Lakes, rivers and marine waters are probably of good or very good ecological status. Habitat degradation is not regarded as a major issue in Greenland. However, climate driven changes in physical properties might alter the biological balance and regional biodiversity. For instance, northward retreatment of the sea ice edge has been linked to an increase in the distribution of kelp beds and increase in the seasonal productivity of seaweeds along the Greenland West coast (Krause-Jensen et al., Wild species, and to some degree pollution and invasive species, may threaten the present good status. In addition, copepod droppings constitute a food resource for bottom-living animals as they sink to the seafloor.