Along the Pacific coast, a silent catastrophe has unfolded since 2013. More than 5 billion sea stars, from Alaska to Mexico, have died in what scientists call one of the largest marine wildlife epidemics ever recorded. Known as sea star wasting disease, it hits fast. Arms twist, lesions open, limbs detach, and within days, the animal disintegrates into nothing but a puddle of tissue. The most devastating losses came for the sunflower sea star — a massive predator with up to two dozen arms and a