May, 1909 
THE USE OF MAGPIES’ NESTS BY OTHER BIRDS 
91 
follow an owl into an abandoned nest, and seem utterly at a loss to understand the 
prompt disappearance of the object of their pursuit. 
It is, however, in furnishing an ideal nesting site for several species of birds 
that the magpie bestows his greatest gift upon his bird neighbors. 
As has been mentioned before the two species whose occupancy of magpie’s 
nests is most prevalent are the Long-eared Owl and the Western Horned Owl. 
Both of these birds are notoriously averse to anything that bears a semblance to 
work, and the substantial last year’s nests of the magpie furnish an ideal recepta- 
cle for the great white eggs and the fluffy youngsters. 
Very little repairing is done 
to the abandoned structure 
preparatory to laying the eggs. 
A few feathers from the 
parent’s breast, and possibly 
those of some bird which has 
fallen a prey to the owl, to- 
gether with the accumulation 
of dead leaves, dirt and refuse 
found in old nests, form the 
“lining” upon which the eggs 
are laid. Capt. Bendirein his 
“Life Histories” states that 
the Western Horned Owl de- 
posits its eggs “occasionally 
inside but more often on the 
broken-down roof of these 
bulky structures. ’ ’ This state- 
ment will probably apply 
equally well to the Long-eared 
Owl as I have yet to find the 
first set of these eggs laid in 
a magpie’s nest which was 
domed over, altho the owls 
frequently make use of the 
interior of rooft nests as hid- 
ing places. 
Owing to the nature of the 
timber thruout a large portion 
of western America the great 
majority of magpie’s nests 
range in hight from 15 to 25 
feet above ground, altho occa- 
sional nests are encountered ranging upward to at least 60 feet above ground. 
However, the high nests do not seem to be preferred bv the above mentioned species, 
or in fact by any of the following mentioned species and it is safe to say that prac- 
tically all birds occupying magpie nests utilize nests varying from 15 to 30 feet 
above the ground. 
The Rocky Mountain Screech Owl, like all of the genus Otus, nests 
almost entirely in natural cavities or deserted woodpecker’s nests and I have never 
been fortunate enough to discover a nest in any other situation; but Beudire in his 
A MAGPIE’S nest appropriated by a pair of 
SPARROW HAWKS NEAR DENVER, COLORADO 
