It can grow to a maximum of 16 centimeters, change color depending on mood and habitat, and, like all seahorses, the White’s seahorse male gestates its young. But this tiny snouted fish is under threat. White’s seahorse, also called the Sydney seahorse, is native to the Pacific waters off Australia’s east coast. In recent years, populations have decreased drastically. It and the South African Knysna seahorse are the only two out of around 50 seahorse species to be listed as endangered.
Seahorses are found in tropical and temperate coastal water worldwide, but are most abundant around Australia, China and the Philippines. Trade in the tiny creatures is strictly regulated because of their use in traditional medicine, aquariums and their sale as dried curios. But because they are poor swimmers and cannot easily move elsewhere, habitat loss is a particular threat for these curious animals. Where corals aren’t available, scientists found seahorses taking up residence in fishing nets and old crab traps abandoned at the bottom of the ocean. This inspired the Sydney team to increase available habitat in the famous Australian harbor by building cages of net and steel. Over time, algae, sponges and corals colonize the structures, creating a safe, welcoming environment for the seahorses, say the researchers. The hotel frame will eventually corrode, leaving behind the coral mounds that have grown around them.
With seahorses everywhere facing the loss of their coral reef homes, similar projects have sprung up in places like Greece and South Africa, home to the world’s most endangered seahorse, the Knysna seahorse. In the South African case, seahorses have bedded down in “Reno mattresses” — wire cages filled with rocks — that were used to build a new marina. Researchers from NGO Knysna Basin Project found the structures acted as a refuge for the animals.
Source: Deutsche Welle
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