The skin lesions are the first sign that something is wrong. Then limbs fall off and the body disintegrates, collapsing in on itself as it liquefies. In the end, what was once a sea star is only a puddle on the ocean floor.
Since 2013, sea star wasting disease has killed so many starfish along the Pacific Coast that scientists say it's the largest disease epidemic ever observed in wild marine animals. Where there used to be dozens of stars, scuba divers now report seeing none.