jennings et al. 1998, Foster and Vincent 2004). Although seahorses also have some traits, such as small body size, fast growth and high fecundity, that may confer resilience to exploitation pressures (Morgan 2007), their specialised life-history coupled with a dependence on shallow habitats that are subject to extremely high fishing pressure, and the fact that seahorses do not move very much and are thus easily captured, means they are very vulnerable to over-exploitation.
Threats Information
Hippocampus kuda is caught and traded for traditional medicines, aquaria and curios throughout its range (Perry
et al. 2010). However, the extent to which this occurs in the Persian Gulf is unknown.
Globally a major threat to seahorses is industrial trawling. Indiscriminate trawling leads to habitat loss and bycatch, both of which are known to impact seahorse populations (Vincent
et al. 2011). Bycatch levels for this species in the Persian Gulf have not been quantified, although it has not turned up in local studies of Bushehr or Hormuzgan fishing grounds (Raeisi
et al. 2011, Kazemi
et al. 2013).
Throughout the Persian Gulf, seagrass beds have sustained extensive damage and loss due to extensive coastal development, sedimentation, trawling activities, and dredging during the construction of offshore man-made island structures. Adjacent to these sites, even non-dredged vegetated habitats are impacted by increased sedimentation associated with the dumping of dredge spoil at and around the original dredge sites. Coral substrata in the Persian Gulf is limited, but also have suffered damage (Sheppard
et al. 2010).
Due to its mode of spawning (ovoviviparous brood pouch male parental care), fecundity in this species is comparatively low compared to non-brood pouch spawning fishes and therefore its capacity for population growth is more limited than other species. Furthermore, since there is no broadcast spawning of pelagic eggs dispersal of potential recruits is limited. Additionally, given the limited swimming abilities of seahorses, it is highly unlikely that rescue effects would occur from adjacent populations (Browne
et al. 2008).
Use and Trade Information
Hippocampus kuda is considered valuable for traditional medicine purposes, curios and aquaria (Perry et al. 2010). This may be due to its large size, smooth texture, and pale complexion when dried (Vincent 1996), all desirable qualities for seahorses to be used for traditional medicine purposes. Trade in this species is extensive. Since the implementation of the listing of all Hippocampus species on CITES Appendix II (2004), trade in this species alone has been recorded at over 2 million individuals per annum (Evanson et al. 2011, UNEP-WCMC 2012a). International trade 2004-2010 consisted primarily of live animals and dried bodies, with smaller quantities of specimens and derivatives also reported (UNEP-WCMC 2012a). Trade was principally wild-sourced and captive-born (Evanson et al. 2011, UNEP-WCMC 2012a). The vast majority of trade was for commercial purposes, and the main range States involved in exporting were Vietnam, Thailand and China (Evanson et al. 2011, UNEP-WCMC 2012a). The United Arab Emirates are listed as one of the major importers of dried Indian seahorses (Salin et al. 2005). Historically, high levels of trade in Hippocampus kuda were reported from India from 1992 until the ban of seahorse exports in 2001 (Marichamy et al. 1993, Vincent 1996, Sreepada et al. 2002). Actual global trade in Hippocampus spp. is thought to be significantly higher than the legal trade reported (Nijman 2010, Vincent et al. 2011). Koldewey and Martin-Smith (2010) reported that demand for Hippocampus spp. could not yet be met through aquaculture, but noted that Hippocampus kuda was among the seven species accounting for more than 99 percent of international trade in live captive-bred specimens. Many range states report that illegal trading and incidental capture in shrimp trawl fisheries remain problematic (UNEP-WCMC 2012b).
Conservation Actions Information
All Hippocampus species are listed under Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This means that countries who are signatories to CITES are subject to regulations on the export of seahorses. Countries are required to provide permits for all exports of seahorses and are meant to provide evidence that these exports are not detrimental to wild populations. However a lack of basic information on distribution, habitat and abundance means many CITES Authorities cannot assess sustainability of their seahorse exploitation and meet their obligations to the convention. The challenge is particularly large in that most seahorses entering trade are caught incidentally as bycatch and thus imposing export quotas would achieve next to nothing for wild populations. Since this listing, an average annual trade of over two million individuals of Hippocampus kuda have been reported (Evanson et al. 2011, UNEP-WCMC 2012a).
CITES has recommended a minimum size limit of 10 cm height for all seahorse specimens in trade (CITES 2004, Decision 12.54). This limit represents a compromise between the best biological information available at the time of listing and perceived socioeconomic feasibility. But we urgently need information on wild populations to assess their conservation status and take conservation action, as well as refine management recommendations. For example, evidence on variation in the spatial and temporal abundance of seahorses would enable areas of high seahorse density to be identified, as the basis for considering area restrictions on nonselective fishing gear that obtains Hippocampus species as bycatch. An understanding of the technical and logistical feasibility of returning to the sea live seahorses taken as bycatch in various types of fishing gear would provide the basis for considering the feasibility of minimum size limits and/or other output controls. Establishing a monitoring program of landings of seahorses at representative sites, taking into account different gear types and means of extraction and recording catch and effort metrics would allow us to assess population conservation status and development management recommendations for various fishery types.
There are no known species-specific conservation measures in place for Hippocampus kuda. However, there are several marine protected areas within its distribution, including the Jubail Marine Wildlife Sanctuary, where Hippocampus kuda has been recorded (Krupp and Müller 1994, Krupp and Almarri 1996).