A short lesson of antarctic toponymy
Due to the simplification of the habitats caused by the colder climate, the warmest biomes of Antarctica have drastically reduced in size and become fragmented and isolated. Here's a list of the most important relictual habitats of the continent.
VOSTOCK DEPRESSION-REFUGE
Vostock was once a subglacial lake covered by kilometers of ice but now, thanks to its size, is capable of creating a small microclimate in the surrounding environment. Temperatures are slightly higher, allowing the growth of open shrubland and localized thickets. It is an important key point for seasonal migrations of antarctic birds, which move from the lowland tundra of the Wilkes to the forests of The DD.
THE DD (DOUBLE DELTA)
The DD is the confluence of Kalt and Froid, the two main rivers of the Recovery plateau. Their deltas are so large that have fused, forming an immense contiguous forested wetland area with great biodiversity. Most woodland fauna of Polarica is restricted to this area. Ignothofago riparialae-Winterdrymetum and Sempersalicetum are the most common tree associations.
NORTHERN WEDDELL CANYONS
This is the milder antarctic ecosystem of the middle Lentocene, with winter temperatures that never go under -10 °C (50 °F), but never over 25 °C (77 °F).
River incision has caused the creation of a multitude of small canyons, hosting a highly humid climate; exposed rocks absorb the heat during the day and then release it during the night, reducing thermal shocks. This is the only location where the Macropruno caerulae-Austriquercetum association was able to persist. Periodical debris and rockfalls create narrow but long dam lakes, with shallow waters and extremely rich in fish.
BERKNER ISLAND
Berkner is an island 300 km/186 miles far from the mainland, parallel to the D.D., as large as Cyprus.
Shortly after the disappearance of the Ronne ice shelf, Berkner island sunk in the sea but then partially re-emerged because of a post-glacial rebound. Thanks to sea influences and its variable elevations, this island possesses a very high botanical biodiversity. Lowlands (90% of the island) are covered by the densest austral forest in Antarctica.
The limited space make Berkner mostly inhospitable for large vertebrates, but a handful of small species (like a small bat, an arboreal bunting and a fairly large swamp hen) were able to survive and flourish.
