On May 25, our coastline received its seventh visit ever from the special and uncommon hippocampus hystrix, or the spiny/thorny seahorse at Chinsta Bay.
Found by EL Museum principal scientist Dr Kevin Cole, the seahorse was first spotted near East London shores since 1969.
The spiny seahorse, endemic to Indo-Pacific regions where the conditions are more tropical, has been spotted before at Haga-Haga, the EL harbour mouth, Kayser’s Beach and Orient Beach.
Significantly, the spiny seahorse has been spotted on five out of seven times, during May. The previous sighting occurred on May 8 2022.
This is because of the occurrence of more periods of warmer water incursions into our area. This is indicative of increasing ocean temperatures predicted to rise by 1-4°C by 2100, which are changing habitats and shifting the distribution of species like the spiny seahorse.
Tiny, yet armed with dermal plates, the spiny seahorse like the other 30-40 species of seahorse evolved in the oceans about 40 million years ago.
Every year about 20 million are caught to be sold as curios or used for medicinal purposes.
The spiny seahorse is vulnerable to this exploitation as seahorse trade, in collaboration with habitat destruction and practices that enable seahorse catching, has led to a 30% decrease in population growth.
Usually along our coastline, we have the hippocampus kuda, also known as pony seahorse, that is distinguished by its yellow or spotted colour.
Cole said the occurrence of the spiny seahorse may force scientists to review distribution maps for the species. He said that civil society played a role.
He said: “It is best to report the find first to the museum or the East London aquarium to make an assessment, so as not to cause harm or distress.
“Take a photograph recording the find and a wide angle shot to assist in describing the locality. If a smaller unusual dead fish specimen is found, it is best to freeze it if the museum or aquarium cannot get out to site.
“Again a good photographic record is essential with some scale like a coin or hand. Date and time are also important.
The museum will soon be looking at other developments along our coast such as dunes.
Cole explains: “The dune profile of our coast has changed over the decades with dune slumping and the associated loss of trees and plant species is noticeable in many areas along the coast. This has, in part, been attributed to an annual increase in mini-sea surge events occurring along our coastline.
“These events are driven by warmer water at sea providing energy to fuel more storms with the resultant increase in sea surges being more dramatic and destructive along our coast.”
