If you've been noticing your lobsters are dying more often, it may be time to check their health. Many parasitic infections are not fatal to lobsters, but they can cause chronic low-level mortality. Lobsters may suffer from chronic low-level mortality due to parasitic infections in the digestive system, gills, and heart muscle. A parasitic infection that has caused significant mortality in Maine impoundments in recent years is Mugardia. This parasite enters through a wound and actively consumes the lobster's blood cells. It may die within minutes or even hours..