Search Results (7)

The Ross Sea region Marine Protected Area (RSR MPA) is one of the most productive regions in the Southern Ocean. Mesozooplankton intermediates the primary product to the higher predators, such as penguins and seals, in this ecosystem. In this study, the mesozooplankton community structure and spatial pattern in the RSR MPA in January were investigated by using 505 μm-mesh-size bongo net samples. As a result, 37 mesozooplankton taxa with a total mean abundance of 35.26 ind./m³, ranging from 2.94 to 139.17 ind./m³, were confirmed. Of the 37 taxa, 7 occupied almost 84% of the total abundance, with copepods being the main dominant taxa. As shown by our hierarchical analysis, the mesozooplankton community was divided into four groups, each associated with a specific geographical distribution. Group A was composed of stations around Terra Nova Bay and showed relatively low abundance. Group B included stations around the continental slope region. Group D was composed of the Ross Sea continental shelf stations, while group C consisted of stations geographically located between those of groups B and D. These four groups were influenced by various environmental factors, such as water temperature, salinity, and nutrients. In summary, the mesozooplankton community can be separated according to geographical pattern. This pattern is related to several environmental factors. Full article

The Southern Ocean plays a vital role in the global climate system and the life cycle of high-latitude marine life. Phytoplankton is an important source of primary productivity in this ecosystem. Its future changes could affect Southern Ocean geochemistry, carbon export, and higher trophic organisms. To better protect Antarctica, three different marine protected areas (MPA) have been established in the Ross Sea region. Because time-continuous and regionally complete data are difficult to obtain in this region, we obtained data from ocean model outputs to understand the spatiotemporal variability of phytoplankton biomass in this region. This study explored the correlation between phytoplankton biomass and key environmental factors. Phytoplankton biomass peaks in February as temperatures rise and sea ice melts. Correlations also vary between different protected areas. The correlation between biomass, nitrate, and salinity in the Krill Research Zone (KRZ) area was significantly different from other protected areas. In addition, in the context of global warming, Antarctica lacks temperature perception. The model results show a downward trend in temperature and an increase in sea ice coverage in the western Ross Sea that other studies have also pointed to. How phytoplankton biomass will change in protected areas in the future is a question worth considering. Finally, the study simply simulates future regional trends by comparing the biomass distribution in hot years to average years. This will increase our knowledge of the polar system. Full article

The human-induced disturbances in Antarctica have caused changes in the structure and function of ecosystems. The Cape Hallett station was established in 1957 and abandoned in 1973. The station was built inside a penguin colony, and during its operation, many penguins were deported. Herein, we compared the number of breeding pairs across different time periods after station decommission and environmental remediation. The station occupied 4.77 ha within the Adélie penguin breeding area, and 349 nests were identified inside the station border in 1960. In 1983, the station’s territory decreased to 4.2 ha; meanwhile, 1683 breeding pairs were counted in the old station area. The past station area re-inhabited by Adélie penguins had 6175 nests in 2019. We assumed that recolonization might be particularly related to artificial mounds. The results of the present study confirm the recolonization of Adélie penguins at Cape Hallett for the first time, with visual analysis of spatial-temporal changes. Additionally, we suggest that reconstruction of the artificial or enhanced habitat may be required for successful restoration. Furthermore, continuous species monitoring with specific notes are needed with management interventions to protect Antarctic ecosystems, as well as the Ross Sea region MPA. Full article

Due to the remarkable ecological value of the Ross Sea, the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) adopted a large-scale Ross Sea region marine protected area (RSRMPA) in 2016. Since then, many CCAMLR Members have conducted research and monitoring in the region. In 2021, the U.S. Ross Sea science community convened a workshop to collate, synthesize, and coordinate U.S. research and monitoring in the RSRMPA. Here we present workshop results, including an extensive synthesis of the peer-reviewed literature related to the region during the period 2010–early 2021. From the synthesis, several things stand out. First, the quantity and breadth of U.S. Ross Sea research compares to a National Science Foundation Long Term Ecological Research project, especially involving McMurdo Sound. These studies are foundational in assessing effectiveness of the RSRMPA. Second, climate change and fishing remain the two factors most critical to changing ecosystem structure and function in the region. Third, studies that integrate ecological processes with physical oceanographic change continue to be needed, especially in a directed and coordinated research program, in order to effectively separate climate from fishing to explain trends among designated indicator species. Full article

We report for the first time the occurrence of at least two species of the phylum Gnathostomulida in the Southern Ocean, along the shores of the Ross Sea in Antarctica. At least one species for each of the orders of the phylum (Filospermoidea and Bursovaginoidea) was found using both morphological inspection and DNA metabarcoding of the shallow marine sediments collected with a Van Veen grab or by scuba diving in the area facing the Italian research station “Mario Zucchelli”. Full article

Marine biogenic skeletal production is the prevalent source of Ca-carbonate in today’s Antarctic seas. Most information, however, derives from the post-mortem legacy of calcifying organisms. Prior imagery and evaluation of Antarctic habitats hosting calcifying benthic organisms are poorly present in the literature, therefore, a Remotely Operated Vehicle survey was carried out in the Ross Sea region Marine Protected Area during the 2013–2014 austral summer. Two video surveys of the seafloor were conducted along transects between 30 and 120 m (Adelie Cove) and 230 and 260 m (Terra Nova Bay “Canyon”), respectively. We quantified the relative abundance of calcifiers vs. non-calcifiers in the macro- and mega-epibenthos. Furthermore, we considered the typology of the carbonate polymorphs represented by the skeletonized organisms. The combined evidence from the two sites reveals the widespread existence of carbonate-mixed factories in the area, with an overwhelming abundance of both low-Mg and (especially) high-Mg calcite calcifiers. Echinoids, serpulids, bryozoans, pectinid bivalves and octocorals prove to be the most abundant animal producers in terms of abundance. The shallower Adelie Cove site also showed evidence of seabed coverage by coralline algae. Our results will help in refining paleoenvironmental analyses since many of the megabenthic calcifiers occur in the Quaternary record of Antarctica. We set a baseline to monitor the future response of these polar biota in a rapidly changing ocean. Full article