Migratory Birds of the Great Lakes University of Wisconsin Sea Grant Institute
 about habitat birds + science 20 birds
aerialist raptors
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Trumpeter Swan Nest and Eggs

Trumpeters build their nests on top of muskrat or beaver lodges, or they pile sedges and cattail tubers into a mound. The cob (male) uproots the vegetation and transfers it to the pen (female), who piles it high, then uses her body to form a depression for the eggs. The same nest structure may be used from one year to the next. Usually, water surrounds the nest making it difficult for a mammalian predator to surprise the pair. The nests may reach a diameter of six feet or more.

Beginning in late April to early June, the pen lays one creamy white egg every 36-48 hours until a clutch of up to nine eggs is complete.    next page >>