Planetlight

Though it can be easy to forget, Serina - even inhabited as it is with life - is a moon and not a planet. It revolves around a far larger celestial body: a bluish colored gas giant which appears as a large "moon" in its own sky, several times larger than our own appears from Earth and easily spotted either day or night, but only from one side of the moon, which is tidally locked to its planet. In the sky on the side which faces the planet said planet is prominent and unmistakable - and as would be expected, its presence has a very dramatic effect on the world of birds. So large and bright is the light blue celestial body that even during the night on this side of the moon, when the skies are clear and free of clouds, it illuminates the environment as if a blue floodlight has been cast over the land. The light reflected by the gas giant from the sun can then be sufficiently bright that diurnal birds continue to call and feed and even the dead of night is bathed in a state of blue twilight, where the normal partitions of day and night life are broken and nocturnal and diurnal animals come out together.. Conversely, as the planet is hidden from view on the other side of the moon, the nights there - particularly under cloud cover - can be pitch black, and day and night life are much more separate.

Serina orbits around its planet in an elliptical manner, and thus is at times nearer and further from the gas giant's gravitational pull, which is the source of Serina's tides. Oceanic tides are generally stronger than those of Earth, and richly diverse floodplain ecosystems occur abundantly along the sea coasts as a result of a daily reliable surge of water inland.

above: a dolfinch glides just beneath the surface of the sea, under the soft light of the gas giant.