A BALTIMORE ORIOLE CENSUS 
KATHERINE GILMORE AND H. E. JAQUES 
The question with which this article is concerned is one that 
was under discussion in the Ornithology Class at Iowa Wesleyan 
College. The original problem was to discover how many pairs 
of Baltimore orioles nest yearly in the town of Mount Pleasant 
where the college is located. , As the investigation was carried 
on and interest deepened, the scope of the problem was enlarged 
somewhat to include a study of the determining factors in an 
oriole's selection of a nesting place. When the problem was first 
undertaken, the town, which has a population of about four thou- 
sand and covers an area of one and one-fourth square miles, was 
divided into six districts of about equal extent and two students 
were appointed to search each district for orioles’ nests and to 
note the species of tree in which they were found. This work 
was done in February, and, as there were no leaves on the trees, 
each swinging pouch was quite conspicuous and the matter was 
not one of great difficulty. The complete report was as follows : 
Kind or Tree 
Soft Maple , 
White Elm 
Box Elder . 
Hickory ... 
Cottonwood , 
Hard Maple 
Hackberry . 
Apple ..... 
Walnut .... 
Number oe Nests 
60 
.40 
....10 
............. 5 
3 
2 
1 
1 
1 
123 
The fact that but two-thirds as many nests were found in elms 
as in maples seemed worthy of investigation since all available 
bird literature advanced the opinion that the oriole preferred an 
elm tree. In this matter the Botany Class assisted with a census 
of the elms and the soft and hard maples six inches in diameter 
or larger in Mount Pleasant. This second census was as follows : 
Kind oe Tree Number oe Trees 
Soft Maples .' 1392 
Elms ......' 814 
Hard Maples ............... ......... 817 
