Ovoviraptors
Winners of a lost battle

In the first-ever drainage of the Weddell Sea in the Biancocene, the insular fauna of Centro Island finally encountered the continental fauna. However, this event was far from peaceful: the endemic biota of the island was ill-prepared to face the invasion of much more competitive species from the mainland. Large animals were the first to succumb, while the ranges of small species became fragmented. But as always, there were exceptions: sometimes, certain small and fortunate species were so uniquely adapted that their traits proved perfect even in a continental environment.

This was the case for ovoviraptors, a group of eggpouchers with an ecological niche comparable to terror birds or herdstalkers. While larger species rapidly went extinct due to their inability to compete against continental predators, the smaller species were already adapted to coexist with larger carnivores and could also feed on small rodents, their primary food source. These small survivors, about the size of a turkey, not only managed to survive the mainland invasion but also expanded their range across the continent.

While diablovoviraptors are limited to the coldvanna and the northernmost parts of the trample steppe, another species of ovoviraptor is much more widespread but has maintained a small size, similar to its ancestors. Known as the barren-ground ovoviraptor (Miniraptor nullus), it can be found in open areas ranging from the coldvanna and trample steppe to the most inhospitable regions of the moss tundra. Due to its small size, this predator typically feeds on small vertebrates no larger than itself. A small population can even be found on Drop Islands, where it mostly feeds on sea carrion and the eggs/chicks of breeding sea birds.
Unique among its relatives, the barren-ground ovoviraptor undergoes seasonal feather molt. During summer, it possesses a brown coat to blend with the soil, while its plumage turns white in the harsher seasons to ambush prey in the snow. The molt's timing does not depend from the atmospheric temperature, but from the change of the circadian rhythm* (nights are longer in winter, days are longer in summer), an adaptation analogous to other polar animals, like the ptarmigan. Compared to its larger relative, the barren-ground ovoviraptor possesses a shorter yet more robust beak, better suited for rapid chomps rather than pecking its prey. This adaptation likely aids in catching rodents and birds hidden inside burrows.