Birds of Isle Royale in Lake Superior 
Majestic Isle Royale, largest 
iiland in Lake Superior, and Lake 
Superior itself, largest fresh-water 
lake in the world, were important in 
the development of the Great Lakes 
region, particularly during the early 
period of exploration. George Shiras 
3d regarded Isle Royale as the most 
beautiful and the most interesting 
island in the Great Lakes (18)1/. 
Others described it as the enchanted 
island, the wonder island of the north; 
some likened it to a battleship accom¬ 
panied by a fleet of destroyers. In- 
' dians of the 17th century feared the 
island, and referred to it as the 
floating island. 
Radio-carbon dating of wood 
recovered from prehistoric mines in¬ 
dicated that the Indians were mining 
copper on Isle Royale at least 3,300 
years ago (5.) * With the ending of 
prehistoric mining, the island seems 
to have been abandoned except for 
occasional visits by fishermen and 
trappers (10). Copper mining was 
tried intermittently in the last 
half of the 19th century, but none 
of these operations proved econom¬ 
ically feasible, and explorations 
were abandoned by 1900. 
The American Fur Company oper¬ 
ated five fishing posts on the is¬ 
land from 1837 to 1842 although the 
fur industry could have been a side¬ 
line ( 13) . In 1840 the island was 
reported to be destitute of game 
with the exception of a herd of "rein¬ 
deer." Commercia l fishing continues 
1/ Numbers in brackets refer to 
the references at the end of 
this report. 
today, making it the most enduring 
enterprise on the island, although 
depredations on food fish by the sea 
lamprey have diminished it to a mar¬ 
ginal industry. 
Interest in the island as a 
natural area, valuable for its 
scenery and wilderness character, 
as well as its interesting fauna, 
history, and archeology, brought 
about its establishment as a National 
Park in 1946. 
Located in northwestern Lake 
Superior, at latitude 48°N. and 
longitude 89°W., Isle Royale (fron¬ 
tispiece) lies 13 miles from 
Thunder Cape on the Canadian north 
shore. The southwestern part is 
18 miles northeast of Grand Portage 
in Minnesota, from which it is 
visible on clear days. The finger¬ 
like northeastern section, with its 
many peninsulas, bays, and harbors, 
is 30 miles east of Fort William 
and Port Arthur, Ontario. South¬ 
eastward, it is approximately 55 
miles to Michigan's Keweenaw Peninsula. 
The 210-square mile National 
Park is an archipelago--approximately 
200 islands and numerous rock out¬ 
crops surround the main island which 
is 45 miles long by 8 miles wide at 
its widest point. The topography is 
a series of northeast-southwest 
parallel ridges and valleys, formed 
by differential erosion of alternating 
layers of Keweenaw basalts, conglomer¬ 
ates, and sandstones. Greenstone Ridge 
is the highest and most prominent and 
forms the backbone of the island. 
Other prominent ridges are Minong, 
