Page 29 - living-ice

Hidden biodiversity
in the ice
Microscopic algae, animals and bacteria hibernate inside the ice during the winter darkness, waiting for the light to return. Within about two weeks of the onset of spring, they come to life again and start to reproduce. The water underneath the ice provides the ice algae with nutrients, while these microalgae in turn are food for small animals such as roundworms, ciliates and wheel animals.
Where herbivores reproduce, carnivores can also thrive. Sympagohydra tuuli is an example of a carnivore living inside sea ice. This half a millimeter-long jelly sh is one of many new discoveries that Arctic SIZE researchers have added to the growing inventory of species that live in sea ice. This list now includes approximately 6500 bacteria, over 1000 algae and 50 animal species. All these species live together in a maze of channels, forming a microscopic network.
Larger animals also constitute an important part of the sea ice ecosystem. Various crustaceans and polar cod form a major part of the diet of seabirds and seals that migrate to ice-covered areas in spring when the algal bloom provides abundant food. The diversity of organisms feeding in the seasonal ice zone also attracts polar bears in search of food.
PHOTO: Rolf Gradinger, UiT; Shawn Harper, University of Alaska Fairbanks; Peter leopold, Norsk Polarinstitutt; Bodil Bluhm, UiT; Kyle Dilliplaine, University of Alaska Fairbanks; Julia Ehrlich, AWI; Michel Poulin, Canadian Museum of Nature