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observer has a chance, he should try to flush a grebe and acquaint him- 
self with it. Few birders have seen flying grebes, for the birds prefer to 
escape by diving. Often confusing on the water, a flying grebe looks like 
anything but a grebe, reminding one of a scoter, merganser, or even a small 
heron. 
Also in early April, returning Red-breasted Mergansers gather on 
Lake Michigan. The lake off Wilmette is a good place to see up to a 
thousand of these showy fish-eating birds. It is interesting to note that while 
fall flights of Red-breasted Mergansers are mostly females or immatures, 
the spring migration reverses this trend; flights are almost 100 per cent 
males. The answer to this may lie in the fact that wintering flocks in 
Florida and the Carolinas are immatures or females, while wintering flocks 
in New England are mostly males. Perhaps some cross-country migration 
takes place. 
Bonaparte’s Gulls appear in April to put on a spectacular, noisy show. 
Thousands may be seen around the Chicago harbors, Great Lakes harbor, 
and Waukegan harbor. Occasionally a Franklin’s or Little Gull may be 
found with the large flocks of Bonaparte’s, but almost daily birding is 
needed to see these rare visitors. Lake Michigan is not a place where rare 
birds can be seen every day. However, constant checking of favored spots 
and a small knowledge of weather should assure one of an occasional 
rare bird or a large migrational gathering. 
Four species of terns regularly occur on Lake Michigan in the spring. 
These are the Common, Black, Forter’s, and Caspian Terns, which arrive 
in late April and May. Common and Black Terns are regular visitors and 
both species nest in the Waukegan area. The Forster’s Tern is a regular 
but uncommon migrant, best distinguished from the Common by its silvery 
wing tips and lack of contrast between the rump and the upper part of 
the wing. 
The Caspian Tern is a prize “find” for midwesterners. It is seldom seen 
away from the Mississippi River or Lake Michigan. A birder will have to 
look fast to see a Caspian on the lake. Probably the best place to see 
Caspians is the lake shore from Waukegan north, usually with Ring-billed 
Gulls. The large red bill and gull size of the Caspian give the observer 
an unforgettable sight. 
In late May shorebirds make a quick, impressive showing on northern 
Illinois beaches. From Waukegan north to Kenosha, Wisconsin, large groups 
of Dunlin, Black-bellied Plover, Turnstones, and Sanderlings flock along 
the gravel beaches. A few miles inland in muddy fields one also sees many 
plovers and turnstones. The beaches on the south side of Chicago are 
fairly good for shorebirds, too, but seldom do they stay long when people 
are present. 
To be sure, other birds frequent Lake Michigan in the spring, but 
they are rare. A few Double-crested Cormorants go through in March and 
April, and Common Loons appear in mid-April. Lake Michigan is well 
worth several visits in spring for Illinois birders. 
1020 Ashland Avenue, Wilmette, Illinois 
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