Tiny plants called phytoplankton are found floating in the water or frozen in sea ice. They get eaten by herbivores such as krill and zooplankton. Carnivores in the Ross Sea include whales, penguins and seals, as well as less well known carnivores like the giant squid or the 2 metre long toothfish.
The scientists will try to understand how the food web in the Ross Sea works. The arrows in the diagram go from prey species these get eaten to predators the hunters. This work will help to show how fishing affects other animals in the Ross Sea and try to answer two important questions:. Phytoplankton are microscopic but occur in large numbers in the water and are also attached to sea ice. Zooplankton that eat the phytoplankton vary in size from microscopic to those we can see with the naked eye such as krill.
Larger zooplankton eat smaller zooplankton, which eat even smaller zooplankton, with sometimes up to 4 links in the food web between the phytoplankton and krill in Antarctic waters.
Larger zooplankton are then eaten by fish like the Antarctic silverfish. See the video The bottom of the food chain for more information.
Benthic food webs Animals that live on the seabed depend on food produced in the surface waters where there is enough light to support photosynthesis by phytoplankton. In other seas, much of this plankton is eaten by zooplankton or broken down by bacteria in mid water. The Ross Sea is remarkable in that most of the production by phytoplankton sinks directly onto the seabed, supporting rich communities of larger benthic animals, such as sponges and sea cucumbers that filter plankton from the water or from the seabed.
Gulf Publishing Co, Houston, pp — Polar Biol — In: Fishes of the open ocean. Shirsov Institute of Oceanography. Hubold G The early life-history of the high-Antarctic silverfish Pleuragramma antarcticum. Springer, Berlin, pp — Schnack SB Feeding of Euphausia superba and copepod species in response to varying concentrations of phytoplankton. Williams R Trophic relationships between pelagic fishes and euphausiids in Antarctic waters.
Download references. You can also search for this author in PubMed Google Scholar. Reprints and Permissions. Hubold, G. Stomach contents of the Antarctic Silverfish Pleuragramma antarcticum from the southern and eastern Weddell Sea Antarctica. Polar Biol 5, 43—48 Overcast day in the Western Antarctic peninsula with a Chinstrap penguin. Generally, when discussing ice in the Antarctic, we are talking about 3 types of ice: sea ice, ice shelves, and the ice sheet land ice. We know that the Arctic has decreasing ice cover.
The Antarctic, on the other hand, sends a much more mixed message. SAM is a belt of westerly winds that move around Antarctica that can vary on time-scales of weeks to years.
This variation influences the strength and position of cold fronts. ENSO is variation in the winds and sea surface temperature over the tropical eastern Pacific Ocean, which in turn can influence precipitation and ocean circulation around Antarctica Carleton Increased melting ice at the edges of the continent released large amounts of fresh water and ice algae algae found within sea ice into the upper layer of the Southern Ocean. This is a huge flush of nutrients into this region of the ocean as the nutrients that were trapped in the sea ice now enter the ocean that results in algal blooms and provides food for krill.
Krill are a major food source for penguins, whales, seals, fish and seabirds. Despite the increased biomass algal blooms, reduced sea ice diminishes the available habitat to krill, which use sea ice in a crucial phase of their reproductive cycle. Antarctic silverfish Pleuragramma antarcticum. Source: Science Learning. The Antarctic silverfish is a species that eats krill and is the prey of many larger species in the Antarctic food web such as seals, baleen whales e.
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