I unintentionally neglected to mention the diameter of the holes in yesterday’s Mystery Photo. They were approximately 5” wide. Bank Swallow nest holes, similar looking and also dug into banks, are anywhere from 1 ½” to 3” in diameter. Being colonial nesters, Bank Swallows also typically have many more nests in a given bank (see photo inset) than Belted Kingfishers, which usually have one but may have several in a single bank, only one of which they occurpy during a given season.
After courtship takes place, a pair of Belted Kingfishers flies to a sand bank in a road cut, landfill or sand/gravel pit that is usually near water, and proceed to excavate their nesting tunnel. The male begins to slash and probe the soil with his bill while the female remains perched nearby, calling the distinctive rattling call of Belted Kingfishers. She eventually lends a hand (bill) and they call to each other throughout the construction of their nest.
The tunnel extends three to six feet into the bank, ending with an unlined chamber. (A bed of undigested fish bones, scales and arthropod exoskeletons from regurgitated pellets eventually forms.) Typically the tunnel slopes upward from the entrance, which may help drain any water that accumulates in the nest. Furrows directly below the bottom of the nest hole are made by the feet of the birds as they enter and leave the nest.
Belted Kingfishers are starting to lay their six to seven eggs which will begin hatching in three to four weeks. (Photo: female Belted Kingfisher)
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