Featured iSeahorse observation - Hippocampus subelongatus, a Data Deficient species

By Kately Nikiforuk

Western Australian seahorse ( H. subelongatus ) by Maarten de Brauwer.

Western Australian seahorse (H. subelongatus) by Maarten de Brauwer.

Our latest newsmaker is Hippocampus subelongatus, a Data Deficient species rarely observed on iSeahorse! This observation is courtesy of Maarten de Brauwer, who is one of our two National Seahorse Experts for Australia. Maarten spied this fine fish in Western Australia, the sole patch of the globe this species is known to inhabit. Fittingly, they are commonly known as the Western Australian seahorse, but they are also referred to as the tiger snout seahorse - not to be confused with the tiger tail seahorse, H. comes!

Their exact distribution along the coast of Western Australian is hazy, but researchers have encountered them from the Abrolhos Islands to Rockingham. They can even be found swimming the saltier parts of the Swan River in Perth, indicating a relatively high tolerance for low salinity. They often hang around sponges, seagrasses and sea squirts, and move to deeper waters in the winter.

Maarten’s picture is only the 9th Western Australian seahorse to be catalogued on iSeahorse. Compare that to over 300 iSeahorse observations of the big-belly seahorse (H. abdominalis), another Australian species that we highlighted last time. But encountering rare creatures doesn’t seem like a rare occurrence for Maarten - he has a rad blog called Critter Research that’s definitely worth scrolling through!

In addition to H. subelongatus, there are still 17 Hippocampus species listed as Data Deficient (DD) on the IUCN Red List, plus 2 newly discovered seahorses that are yet to be evaluated. While we appreciate all of the observations you post to iSeahorse, it is particularly exciting to see DD species, as each post gets us one fin-stroke closer to understanding their current conservation status.

And it certainly feels like we’re getting closer - Maarten isn’t the only one to have seen H. subelongatus recently. At the end of 2018, a Western Australian seahorse was crowned with the Guylian Seahorses of the World Hugygot Prize!

More information

Pollom, R. 2017. Hippocampus subelongatus. The IUCN Red List of Threatened Species 2017: e.T40773A54906710. http://dx.doi.org/10.2305/IUCN.UK.2017-3.RLTS.T40773A54906710.en. Downloaded on 10 January 2019.