The Number of Eggs Laid by the 
Red-tailed Hawk. 
-BY J. W. PRESTON, BAXTER, IOWA. 
In late numbers of the Ornithologist and 
OOlogist there have appeared several references 
in regard to the color of eggs of the Red-tailed 
Hawk, ( Buteo borealis), and the number ol eggs 
in a set; therefore perhaps a few extracts from 
my field notes may not prove uninteresting. 
In a number of years collecting I have taken 
no fewer than seventy-five sets of eggs of this 
species, and examined many more, mainly from 
central Iowa. In this large series I have found 
but five sets of two eggs each, two having four 
each, and all the others contained three eggs 
each except one, which had but one egg — well 
incubated. 
In four instances the sets showed one egg en- 
tirely unmarked, while the other two were richly 
marked. About one third of the sets have been 
light colored, the very large proportion being of 
a bold, heavy pattern. I have usually found the 
ground color to be a light green, or greenish 
white, in fresh specimens, but fading after a few 
day’s incubation. The rich brown spots also 
fade to some extent. This, I believe to be also 
true of the eggs of many species of hawks, es- 
pecially noticeable in the case of those of the 
Marsh Hawk, ( Circus hudsonius), where the fresh 
egg is a beautiful light green, but it fades to dull 
white within a day or two. 
[It is probable that most of the readers of the Ornithol- 
ogist and Oologist will fail to agree with Mr. Preston that 
the typical clutch of eggs of the Red-tailed Hawk is three. 
Two is much more commonly the number. In a series of 
twenty-seven sets before the present writer, (collected in 
Pennsylvania, Connecticut, Iowa, Texas, and Mississippi,) 
there are nineteen sets of two eggs, six of three, and two 
of four. Mr. F. H. Carpenter has a series of thirty-six sets 
of two each, collected in Connecticut, Massachusetts and 
New York; and “J. M. W.” writes that “ the clutch of 
Buteo borealis is two.” — E d. 
O.&O. XI, July. 1886. p. tOX. 
The Number of Eggs Laid by the 
Red-tailed Hawk 
In the January number, 1886, of Tiie Ornith- 
ologist and Oologist, the present writer stated 
that the Red-tailed Hawk ( Buteo borealis), more 
commonly lays two than three eggs, and doubted 
Audubon’s “four or five.” Mr. J. W. Preston, of 
Baxter, Iowa, however reports having found a 
set of four eggs near that locality, on April 9th, 
1885. One of them was so badly broken that it 
could not be preserved, and Mr. Preston suggests 
that possibly it may have been laid by another 
female, which was driven from the nest by a sub- 
, sequent pair of birds who owned the other three 
I eggs. 
A PhiladelphiaOollection of Eggs of 
the Raptores. 
Buteo borealis. Red-tailed Hawk. Three 
sets of four, eight sets of three, twenty-five 
sets of two. Total: thirty-six sets, eighty-six 
eggs. 
O.&O. XIV. Mar. 1889 p.40 
Some of my Best Finds to June 8, 1892. 
A.E.Kibbe. 
May 6 . Set of two Red-tailed Hawk 
from a hemlock tree 78 feet from ground. 
O.&O VoL17, Sept. 1892 P.133 
(P.+ C 0 . X/. Ajm. Y(e. • S 3 . 
