Life in Centro Island
The Topungus

Although the island of Centro is dominated by eggpouchers, rodent species outnumber ground birds: some species are arboreal, others are fossorial, and some are semiaquatic. However, most of them are relatively small, staying well below the threshold of megafauna (45 kg). Except for one species. The expansion of open environments on the island has led to the proliferation of a large and chubby guinea pig, humorously called Big Topungus (Caviachungus fortunei). It currently holds the title of the second-heaviest terrestrial vertebrate on the island and is also the largest guinea pig found in Antarctica. Their long incisors and robust build make them a though prey to take down, even for ovoviraptors: their main predators are in fact birds of prey, like the parstrikers, that usually prey on young and old individuals. 

The Big Topungus is typically found grazing in small herds in the vast grasslands of Centro, where it primarily feeds on forbs ang grass. Due to limited food competition, Topungus have less developed stomachs compared to their counterparts in more competitive continental environments. To maximize nutrient assimilation, they resort to coprophagy, consuming their own feces: this behavior allows them to extract as many nutrients as possible from the fibrous and leathery graminoid plants, which they are not able to digest effectively.
Despite their size, Big Topungus periodically enter a state of torpor to survive the winter period; they form large communal dens where they reside for a duration of 8 to 18 weeks. While they don't fully hibernate, their daily activity rate slows down significantly during this period. However, Topungus may occasionally wake up from their sleep to drink or defecate. 

Despite being perfectly adapted to dwell in the modern-day mosaic habitat of Centro, the ongoing aridification and the arrival of new competitors because of the current proximity of the island to the continent is slowly condemning this species towards to its extinction.
These will be the final years of glory for this species.