Bulletin Wisconsin Natural History Society [Vol. 13, No. 3 
17 2 
X. SUMMARY AND CONCLUSIONS 
(1) The paper concerns an ecological survey of the formation known 
locally as the Wingra Springs Region, situated at the southwest end of 
Lake Wingra, at Madison, Wisconsin, the investigation being with par- 
ticular reference to the avifauna. 
(2) This formation includes a portion of the lake, swamp, the large 
springs, woods, fields, and two temporary ponds. 
(3) The fomation is typically that of the Alleghanian area of the Transi- 
tion Zone, though there are Carolinian affinities. 
(4) The formation divides itself naturally into five associations, namely : 
(1) Limnetic, (2) Limniotic, (3) Fonticular, (4) Argian, (5) Sylvan. 
(5) Of these five associations, the Limniotic is the most important both 
because of its extent, and because of the abundance of life therein. 
(6) There is a definite succession of mammalian life within this associa- 
tion, as shown by the seasonal migrations of the weasel and meadow vole, 
and to a less extent by the muskrat and mink. The presence or abundance 
of these animals is dependent largely upon the moisture conditions of the 
association. 
(7) Data on the birds of the formation taken during two years show the 
presence of one hundred and sixty one species. These are listed in the 
associations in which they occur. 
(8) Except during December and January, the swamp far exceeds 
the fields and w r oods in number of species of birds. Except for a short time 
during the end of May and early June, the woods exceed the open fields, 
no doubt because of the protection afforded against severe weather. It 
should be noted in this connection also that, except during December, 
January, and early February, food is more abundant in the swamp than 
in the other associations. 
(9) There is a definite migration of resident birds within the formation, 
as exemplified by the migration of the ruffed grouse and quail. These 
birds winter together in the swamp and migrate elsewhere in the spring: 
the grouse to the woods; the quail to the open fields. In November both 
species return to the swamp. 
(10) It was found that a more or less definite horizontal zonation occurs, 
beginning with the central and deepest part of the lake, and extending 
shoreward to and beyond the woods. There are eight zones, each with 
its characteristic avifauna. 
(11) Of the eight zones, three are “water” zones. In these it is found 
that the birds are distributed with reference to their diving ability, the 
best divers being frequenters of the deepest-water zone. 
(12) Insufficient data are at hand regarding the vertical zonation, but 
there is evidence of the existence of zones in this plane. 
(13) It is pointed out from the examination of stomachs of birds taken 
in the different associations that the food of a species is of great importance 
in the limiting of its local distribution. 
