BULLETIN 
OF THE 
WISCONSIN NATURAL HISTORY SOCIETY 
Vol. 13 SEPTEMBER, 1915 No. 3 
AN ECOLOGICAL SURVEY OF THE WINGRA SPRINGS 
REGION, NEAR MADISON, WISCONSIN, 
WITH SPECIAL REFERENCE TO 
ITS ORNITHOLOGY* 
By Alvin Robert Cahn 
I. Introduction 124 
The problem 124 
Methods and Equipment 125 
Acknowledgements 126 
II. Physical Features of the Investigated Area 
The Lake 126 
The Swamp 128 
The Springs 129 
The Woods 130 
The Fields 131 
The Pools 131 
III. Climatic Features 133 
IV. Life Zones 134 
V. Influence of Topographic Features on Bird Life 
The Limnetic Association 135 
The Limniotic Association 135 
Mammalian Succession 135 
The Spartina Society 136 
The Cornus Society 137 
The Fonticular Association . . 138 
The Argian Association 138 
The Sylvan Association 141 
VI. The Birds of the Area 141 
Abundance and Distribution 142 
VII. Avian Migration 146 
VIII. Avian Zonation 
Horizontal Zonation 149 
Vertical Zonation 151 
* A thesis offered to the University of Wisconsin for the degree of Master of Science, June, 
IS 15. 
123 
