The chestnut lamprey is a jawless native fish that can attach its mouth to the side of another fish, such as a lake trout. The lamprey releases a substance that
prevents the lake trout's blood from clotting and uses its tongue to create
suction that draws a steady flow of blood and body fluids from the lake trout.
This type of lamprey rarely kills the lake trout before detaching and moving on.
The relationship between a chestnut lamprey and a lake trout can best be
described as - *