Plus: size matters for female bighorn sheep, the hidden migration of North American dragonflies, helping trees move north and the great white who drew itself

Are icebreakers ruining narwhals’ summer getaway? Plus, Montreal’s whale-ward minkes, Canada’s first North Atlantic right whale visit of the year, a new K pod baby, and humpback and orca continue to clash

Welcome to the sinaaq, or floe edge, where landfast ice meets open Arctic Ocean and species thrive