At least two species: Hippocampus guttulatus (Long-snouted seahorse) and Hippocampus hippocampus (Short-snouted seahorse)
Small marine fish that can reach 15 cm in length. Its head, with a long snout, resembles that of a horse (hence its name). They have a prehensile tail that they use to anchor themselves to plants or animals, such as corals, where they camouflage perfectly.
It is the males who get “pregnant”. They have a pouch in their abdomen, a kind of marsupium, where the females lay their eggs and where the males carry them until the birth of the babies, miniature seahorses, which emerge from the pouch already swimming!
Seahorses are particularly vulnerable species. To the unique aspects of their biology (low mobility, great dependence on habitat), we can add the fact that they live in shallow areas, near centers of human activity, where various types of pressures and threats accumulate, such as environmental degradation and their capture directed for use in traditional medicines and as aquarium fish.
In the year 2000, Ria Formosa was the area with the highest population density of these species in the world. Less than 10 years later, the population has been reduced to less than 10%, but it has shown some recovery in the meantime. Although the exact causes of this dramatic decrease are not known, it may have resulted from an overlap of factors such as underwater noise pollution, environmental degradation, fishing, among others.