ed.

Nests were variable in size. Some were remarkably small in relation to
size of the kites, and would scarcely have been credited to this
species, had not the kites been seen sitting on them. Nests were from
10 to 18 (average 14) inches long and from 10 to 14 (average 11.7)
inches wide, in forks or crotches of branches. The branches supporting
the nests were from 11/2 to 10 inches in diameter. The nests were
constructed of twigs of approximately pencil size. Of 37 nests at the
Park, 29 were in cottonwoods, six were in willows, and two were in
elms. The figures probably reflect the relative numbers of each of
these species of tree rather than any clear-cut preference of the
kites. By the time nesting has begun the trees have leafed out, and
the nests are well concealed.

At the time of my visit to the Park, July 18 to 22, nestlings were
well grown, and were beginning to feather out. On August 4 and 5 the
young were well feathered, but flight feathers were not fully grown
and the young remained in the nest or perched on nearby branches. On
August 21 to 24 the young were fully fledged, and were able to fly
strongly but they still spent most of their time perching and those of
a brood tended to stay near together, usually in the nest tree.

In a total of 261/2 hours of observation, 148 feedings were
observed--on the average one per 10.7 minutes. The interval changed
from an average of 12.8 minutes for 62 feedings on July 19 to 21, to
8.5 minutes for 59 feedings on August 4, and to 10.8 minutes for 27
feedings on August 21. The longer interval on July 19 to 21 may have
resulted from the greater furtiveness of the adult kites at this stage
in their nesting cycle. Nests usually were watched through field
glasses at distances of 50 to 100 feet. Ordinarily kites are not
disturbed by the presence of a person at these distances, but when
delivering food to the nest they seemed somewhat distracted and
sometimes stopped only momentarily then left, still carrying the food.
Usually they swooped at the observer when leaving; rarely they swooped
at him as they approached the nest. All observations were between
10 a.m. and 5 p.m., and there was no obvious trend according to time.
Earlier and later in the day the rate of delivery is probably less.
The kites are notably late risers, and their activity increases
gradually after sunrise; in late afternoon activity tapers off again.
In 89 feedings, the average visit to the nest lasted 5