What is the Sargasso Sea and what ecological role does it have?

The Sargasso Sea is an area located in the north atlantic ocean characterized by the abundant presence of algae of the genus Sargassum and because it is a generally quiet area, with few currents and little wind. Due to these characteristics, the first navigators had difficulties to navigate and this area was associated with mysterious stories, including part of the famous Bermuda triangle.

During the Portuguese expeditions around the Azores at the beginning of the 15th century, an area of ​​the Atlantic Ocean was discovered in which large populations of macroalgae abounded floating in the water. These algae were called Sargaco, where the current name of the sea derives from. The first to completely cross the Sargasso Sea were the expeditions of Christopher Columbus in 1492.

However, it is believed that the Sargasso Sea could have been known for several centuries since there are allusions to this area of ​​the ocean in literature from earlier times. For example, a poem by Rufus Festus Avienus written in the 4th century AD describes an area of ​​the Atlantic covered with algae that could be the current Sargasso Sea.

Location and characteristics

The Sargasso Sea is an area of ​​the North Atlantic Ocean bounded on the west by the Gulf Streamcoming from the Gulf of Mexico, to the north by the North Atlantic Currenteast by Canary Islands Current and south by North Equatorial Current. More specifically, it is located between the 70º and 40º W meridians and the 25º to 35º N parallels.twoIt is variable.

This combination of ocean currents together form what is known as Gyre of the North Atlantic and leave in the center an area of ​​calm waters with few currents. This causes warmer, less dense waters to rise to the surface in a slow, circular clockwise motion over deeper, cooler, denser waters. This difference in density creates a fairly defined stratification of the waters that will play a very important role in the development of marine life in this area.

The ecological role of the Sargasso Sea

It could be thought that the Sargasso Sea harbors little life, lacking currents that bring the necessary nutrients and being on a deep ocean floor. However, it is actually a area full of lifepresumably thanks to the nutrients coming from water currents of lower layers.

In the upper layers where the water is relatively warm and sunlight reaches, algae and phytoplankton (vegetable plankton) have the optimal conditions to live and grow in large numbers. The algae of the genus stand out Sargassum that grow forming extensive "forests" floating in the upper layers close to the surface. These sargassum forests attract numerous species of marine animals for different reasons, creating a area of ​​high ecological importance.

A 2004 expedition led by John Craig Venter, the first of several expeditions, identified more than 1,800 new species in microplankton from samples taken from the Sargasso Sea, which may provide insight into the great existing biodiversity.

In addition to the great biodiversity, the Sargasso Sea is fundamental in the life cycle of the american eel and the european eel. Both species migrate to the Sargasso Sea to spawn. The young grow here and migrate to the coasts of Europe and the United States, returning to the Sargasso Sea as adults to spawn. It is also believed that loggerhead sea turtle hatchlings (caretta caretta) use the currents of the Gulf of Mexico to reach the Sargasso Sea where they grow until they are mature hidden in the kelp forests where they have food and can hide from predators.

Sargasso Sea Pollution

Similar to what happens in what is known as the Plastic Island of the Pacific, the concentric currents of the North Atlantic Gyre drag towards its interior rubbish and waste from human activity that are concentrated in the Sargasso Sea. Non-biodegradable waste, mainly plastic, remains in suspension in this vortex, posing a serious threat to its biodiversity.

Currently there are several organizations and institutions, both governmental and NGOs, whose objective is the environmental protection of the Sargasso Sea. One of the most prominent is the Sargasso Sea Commissioncreated on March 11, 2014 through the Hamilton Declaration on Collaboration for the Conservation of the Sargasso Seadeclaration signed by the governments of the Azores Islands, Bermuda, Monaco, the United Kingdom and the United States.

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