At the Chicasaw Bluffs, on the Mississippi, I have seen some of these holes more than fifty feet below the surface, but generally beyond reach of the highest freshets. The hole is just large enough to admit the passage of a single bird at a time. The end is rounded and finished in the form of a common oven, to allow the pair or the whole brood to turn round in it at ease. Here, on a few sticks and feathers, the eggs are deposited to the number generally of six. They are pure white.
Incubation continues for sixteen days.
In the Middle States, these birds seldom raise more than one brood in the year, but in the southern usually two. Incubation is performed by both parents, which evince great solicitude for the safety of their young. The mother sometimes drops on the water, as if severely wounded, and flutters and flounders as if unable to rise from the stream, in order to induce the intruder to wade or swim after her, whilst her mate, perched on the nearest bough, or even on the edge of the bank, jerks his tail, erects his crest, rattles his notes with angry vehemence, and then springing off, passes and repasses before the enemy, with a continued cry of despair. I have not been able to ascertain whether or not the young are fed with macerated food disgorged by the parents into their bills, but I have reason to think so, and I have always observed the old ones to swallow the fishes which they had caught, before they entered the hole. The Kingfisher resorts to the same hole, to breed and roost, for many years in succession.