The photograph of a jellyfish Pelagia noctiluca with a fragment of blue plastic inside, made in the waters of Sardina del Norte in Gran Canaria by Alicia Herrera, constitutes a milestone in the study of the impact of pollution by microplastics in this species. It is the first time the ingestion of plastic by jellyfish of this type in their natural environment, in the North Atlantic, has been documented.
In 29 of the 30 jellyfish studied, some type of marine litter of anthropogenic origin was found
The research, now published in the journal Marine Pollution Bulletin, was carried out in the summer of 2019 when a bloom (large group) of Pelagia noctiluca jellyfish reached the Canary Islands. For the study, 30 specimens were collected on the beach of The pits Microplastics inside (gastrovascular cavity) and those present in the tentacles were analyzed separately.
In 29 of the 30 jellyfish studied, some type of anthropogenic marine litter was found. A large percentage were cotton fibers, but plastic fragments and remains of fishing nets were also found. 53% presented microplastics in the gastrovascular cavity, data that confirms their ingestion.
Despite its apparent fragility and its simple anatomy, jellyfish have lived on Earth for more than 500 million years and have survived major mass extinctions, so it is paradoxical that they now suffer the impact of human-generated pollution.
Mask floating in the waters of La Graciosa, taken in September 2020. / Alicia Herrera Ulibarri
This is how plastic enters the food chain
Jellyfish are an essential component of marine ecosystems, so they can be an important vector for the entry of microplastics to the marine food chain, since they are the main dams of many animals.
Jellyfish can be an important vector for the entry of microplastics into the marine food chain, since they are the main prey for many animals
The leatherback turtle (Dermochelys coriacea), for example, can eat 73% of its weight in jellyfish daily. This study, led by the Ecophysiology of Marine Organisms (EOMAR) group of the ECOAQUA University Institute of the University of Las Palmas de Gran Canaria (ULPGC), thus shows that plastics have already been incorporated into the food chain and that they represent a risk to the health not only of the jellyfish themselves, but of the higher links such as turtles, fish, birds and marine mammals.
These data confirm the critical situation regarding the contamination by plastic from the oceans. In addition, due to the current health crisis due to covid-19, the use of gloves and masks has added a new problem, since these, if not disposed of correctly, end up reaching the sea and further complicating the situation.
From the Latitud Azul association, which has also participated in the study, they warn that it is “urgent to become aware of this problem that causes thousands of deaths of marine animals a year, some of them in danger of extinction.”
Therefore, they call to make a rational use of plastic, as well as gloves and masks, and whenever possible to opt for the reusable alternatives. The loss of biodiversity and damage to ecosystems is one of the causes of the appearance of new pandemics, so, they remember, “if we do not take care of our environment, it will be difficult for us to take care of ourselves as a species.”
Jorge Rapp et al. “Microplastic ingestion in jellyfish Pelagia noctiluca (Forsskal, 1775) in the North Atlantic Ocean” Marine Pollution Bulletin
Rights: Creative Commons.