I came across this word in the Post a couple of days back -'polynyas'. The article referred to it as a biological oasis in the Antartic caused by winds and other climatic conditons stripping off the ice cover over a localised region, exposing it thus, to more sunlight. The area now becomes a breeding zone for plankton and from thereon, sets off an ecologic cycle rich in all manner of aquatic life. Penguins are naturally attracted to polynyas because of the rich availability of food and penguin populations are directly linked to the presence and the productivity of these oases. I remember, the article referred to them as hotspots for penguins.
PS: I don't know if the word implies singular or plural; shall await your comments
