For instance, scientists once observed a house wren provide 491 feedings to its nestlings in one day. Phoebes can feed the kids more than 800 times in a day. Titmice have been known to make up to 70 feeding trips an hour. While swifts may arrive only once an hour, that one feeding may contain 600 insects – a collecting average of one every six seconds.
What's more, hard-working bird parents raise broods without expectation of rewards. They can't hope for General Foods or Pampers to show up with help in exchange for product endorsements. They can't expect those baby beaks to give them even a small smile. Perhaps worse, they can't count on the kids’ taking care of them in their old age.