Have you ever seen a ray in the sea, or perhaps even snorkeled alongside one? Most of us probably only know these animals from pictures or aquariums.
While searching for growing sharks, researchers recently investigated the mangrove lagoons off San Cristóbal. They noticed that there are also a large number of young rays in these lagoons. Apparently, the two cartilaginous fish share their nursery. So the researchers collected tissue samples not only from the young sharks, but also from spotted eagle rays and golden rays. When analyzing this data, they realized how little we know about these unusual inhabitants of the Galápagos Marine Reserve.
We don't know enough about rays
In particular, there is a lack of knowledge about their way of life, e.g., the area in which the rays move or whether they migrate and, if so, where to. There is also no genetic material from these animals that would allow comparisons between the individual ray species in the Galápagos Marine Protected Area. As many ray species are classified as endangered by the International Union for Conservation of Nature (IUCN), it is important to collect comprehensive data on the relationships, distribution, and lifestyle of these cartilaginous fish. This is the only way to develop projects that meet the needs of the rays and enable their long-term protection.
Unfortunately, rays are still caught by fishing fleets in their thousands or end up as bycatch in trawl nets. Unsustainable fishing methods in particular mean that the animals in the Galápagos Marine Reserve are also threatened. In addition, rays feed near the sea surface, filtering plankton and crustaceans from the water in the same way as whale sharks. Unfortunately, this often results in serious injuries from ship propellers.
Gathering Information
For this reason, researchers now want to collect comprehensive data in three mangrove lagoons in the south of the island and at a gathering point for manta rays near the village of Puerto Villamil on Isabela. They hope to gain new insights into the genetic composition, population sizes, and behavior of the various ray species. In addition, individual characteristics of individual rays will be recorded so that they can be recognized later.
Of particular interest are the golden stingrays (Rhinoptera steindacheneri). They are considered near threatened, although their exact population sizes in the Galápagos are unknown. The same applies to the spotted eagle ray (Aetobatus occelatus). It is classified as endangered by the IUCN. The habitat and nurseries of these two species of ray will be studied intensively in order to estimate their population sizes and provide the IUCN with up-to-date figures.
The large manta ray (Mobula birostris) is also considered endangered. Genetic data suggests that the animals off the Galápagos Islands may even be a separate species. These fish will also be tagged with transmitters to find out to what extent they encounter manta rays from other habitats. This will also make it possible to track where the animals spend the rest of the year.
Please help us learn more about these interesting sea creatures and protect them for the long term!