First featured iSeahorse sighting of 2017 - a thorny seahorse

By Kately Nikiforuk

The first showcased iSeahorse sighting of 2017 is of a thorny seahorse, Hippocampus histrix. It was found within the boundary of Mafia Island Marine Park, a region in Tanzania consisting of island, coastal and ocean ecosystems that are internationally acclaimed for their biodiversity.

Globally, the thorny seahorse population is suspected to have declined at least 30% over the last 10-15 years, and this trend is predicted to continue. In 2002, this species was listed as Data Deficient on the IUCN Red List, but after conducting surveys and analyzing international trade data, they were classified as Vulnerable in 2012. This highlights the importance of research for conservation - to formulate a gameplan for protecting H. histrix, we need to understand their population dynamics and the threats they face.

Mafia Island Marine Park encompasses six islands and ten villages, and its reefs harbour hundreds of distinct fish, invertebrate and algal species. The human inhabitants of the Mafia Island community are highly dependent on the natural resources found within the park. While commercial fishing and coral mining are forbidden, the land is sustainably used by local fishermen, and sightseers are encouraged to explore the world-renowned diving sites.

Not only is Mafia Island Marine Park important in that it protects local biodiversity, including the dugong, the hawksbill sea turtle, the green sea turtle, the writhing gecko and the Seychelles flying fox, but it also increases biodiversity in other regions of the ocean. Many larvae start their lives within the park before being swept along by the North East African Current, dispersing as far as the Red Sea.

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