Breeding starts in May in the south of the range, and in the north, timing depends on when spring thaw occurs. Several pairs may breed semi-colonially, especially when there are few tracts of suitable water within reach of their feeding areas. Thus they are tolerant of other pairs close by and only defend the area immediately surrounding the nest. 1-3 eggs may be laid, but there are almost always 2. Incubation is 27 days and is performed by both partners, with the female spending more time on the nest than the male.
Incubation starts when the first egg is laid.
The resulting differences in age and size of the chicks means that when food is scarce, the older, larger chick gets more, and the youngest frequently starves to death within its first few days. The chicks have dark brown down, and are paler below. By 2-3 weeks, they spend most of the time swimming, though they still rely on their parents for food until they are fully grown. Fledgling takes place at around 7 weeks. Behavior Though loons are generally extremely awkward on land, red-throated loons have been known to travel long distances on land.