Population characteristics of two seahorses, Hippocampus coronatus and Hippocampus mohnikei, around seagrass beds in the southern coastal waters of Korea

Seasonal and spatial variation in the reproductive biology of the dwarf seahorse Hippocampus zosterae

“…During a yearlong survey of Hippocampus hippocampus (L. 1758) populations gravid males were documented during June through October with peak breeding during July and August, with around 70% of males carrying offspring (Curtis et al, ). Seahorse surveys for Hippocampus coronatus Temminck & Schlegel 1850 (20.5%) and Hippocampus mohnikei Bleeker 1853 (22.2%) found lower percentages of gravid males during peak breeding, with breeding seasons lasting 3–5 months (Choi et al, ). However, species like the Gulf pipefish Syngnathus scovelli (Evermann & Kendall 1896) have shown a mean ratio of 0.92 gravid to non‐gravid males across the entire year, indicating that males are almost always gravid (Masonjones et al, ).…”

“…During a yearlong survey of Hippocampus hippocampus (L. 1758) populations gravid males were documented during June through October with peak breeding during July and August, with around 70% of males carrying offspring (Curtis et al, 2017). Seahorse surveys for Hippocampus coronatus Temminck & Schlegel 1850 (20.5%) and Hippocampus mohnikei Bleeker 1853 (22.2%) found lower percentages of gravid males during peak breeding, with breeding seasons lasting 3-5 months (Choi et al, 2012).…”

New records of the Japanese seahorse Hippocampus mohnikei in Southeast Asia lead to updates in range, habitat and threats

“…In India, two additional genera of seagrass, Halophila and Thalassia , have been associated with the occurrence of H. mohnikei (Thangaraj & Lipton, ). All H. mohnikei have been reported from depths of <10 m (Thangaraj & Lipton, ; Kwak et al ., ; Otsuka et al ., ; Choi et al ., ; Zhang et al ., ). Juvenile H. mohnikei have been found in the offshore waters of Japan, and their occurrence correlated with high density of small prey items (Kanou & Kohno, ).…”

“…Previously, H. mohnikei was only observed in seagrass beds in Japan and an estuary in Vietnam (Lourie et al, ). These habitats, Zostera seagrass beds in estuary and inlet waters, are now some of the most commonly reported habitat associations in Japan (Kwak et al ., ; Otsuka et al ., ), Korea (Choi et al ., ) and China (Zhang et al ., ). In India, two additional genera of seagrass, Halophila and Thalassia , have been associated with the occurrence of H. mohnikei (Thangaraj & Lipton, ).…”

“…New records support what is known about the habitat preferences of H. mohnikei , that it lives in shallow waters, predominantly in seagrass (Lourie et al ., ) with other syngnathid species (Yagi et al ., ; Choi et al ., ; Lipton & Thangaraj, ; Zhang et al ., ), while expanding its habitat range to include mangroves, oyster beds and mussel farms. Such preferences should raise concern, as H. mohnikei lives in the same habitats as other seahorse species ( H. kuda, H. spinosissimus and H. trimaculatus ) considered Vulnerable by the IUCN Red List (IUCN, ).…”