In Antarctica, some areas of open water along the coast are refuges from the harsh climate. Hemmed in on one side by the continental shelf and on the other side by floating sea ice, these “holes in the ice” are home to masses of phytoplankton, which form the foundation of the Antarctic marine food web. Now, Scientific American reports that researchers think iron flowing into these holes via glacial meltwater could be driving the growth of the tiny marine organisms. As climate change melts the region’s glaciers, which are rich in iron, the habitats could become even more productive. That could have important implications for the marine food web; already, animals like penguins and seals are found in high densities near these highly productive areas, the scientists say.