In 1960, Turnbull refuge workers began reintroducing trumpeter swans; 37 cygnets arrived over four years, and 21 years after losing his mate, Solo fathered a new brood

A single male swan spent two decades returning alone to the same lake every spring, long after his mate had been killed and his eggs destroyed. That bird, later nicknamed Solo, became a key hope for restoring trumpeter swans to eastern Washington after an ambitious reintroduction programme very nearly ended in failure.

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