site.btaDay 85: Hydrobiologist Vessela Evtimova: Copepods Boeckella poppei Reign Over Livingston Island's Ponds

Copepods of the Boeckella poppei genus reign over small ponds and puddles on Livingston Island, said Chief Assistant Professor Vessela Evtimova, hydrobiologist at the Institute of Biodiversity and Ecosystem Research at the Bulgarian Academy of Sciences (BAS) and participant in the 31st Bulgarian Antarctic expedition.

The two-year international project, which Evtimova leads, investigates the functioning and adaptations of freshwater ecosystems and the organisms that occur in them under extreme polar conditions.

"Looking down, we see these red dots everywhere. They've evolved and developed in such a way that this kind of adaptation helps them dominate - they're the kings in these little puddles, these little ponds," noted Assist. Prof. Dr Evtimova, specifying that a dominant species is the one that occurs most often in a given habitat.

The representatives of the species Boeckella poppei survive as long as the lake exists. They breed in it by producing eggs. The data from Dr Evtimova's research shows that the concentration of the characteristic red pigment of these animals is highest in their eggs. The mothers extract the pigment while feeding and accumulate it in their eggs. This is a defence and survival mechanism for these crabs and their offspring, explains the scientist.

The lifespan of Boeckella poppei copepods is determined by how long the pond they are in will last. Usually, it lasts for a few months. "When conditions start becoming unfavourable and the water starts to disappear, they develop another type of egg that can survive during the Antarctic winter buried under ice and snow. The next year, when the lake is refilled with water and conditions are favourable again, this other type of eggs re-develop, continuing the life cycle of the species," added Assist. Prof. Dr Evtimova.

One of the mechanisms by which representatives of Boeckella poppei genus can be spread and transported from one place to another is by birds that land around the island's various ponds, she explained.

BTA's Daily News editor Konstantin Karagyozov is the only member of the media who is travelling on board the ship to Livingston Island and back and covered the Bulgarian expedition throughout its stay in Antarctica.

All media outlets can use the Bulgaria-Antarctica BTA's Log for free.