Some Observations of the Nesting Habits of the Eastern Phoebe

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The eastern phoebe (Say ornis phoebe) is an unpretentious, drably colored bird, which does not ordinarily attract attention to itself. Its nesting habits, however, are very interesting, and this paper is an account of observations made on a pair of the species throughout one nesting cycle. The study was conducted at the Forestry and Biological Station of the University of Minnesota, which is located in Itasca State Park in northwestern Minnesota. Like seventeen other phoebe nests observed in the park, this one was constructed of mud reinforced with fine grasses and lichens, and lined with down. Like the others, it was statant and adherent to a man-made structure. This particular nest was located on a ledge above the door of a cabin occupied by the writer and his family during a five-week period. The nest was under construction when first observed, and its progress was noted until completed two days later. A blind was prepared at a safe distance, so that the nesting and succeeding activities could be studied without unduly disturbing the birds. Phoebes tolerate some degree of molestation by humans in spite of the fact that they appear timid and flighty. Ordinary passage through the door beneath the nest occasionally flushed the occupants, but only temporarily interrupted their activities. The interior of the nest and its contents were periodically examined with a piece of broken mirror that was attached to a yard stick in such a way that observation was possible from beneath. Such examinations were made when the nest was unoccupied by the adults. In this manner one pure white egg was found the morning after the nest was completed. Neither parent was observed in attendance during the daylight hours which followed, but the mother spent the ensuing night on the nest. Two days elapsed before a second egg was noted, and on each of the three succeeding mornings another was deposited, until a total of five were present. Incubation commenced immediately, with the female taking complete charge. The male spent considerable time sitting on a nearby clothesline and chirping a two-syllabled song. He would also bring food to the female during the day. It was not known where he spent the nights, but he would make his appearance at dawn. Sixteen days elapsed before the first egg hatched, and within three more days all but one had opened. The fifth did not hatch and was expelled from the nest several days later. It was decided to observe feeding activities and obtain information regarding trips to the nest, possible sources of food and other movements from the time of hatching until the fledglings left home. A time schedule was planned so that observations would be made for one hour each day. These periods were so planned that activities were noted during different hours of each day. For example, on the first day the birds were watched during the first hour of activity in the morning, the second day on the second hour and so on until the end of the cycle. Records of trips to the nest were kept to get some idea of maximum and minimum activitiy. One entire day was devoted to making a complete check from pre-dawn to the cessation of activities at dusk. In addition to these periods, frequent observations were made during irregular times by the writer and members of his family. The first observation after the young were hatched indicated that the male took no part in feeding the young directly but would pass the insects to the female and she in turn would feed the nestlings. She would also leave the nest periodically to collect food. Most of the insects were captured on the lawn near the cabin and in a tall grassy area toward the east. The prey brought in at this time was small enough to be carried within the mouth. The female was repeatedly seen to fly to a spot about twenty rods southward, where she would drop to the ground, remain a short?