After the eggs hatch, the territory has to provide food not only for ravenous nestlings, but for the parents as well. Hunting and feeding takes every waking hour. In the northern latitudes of Alaska, feeding time may extend to 21 hours a day. A robin makes an average of 100 feeding visits to its nest each day. Baby robins sometimes consume as much as 150 percent of their body weight in a 12-hour period, which means a good territory is essential for feeding a hungry family.
Robins spend much of their lives searching for one of their favorite foods, earthworms.
Most scientists now conclude that they find these worms by vision, thanks to experiments by an ornithologist named Frank Heppner. In his experiments, Heppner investigated all the robins' senses. To prove robins use vision, he needed to rule out the other senses robins might use to get information about worms. A list of the equipment he used is provided below. At this time they eat earthworms and insects.