Organic Matter, Bacteria Doom Sea Stars to Oxygen Depletion
For more than seven years, a mysterious wasting disease has nearly killed off sea star populations around the world. Some of these species stand at the brink of extinction.
New Cornell-led research suggests that starfish, victims of sea star wasting disease (SSWD), may actually be in respiratory distress – literally “drowning” in their own environment – as elevated microbial activity derived from nearby organic matter and warm ocean temperatures rob the creatures of their ability to breathe.
“As humans, we breathe, we ventilate, we bring air into our lungs and we exhale,” said Ian Hewson, professor of microbiology in the College of Agriculture and Life Sciences. “Sea stars diffuse oxygen over their outer surface through little structures called papulae, or skin gills. If there is not enough oxygen surrounding the papulae, the starfish can’t breathe.
A healthy starfish is presented in Ian Hewson's laboratory. Sea stars along the Pacific Coast are not so fortunate, as large amounts of organic matter may be robbing them of an ability to breathe.