Wolverines are among the most climate-vulnerable mammals in North America, with reproductive success tied directly to persistent spring snowpack that is rapidly declining across their range.
Wolverine climate vulnerability creates a welfare emergency that unfolds annually across the species' range as spring arrives progressively earlier. Each year of premature snowmelt means more female wolverines attempting to raise cubs in dens that collapse before kits are mobile, resulting in the death of vulnerable newborns through hypothermia and exposure. This is not an abstract population projection but a recurring welfare catastrophe — cubs that cannot survive den collapse experience cold, hunger, and death over hours to days. For surviving adults, climate-driven habitat reduction forces wolverines into smaller, more isolated areas with less prey availability and higher intraspecific competition. The welfare case for strong climate action as an animal welfare intervention is nowhere more starkly illustrated than in the wolverine — a species whose reproductive welfare is directly tied to a climate variable we have the capacity to affect.