site.btaAssoc. Prof. Lyubomir Kenderov: Inhabitants of the Antarctic Seabed Are an Indicator of Changes Occurring on the Icy Continent

As part of the 32nd Bulgarian Antarctic expedition to Livingston Island, hydrobiologist Assoc. Prof. Lyubomir Kenderov, PhD studied the bottom sediments that form the habitat, the water and its parameters.

“My task is to show how the organisms that inhabit the seafloor can be used as an early warning that humans are changing the living conditions in Antarctica and that measures need to be taken,” he said in an interview with BTA.

"Bottom-dwelling organisms live in conditions of many extremes. The water temperature is always close to the freezing limit. Very often these organisms are deprived of a food source because conditions are harsh," the scientist explained. According to him, organisms that inhabit the bottom of the Southern Ocean try to survive without a food source in polar night conditions that last for months.

According to Assoc. Prof. Kenderov, the primary process that creates [living] matter on planet Earth is photosynthesis. "When it is night, there are no photosynthesizing algae or planktonic bottom algae. In these extreme conditions, organisms have adapted for 20 million years or more in this unique place, they are very good indicators of the changes that we humans are inevitably inflicting on our planet," the hydrobiologist said, stressing that although there is no population in Antarctica, the global transport of pollutants with ocean currents reaches the icy continent.

"The typical marine organisms that inhabit the floor of the Southern Ocean are crustaceans called amphipods (Amphipoda). They are extremely rich in species, precisely in the conditions of these very cold waters," Kenderov said. "Usually where environmental factors are extreme, there is poor species diversity. But that is not the case here for these amphipod species. It's a paradox that is difficult to explain."

According to the scientist, amphipods are good indicators of changes in living conditions both on the seafloor and throughout the ecosystem. "They have managed to enter the ecological niches, or the “turf” of other organisms that inhabit warmer oceans. These crustaceans are well suited to serve as a monitor for these influences. Some are unknown to science, others are new species."

"The global warming in the climate of our planet is being felt in the Antarctic Peninsula, where the Bulgarian base is located on Livingston Island. This is the fastest warming place on our planet", Kenderov said and pointed out the consequences for the marine ecosystem. "In polar summer conditions, rapidly melting ice will sweeten the water. The water becomes less salty than is typical for the Southern Ocean." In this case, the hydrobiologist explained, most of the organisms will leave these habitats, and the stationary organisms will die.

Assoc. Prof. Kenderov works together with Assoc. Prof. Dr. Raina Hristova, a marine geologist from the Institute of Oceanology at the Bulgarian Academy of Sciences. Together, they are investigating Antarctic deep-sea life in a multidisciplinary project.

Assoc. Prof. Hristova studies the chemical composition, thickness and origin of the bottom sediments, which are the place where these unique organisms live, Kenderov explained. They also investigated the parameters of the aquatic environment in the area of Livingston Island - temperature, oxygen content, saturation, active water reaction, electrical conductivity and salinity. "Using the methods, the approaches, the scientific information from different geological and biological sciences, we are looking for the big picture of what is happening to Antarctica and how humans are influencing it," the hydrobiologist explained.

"Even the back side of the Moon, as they say, is more studied than the bottom of the Southern Ocean. We hope that these organisms, which are rich in diversity, will be the most appropriate group of marine organisms for monitoring environmental changes," Assoc. Prof. Lyubomir Kenderov added.

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During the 32nd Bulgarian expedition to Antarctica, which started on November 8, 2023, the Bulgarian News Agency (BTA) is publishing interviews with Antarctic researchers. The Bulgaria-Antarctica BTA's Log again provides coverage of the voyage of the Sv. Sv. Kiril i Metodii to Antarctica and back and its stay there, as it did during the 31st expedition between December 27, 2022 and May 2, 2023. Back then, only BTA had a correspondent, Daily News Editor Konstantin Karagyozov, who covered the 127-day expedition with text, video and photos during the entire voyage (including across the Atlantic in both directions) and throughout the stay in Antarctica. In June 2023, BTA published in Bulgarian and in English an issue of its LIK magazine "To Antarctica and Back under the Bulgarian Flag" dedicated to the historic expedition.

Again, all of BTA's information on the Bulgarian scientific research in Antarctica and the support provided by the Bulgarian naval research vessel, as well as on the other activities at the Bulgarian Antarctic Base, will be available to all media outlets in Bulgarian and in English on BTA's website in the Bulgaria - Antarctica: BTA's Log section.

BTA has a National Press Club on board the ship and is planning to open a National Press Club at the Bulgarian Antarctic Base on Livingston Island.