Dynamic climate changes have become noticeable in recent decades, especially in the vulnerable region of Western Antarctic. The relatively simple food web of this area relies on krill - Euphausia superba. Presumably as a result of climatic fluctuations, a decrease in the numbers of this crustacean has been recorded, followed by an increase in the population of the gelatinous zooplankter Salpa thompsoni.
In the inquiry herein presented, population and morphometric analyses on Salpa thompsoni have been conducted. Specimens for this research were collected from the Drake Passage, using a Bongo net in the summer season of 2010.
It has been found that the horizontal distribution of this gelatinous zooplankter was significant irregular (Kruskal-Wallis test, p<0.001). In the northern part of the investigated area both blastozooids and oozooids were recorded, which confirms the dynamical performance of this species’ development. The central part of the Drake Passage was characterized by a dominance of blastozooids, with embryos found in different stages of development. Only in the region of South Shetland Island was the Salpidae population characterized by slowed, or even stopped reproduction.
The immense reproduction efficiency observed in the Salpa thompsoni population was mostly induced by beneficial thermal conditions. These observations may suggest that ongoing environmental changes in Western Antarctic will promote expansion of this species’ population.