Some avian fauna from a worldbuilding project of mine.
The Field Bishop is a megafaunal, flightless weaver bird. Like its smaller ancestors, it uses vegetation to construct elaborate nests, keeping itself and its young safe. Its grasping feet and flexible legs have evolved for this task. The nests are typically constructed of large branches with smaller sticks woven in to fill the gaps, and look something like an amphitheatre crossed with a hedge maze.
Many other, small animals live commensaly or symbiotically within these structures. Pannagers are basal artiodactyls that walk bipedally and have convergently evolved some similarities to primates. These satyr-like beasts are gregarious and intelligent, and will lead the Bishops to rich foraging grounds in exchange for setting up home in their nests.
Grouse and gamebirds of all kinds populate the open grasslands. The Delivery Grouse is a domesticated species that is used in much the same way as a carrier pigeon. It is larger, about the size of a turkey, and can carry heavier parcels. This limits its ability to fly, but it is a swift runner with an unerring sense of direction.
Buster Grouse are much larger and far more ferocious, filling a niche similar to Phorusrhachid terror birds. Despite their menacing appearance, they usually go for prey smaller than themselves. This is thought to be to reduce competition with the larger mammalian predators of the steppes through niche partitioning.
Swarms of Pollen Peepers, small but loud alderflies that emerge en masse in the rainy season, draw a host of insectivores. The Storm Sailor is chief amongst these, covering vast distances by riding air currents, and cramming as many flies as it can into its gaping beak.
The Slot Hawker is an unusual falcon that has adapted to its craggy environment using an elongated beak that allows it to probe rock crevices for prey. It typically goes for rodents and lizards, but this buffet of insects is too tempting to miss.
This seasonal abundance also draws out typically nocturnal species like the Furbat. The rains also result in a sudden glut of fruits and seeds, with resulting population booms in granivorous species like the Ricefinch.