On Pelagic Fishes Captured in Oceanic Waters of the Northern Part of the Central Atlantic Ocean in Autumn 2019 (Results of the 44–45th Research Cruises of the R/V Akademik Nikolaj Strakhov)
摘要
Data on catches in open waters of the northern tropical part of the Central Atlantic are presented for 16 species of fish from eight families. New findings of the flying fish Cheilopogon furcatus, C. nigricans and Prognichthys occidentalis, halfbeaks Oxyporhamphus micropterus similis and Hemiramphus balao in the study area allow us to somewhat update current ideas about the distribution of these species. Our collections show a sharp dominance in numbers of four-winged flying fish (subfamily Cypselurinae) over two-winged flying fish (subfamily Exocoetinae), which dominated the study area in previous years. In addition, within the subfamily Cypselurinae, the nerito–oceanic species Hirundichthys affinis, C. nigricans and P. occidentalis, which were previously absent or rare in the study area, began to quantitatively predominate over the oceanic species H. speculiger, C. exsiliens and P. glaphyrae. We attribute all these changes to invasion of large quantities of sargasso seaweeds (genus Sargassum) in the study area, which apparently facilitated colonization of open ocean waters by previously rare species. Large quantities of sargasso weeds may also lead in the future to the increasingly frequent appearance in the open waters of the tropical Atlantic of coastal species characteristic of flotsam, such as Lobotes surinamensis, Caranx crysos and H. balao.