The Trumpeter Swan (Cygnus buccinator) mate for life. Should one partner die long before the other, the surviving bird often will not mate again for some years, or even for its entire life. The nesting season starts at the end of May. The pair build the large mound-shaped nest from plant material at an elevated site near open water, and defend a large territory around it. The pen (female) lays and incubates a clutch of 2-7 (usually 3-5) eggs, watching for danger while sitting on the nest....
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The Trumpeter Swan (Cygnus buccinator) mate for life. Should one partner die long before the other, the surviving bird often will not mate again for some years, or even for its entire life. The nesting season starts at the end of May. The pair build the large mound-shaped nest from plant material at an elevated site near open water, and defend a large territory around it. The pen (female) lays and incubates a clutch of 2-7 (usually 3-5) eggs, watching for danger while sitting on the nest. The cob (male) keeps a steady lookout for potential predators heading towards his mate and offspring which are called cygnets once they have hatched. Madison River, Yellowstone.
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