Revista Digital Agua Simple – Agua y biodiversidad

Notas de agua - Revista digital Agua Simple

The jungle of the sea: Corals

By Itzel Bahena, Antonella Gispert and Ana Vázquez

Arrecife de coral
Coral reef. Photo by Denisse Pohls. Author/Image Bank/Conabio

Keywords: Ocean acidification, biotechnology, importance, climate change, consequences.

Corals are essential for the oceans and marine life. They are formed by small organisms called polyps. Coral reefs are one of the most diverse ecosystems on the planet, this is because coral polyps are mainly responsible for the formation of large reef colonies.

More than 25% of the ocean’s fish depend on the health of coral reefs, and it provides a protected environment for many species, it is as if it were their home (NOAA, 2019). These act as barriers to reduce the effect of tropical cyclones, storms, and erosion, they are also a great source of food and medicine.

Gran coral de estrellas. “Pólipos de Montastraea cavernosa abiertos y alimentándose durante la noche”.
Gran coral de estrellas. “Pólipos de Montastraea cavernosa abiertos y alimentándose durante la noche”.
Foto de Daniel Hernández Díaz.
Autor/Banco de imágenes/Conabio

Human activities such as ocean mining, unsustainable fishing, and fast fashion industries are some of the reasons for ocean pollution. Additionally, sunscreens cause bleaching of hard corals, even at low concentrations. These actions stress the coral and cause coral bleaching, meaning their possible death.

According to NOAA (2013), it is stipulated that coral polyps can become stressed by the increase and decrease of water temperatures, which generates a loss of algae that inhabit the polyp tissues. As a result, coral bleaching occurs. While a bleached coral is not dead, corals can survive bleaching events, they are under a lot of stress and are less resistant to hazards such as disease, which makes them more vulnerable to death. Corals can to recover from bleaching if conditions improve before they die. However, it takes many years for the ecosystem to fully recover.

Tiburón martillo y abanico de mar.
Tiburón martillo y abanico de mar.
Foto de Valeria Mas.
Autor/Banco de imágenes/Conabio

As mentioned above, finding new ways to repopulate coral reefs is crucial. Research done by Anastazia Banaszak, from UNAM’s Institute of Marine Sciences and Limnology, is using biotechnology to reproduce corals without harming the ecosystem. She developed a circular working model that starts in the sea, where she obtains the gametes (sex cells) from the corals. In order to collect the gametes without damaging the ecosystem, the colonies are covered with nets that have an inverted funnel and a collecting container at the top. As the gametes have a light buoyancy, they move from the colony easily through the net into the collecting canister. Then, she continues in the soil to fertilize the corals in the laboratory and cultivate them in special nurseries. Finally, she concludes in their natural ecosystem where she incorporates the corals into the reefs to rehabilitate the calcareous structures in which they live (Banaszak, 2013).

Coral en crecimiento y recuperación luego de pesca destructiva.
Coral en crecimiento y recuperación luego de pesca destructiva.
Foto de Saúl Meunier Blanco.
Autor/Banco de imágenes/Conabio

Although corals cover only 1% of the ocean, they are a key factor in the health of the ocean. In recent decades they have begun to be at risk of extinction due to many factors such as climate change. We must take care of our planet because if we don’t, we are putting the lives of other species in the ocean, land, and air at risk.

If coral reefs become extinct, the ocean provides less oxygen and about 25% of marine life would lose their habitat. If this amount of species were lost, it would not only affect the environment, but also the economy and people’s employment. If coral were to become extinct and many species were to die, many people would lose their source of income. It is estimated that marine tourism sites generat more than 36 billion dollars in income each year, so their loss would affect the annual income of this sector. These projects to repopulate coral reefs are essential to repopulate this ecosystem and lessen the consequences.

Morena among corals.
Morena among corals. Photo by Daniel Ernesto Pérez Galván. Author/Image Bank/Conabio
Corals, underwater guardians.
Corals, underwater guardians. Photo by Conagua (2017).

We need to create empathy for others, look beyond and take action to care for the ocean and make a real change towards climate change.

References 

Banaszak, A. (24 de noviembre, 2013). Usan biotecnología para reproducir corales y repoblar arrecifes en el caribe mexicano. Recovered from https://www.dgcs.unam.mx

Conagua, Comisión Nacional del Agua. (28 de julio, 2017). Corales, guardianes submarinos. Recovered from https://www.gob.mx/conagua/

NOAA, National Oceanic and Atmospheric Administration. (1 de junio, 2013). Anthropogenic (human) threats to corals. Recovered from https://oceanservice.noaa.gov/

NOAA, National Oceanic and Atmospheric Administration. (1 de febrero, 2019). Coral reef ecosystems. Recovered from https://www.noaa.gov/

NOAA, National Oceanic and Atmospheric Administration. (s.f.). Coral bleaching and ocean acidification are two climate-related impacts to coral reefs. How is climate change affecting coral reefs? Recovered from https://oceanacidification.noaa.gov/

NOAA, National Oceanic and Atmospheric Administration. (s.f.). How does climate change affect coral reefs? Recovered from https://oceanservice.noaa.gov/

NOAA, National Oceanic and Atmospheric Administration. (20 de junio, 2024). Skincare chemicals and coral reefs. Recovered from https://oceanservice.noaa.gov

The Reef-World Foundation. (1 de marzo, 2021). What would happen if there were no coral reefs? Recovered from https://reef-world.org