Cobalt-Barred Terns
Physiology
The Cobalt-Barred Tern is a medium-sized tern following a roughly standard build: It is a streamlined, small-bodied bird with a thick bill and slim, bent wings. The bird's bill is long and slightly curved, cobalt-blue in colour and with a thin black ring near the tip, while the legs are a much darker shade of grey-blue.
For most of the year the bird sports a white and black plumage pattern. Its body is primarily white, with a black hood and black wingtips as well as a thick black bar across its stubby tail. The underwings are a very pale grey colour. The Cobalt-Barred Tern takes its namesake from the striking cobalt-blue feathered bars across the shoulders of its wings, visible on both the top and bottom of the wing.
In winter, the tern loses its dark hood plumage and gains a dark patch at the throat. Their plumage grows thicker and warmer to insulate them against colder temperatures.
Behaviour
The Cobalt-Barred Tern, like most terns, is an aquatic hunter. They can typically be found hovering over the ocean around Yuriba in search of fish, which they will catch by diving headfirst into the water. They are discriminating eaters and will avoid Seraph Salmon despite having a limited resistance to the adverse effects of consuming them.
Competition during the hunt is a key facet of this tern's life. They will often fight over catches, and it is common to see two terns diving for a single fish, with the faster tern winning. The more skilled a hunter, the more likely she is to attract a partner. Cobalt-Barred Terns seldom form long-term relationships, and it is common for terns to go from lover to lover. They lay up to three eggs at a time, and though the mother may not be mated she is always helped by other terns to raise her young.
The terns nest in colonies on rocks by the water and on cliff faces. Several nests together form a colony. Terns in a colony share the catches of every hunter and provide food for single mothers. They will often mingle with nests of Amazon Gulls.
Though the birds can be seen virtually anywhere on the island and over waters throughout the Devil's Triangle they are typically only seen on foot on beaches and around their nests. They are fast fliers but are not very confident on foot.
Unlike most terns, the Cobalt-Barred Tern is not especially migratory. They live year-round in Yuriba, though many of them will winter on small islets further south, but still within the Devil's Triangle.