The life history and ecology of seahorses in the Philippines

1 March 2016Apale, C.M. & S. Foster

Seahorses (Hippocampus spp.) are among the many genera whose life histories might render them vulnerable to overfishing or other disruptions such as habitat damage. They are generally characterized by a sparse distribution, low mobility, small home ranges, low fecundity, lengthy parental care and mate fidelity (Foster & Vincent 2004). In addition, the male seahorse, rather than the female, becomes pregnant. Indeed, curiosity about this phenomenon explains why currently more is known about reproduction than about other life-history parameters. Such life-history characteristics (notwithstanding exceptions to these generalities) may help explain why seven seahorse species in the Philippines are listed as “Vulnerable” on the 2015 IUCN Red List of Threatened Species: H. barbouri, H. comes, H. histrix, H. kelloggi, H. kuda, H. spinosissimus, and H. trimaculatus (IUCN 2015-4). The other three species are listed as „Data Deficient‟, which reflects substantial gaps in knowledge even for heavily exploited seahorses, such as the pygmy seahorses: H. bargibanti, H. denise, and H. pontohi.

This report aims to synthesize existing information on seahorse life history and ecology in the Philippines to promote management derived from the best-available biological knowledge. Understanding seahorse life history becomes particularly important now that changes in the New Fisheries Code or Republic Act 10654 Section 102 (b) mean that aquatic species listed on Convention on International Trade in Endangered Species (CITES) Appendix II will now be subject to export, unless scientific advice determines that such trade would be harmful to wild populations; all seahorse species are listed on Appendix II of CITES (see report on „Exploitation, trade, conservation and management of seahorses in the Philippines‟ for more on this). Assessing the sustainability of seahorse exports under CITES, and the fisheries that catch them, requires knowledge of their biology and ecology