The genus is also widespread in the Alps. The name Saxifraga is derived from Latin and literally means ‘stone breaker’. This might seem to reflect these plants’ ability to live in mountain areas, however the name comes from the fact that some species of Saxifraga are used to treat kidney stones!

The mountain avens (Dryas octopetala) lives both in the Arctic and the Alps. This prostrate shrub grows in rocky areas where it finds stable debris, thus ‘colonising’ new environments and reinforcing the soil with its dense network of roots.
The numerous samples of Dryas pollen, recovered from the ice cores used in paleoclimatic, studies have given their name to the periods when glacial conditions returned between 14,000 and 12,000 thousand years ago, during the last deglaciation. It belongs to the rosaceae family, although its flowers have eight rather than five petals (hence its name).

The polar willow (Salix polaris)  is common throughout the High Arctic tundra and in the colder mountainous areas of the boreal forest belt. A prostrate plant with very small leaves and flowers, this dwarf shrub has developed a survival strategy that involves extending its branches into the surface soil. Fossil pollen finds, made in southern Europe, confirm the timing and extent of the ice ages.

Most birds in the Arctic are seabirds or shorebirds (terns, gulls, or puffins) that prey on fish or invertebrates. Many are drawn to wetlands, such as the various species of anatidae and waders.

Birds adopt a range of strategies against predators such as foxes: one is camouflage, as in the case of the purple sandpiper (Calidris maritima).

Another strategy is to choose isolated nesting sites or to find strength in numbers as part of a community where the chicks are protected, as in the case of the barnacle goose.

Many of these birds form stable mating pairs, both members performing incubating duties: the demands of reproduction are just too great and require the utmost care from both parents, as in the case of human beings!

But the tundra is also home to sedentary animals. These include birds such as the beautiful rock ptarmigan, as well as foxes and reindeer.
Sedentary animals have developed wintertime adaptation strategies: changing coat (thick and white in winter, brown in summer), a stockier body, or even feathered legs in the case of the ptarmigan!
The Svalbard reindeer has a squatter body and shorter legs to avoid heat loss.

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AGAMI, Risto, Vittorio Tulli | Rights reserved | Adobe Stock

Left to right: Rock ptarmigan; Arctic fox; Svalbard reindeer in summer coat

The fox builds up food reserves during the winter, hiding eggs and prey under the frozen ground that can later be recovered from under the snow.
Like all predators, however, the fox plays an essential role in maintaining biodiversity: without it, some populations would grow too much compared to others, resulting in an unbalanced ecosystem.

The polar bear lives in these areas but only crosses the tundra when changing location. The animal hunts on the sea ice, feeding mainly off seal, even if, due to climate change, it is changing its feeding habits: in summer 2022, polar bears have been observed hunting reindeer, which in the past was thought totally an unusual behaviour.

At the same time, however, rising temperatures lead to a thicker ‘active layer’ in summer, in other words the portion of the soil above the permafrost layer thawing in summer-early autumn, only to refreeze roughly between October and June. This in turn leads to increased activity by decomposer bacteria.  

The resulting intensification of microbial respiration transforms the tundra, potentially making it a CO₂ source rather than a carbon sink, thus further increasing the greenhouse effect and global warming.

It is vital to discover whether the tundra will continue to be a carbon sink or become a CO₂ source. Researchers all over the Arctic are measuring the CO₂ fluxes from the tundra, including a group of Italian researchers at the CNR Arctic base on Svalbard.

Plant or animal invasive species from warmer regions, brought here by migrating birds or human beings, could survive with rising temperatures.
Early onset of the growing season has an impact on the quality of the diet of herbivorous migrating birds, such as geese, feeding on fresh grass at the beginning of the summer season.

Furthermore, snow melted by unexpected temperature rises could refreeze to form a glassy barrier and prevent reindeer from reaching the lichens they feed on in wintertime.

Finally, rising sea levels could causes the disappearance of the intertidal zone providing migratory birds with one of their breeding grounds.

Careful studies are required to fully grasp the importance and fragility of this splendid ecosystem, its role in regulating the climate and biodiversity, and the need to mitigate climate change to avoid losing its enormous wealth.