Whilst the spotlight often shines on classical marine megafauna such as turtles, whale sharks, manta rays and dolphins, the true stars of the ocean can be better seen through a microscope. Present in every ocean and no bigger than a grain of rice, plankton are the life force of the ocean.
The word “plankton” derives from the Greek word for “drifter” or “wanderer.” Any organism that is carried by the tide and currents and is not strong enough to maintain itself against these forces is considered a plankton. Their presence is constantly directed by these ocean movements as well as wind-driven surface swells; propelling them up and down the water column on a daily basis, creating aggregation zones that larger animals depend on for food. Some plankton drift in this manner throughout their entire life cycle, whilst others are only classified as plankton when they are young, growing out of their planktonic stage once they develop in size and are able to dictate their own movements against currents.
Of these microscopic organisms there are two types; Phytoplankton and Zooplankton. Phytoplankton are microscopic plants, forming the basis of all marine food webs. Like plants on land, phytoplankton convert the sun's rays into chemical energy to support them, taking in carbon dioxide and producing oxygen in the process. Zooplankton are next in line, feeding on phytoplankton. Their collection ranges greatly in size and form, with most being microscopic in size. Occasionally, some can be seen with the naked eye, including larger species like some crustaceans and jellyfish.
Both types of plankton play a fundamental role in sustaining balance in the marine ecosystem with extensive contributions towards terrestrial environments functioning. Phytoplankton are considered the lungs of the ocean and equate to the same role and importance as our terrestrial oxygen powerhouse; rainforests. An estimated 50 percent of the oxygen in our atmosphere is produced by phytoplankton. Simultaneously, they are extremely important to the Earth's carbon cycle by helping to process and store carbon. In addition to oxygen production, phytoplankton are responsible for most of the transfer of carbon dioxide from the atmosphere to the ocean, acting as a carbon ‘sink’, which in turn mitigates the negative impacts of atmospheric carbon and its association with global climate change. Therefore, the tiniest of living organisms exert an outsized influence on the planet.
In the Maldives, a high concentration of plankton-dependent megafauna can be found, including the world's biggest fish - the whale shark - as well as other gentle giants such as manta rays. By the nature of Maldives equatorially orientated situation, high sunlight intensity and dramatic underwater geography, the world’s flattest country hosts iconic and unique phenomena relating to seasonal changes and mass aggregations events of plankton and associated planktivorous megafauna. At Intercontinental Maldives Maamunagau Resort, our lagoon becomes a hotspot for seasonal visits of feeding manta rays between the months of December to April. When the north easterly winds blow during this time, the unique shape and position of the lagoon within Raa Atoll creates a large catchment zone for plankton, leading to an explosion of rich and diverse visiting marine life.
Join us this world ocean day alongside our resident team of marine biologists and the Manta Trust team, who are dedicated to studying and researching the population dynamics of manta rays and their food source. Dive further into the world of plankton to discover more about how our future ocean and climate depend on it.
