Birds
Belted Kingfisher
Megaceryle alcyon · also called kingfisher
Follow almost any clear river in North America and sooner or later a stocky blue-grey bird with a ragged crest will burst off a branch ahead of you, flying low over the water and firing off a loud dry rattle. That is the belted kingfisher, and it is patrolling a territory it may hold all year.
Overview
Megaceryle alcyon breeds across Canada and the United States wherever there is clear water and a bank to dig in. It is blue-grey and white with a shaggy crest and a heavy dagger bill, and it hunts small fish, crayfish, and tadpoles by plunge-diving from a perch or a hover.
The brighter female
Both sexes have one blue chest band, but the female adds a second rusty band across the belly, so she is the more colourful bird — an unusual reversal among birds, probably tied to how strongly both sexes defend feeding territories.
Life in a tunnel
The pair digs a burrow 1 to 2 m into a vertical earth bank, sloping up so it drains, and the female lays five to eight white eggs on a floor that gradually fills with coughed-up pellets of fish bone and crayfish shell.
Status
Least Concern but slowly declining, mainly from the loss of the natural earth banks it needs to nest in and from disturbance at nest sites.
Belted Kingfisher: common questions
Is the belted kingfisher the same as the kingfisher in Europe?
No, they are different species in the same family. The bird known simply as the kingfisher in Britain and Europe is the common kingfisher, a tiny, dumpy, electric-blue and orange jewel of a bird about the size of a sparrow. The belted kingfisher is a North American species, much larger, at roughly the size of a jay, and coloured in blue-grey and white rather than blue and orange. Both share the family traits of a big head, a long heavy bill, tiny feet, a taste for fish, and a habit of nesting in tunnels, and both give a loud call, but they are not the same bird.
Why is the female belted kingfisher more colourful than the male?
In most birds where the sexes differ, the male is the showier one, because males compete for mates and females choose. The belted kingfisher reverses this, and the female has an extra chestnut band that the male lacks. The reasons are not fully settled, but belted kingfishers are strongly territorial year-round, both sexes defend feeding territories in winter, and females are slightly larger and often dominant at the nest. The brighter female plumage may be tied to that assertive, territorial role rather than to courtship. It makes the belted kingfisher one of a small number of birds where you can sex an individual at a glance by which one looks fancier.
How does a kingfisher dig a nest tunnel?
Both members of the pair work at it, using the closed bill as a pick to loosen the soil and their small but strongly fused feet to kick the loose material backwards out of the hole. They choose a clean vertical face, often a river cutbank, a road cutting, or a gravel pit wall, high enough to be safe from flooding and predators. A finished burrow is usually 1 to 2 metres long, occasionally up to 4, and angles gently upward so rain drains out. Digging a new tunnel takes several days to a couple of weeks, and a pair may reuse or extend an old one.
What does it mean when you hear a kingfisher rattle?
The dry, rattling call is the belted kingfisher announcing itself, and it is usually given in flight as the bird moves between fishing perches or when it is disturbed and flushes from a branch over the water. Because the call carries so far and the bird patrols a linear territory up and down a stretch of river or shoreline, the rattle is often the first sign that a kingfisher is present. Both sexes call, and the sound also functions as a territorial signal, warning other kingfishers off that length of water.