The Life Cycles of Ribbon Leeches

Spawning

• The ribbon leech lives for approximately two years, dying right after spawning. The ribbon leech, as well as all other leeches, are hermaphroditic, which means they possess both male and female sexual organs. Reproduction is accomplished by reciprocal fertilization, in which one ribbon leech injects sperm into another leech using a spermatophore. The sperm then reaches the female reproductive organs of the reciprocal leech where the eggs are fertilized. As all leeches are capable of producing both sperm and eggs, all leeches can produce their own offspring. The spawning of ribbon leeches typically occurs in the middle of July.

Eggs

• Once the eggs have been fertilized, the ribbon leech will then deposit them in a cocoon or pod. These pods or cocoons are made of a secretion produced by the ribbon leech's glands. Once the cocoon has been fully produced, the eggs are deposited within the pod and then attached to a solid surface. The eggs develop inside the pod for several months before hatching. Incubation time for ribbon leeches varies, though most will hatch in the late summer or early fall.

Juvenile

• The juvenile portion of the life cycle of the ribbon leech begins when the eggs have hatched from the pod. When they hatch, ribbon leeches will be incredibly tiny and hard to see with the naked eye. During the few months between hatching and the winter, juvenile ribbon leeches will scavenge for food in their water source or tank. Once winter sets in, the leeches go dormant until the beginning of the spring, as the cold temperatures and lack of food sources make living difficult for juvenile leeches.

Adult

• Adulthood is reached after the ribbon leech revives from dormancy and feeds, continuing to grow over several seasons. After its first period of dormancy, the leech will feed throughout the spring, summer and fall months, growing large enough to be considered regular or light, large-grade bait. A ribbon leech will not spawn during its first year of life. Instead, after spending the warmer seasons feeding and growing, it will again become dormant until the following spring. Once the July of the leech's second year of life begins, it will spawn and then die.