MICHIGAN ACADEMY OF SCIENCE. 
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(Fig. 15.) At the south end of the island some of the ridges are largely 
without trees (Fig. 8). Most of our time was spent on this island, head- 
quarters, as in 1910, being established at the light house, which is located 
on the north shore (Fig. 2). The localities on this island referred to are 
as follows: Light-House Point — the northernmost point, on which the 
light-liouse is situated (Figs. 2-3). East Point — the most eastern point 
(Fig. 5). Rattlesnake Point— the point lying between Light-House 
Point and South Point on the west side of the island (Figs. 11, 13). 
Horseshoe Bay — the bay on the east side of the island. The pond (Figs. 
9-10) on the west side. 
Little Charity Island (Fig. 20) lies about three miles southwest of 
Charity and is much like it except that the forest, which never was as 
luxuriant as on Charity Island, has been largely cut off. There is an 
abundance of wild berry and other bushes, which create better conditions 
for the ground species, such as the sparrows, which bred there much 
tnore commonly than on Charity Island. 
Gull Rock (Figs. 16-19) is only a sand and rock islet which has been 
left bare by the lowering of the lake level during the past thirty years. 
(In 1880 Captain McDonald sailed his boat over the present site of this 
island.) It is now almost completely covered with water at every hard 
storm especially in the spring, but during the summer about one-fourth 
of an acre is exposed. The vegetation consists principally of smart- 
weed ( Polygonum hydropiper L.) and a few scrubby willows. 
GENERAL OBSERVATIONS. 
Two general facts in regard to the breeding birds of the island are 
worthy of record. In the first place the number of species and indi- 
viduals is small. At present only 37 species are known to have bred on 
the islands, and even the most common species were with few exceptions 
limited to three or. four pairs. The paucity of species and individuals 
may be explained by the small number of habitats, the smallness of 
the area, which restricts the habitats, and the distance of the islands 
from the mainland. The principal land habitat (for breeding birds) is the 
forest on the ridges on Charity Island, but even here only three species 
(crow, red-eyed vireo and cedar bird) were at all common, and the crow 
was not confined to the habitat or the island. The next most extensive 
habitat is the interior of Little Charity Island, which has been mostly 
cleared and supports a relatively large number of song sparrows and field 
sparrows, and barn swallows about the buildings. The third most import- 
ant bird habitat is undoubtedly Gull Rock, which is inhabited only by 
the common tern which breeds there by the hundreds, and the beaches 
on the other islands. The other habitats such as low thickets, quiet bays, 
ponds, etc., are very restricted and hence afford a limited food supply and 
support a meager ornis, many of the most common forms on flic main- 
land not being found here. 
The position of the islands in respect to the mainland also with little 
doubt serves to restrict the bird life, for it is apparent that the islands 
or the proper habitat when present may be missed by the bulk of the 
species on the spring migration. This is shown by the fact that the 
breeders vary from year to year. Only a few examples can be given 
owing to the short period covered by investigations, but these are with 
little doubt typical examples of what occurs annually in the population 
