The Coming Crisis: 300 million red admiral butterflies estimated from Windsor to New Brunswick Butterflies have migrated across Eastern Canada this spring in unprecedented numbers, reflecting the warm winter throughout North America and raising alarm bells about what it might mean for other species. "It's probablythe most exciting year for butterflies that Canada has ever seen," said Jeremy Kerr, a professor of biology at the University of Ottawa. Estimates from the field suggest there are 300 million red admiral butterflies from Windsor to New Brunswick — more than 10 times what would be seen in a typical year. Numerous other butterfly species have also arrived or appeared in greater numbers, Kerr said. Source: The Coming Crisis