Motobdella montezuma facts for kids

Motobdella montezuma is a special kind of leech that lives only in one place: Montezuma Well in central Arizona, United States. This amazing creature is active at night. It hunts tiny water bugs called amphipods, specifically Hyalella montezuma, which also live only in Montezuma Well. The leech finds its prey using a special "listening" ability, like a quiet sonar, and then swallows them whole!

About the Montezuma Well Leech

Adult M. montezuma leeches can grow up to 71 mm (2.8 in) long. This measurement includes the special suckers they have at both their front and back ends.

Where the Leech Lives

Montezuma Well

The M. montezuma leech is related to other leeches in the Erpobdella group. These relatives are found all over North America, from Alaska down to Mexico. However, M. montezuma is unique because it is only found in one single pool of water. This special pool is called Montezuma Well. It is located within the Montezuma Castle National Monument in Yavapai County, Arizona.

How the Leech Lives and Eats

Montezuma Well has a very high level of carbon dioxide in its water. This makes it hard for fish to live there. Because there are no fish, there's an open space for other creatures to become the main hunters in the water. Even though many different invertebrates (animals without backbones) live in the well, the M. montezuma leech almost always eats only one type of food. Its diet is made up almost entirely of the Hyalella montezuma amphipod. This amphipod is also found only in Montezuma Well.

Behavior and Hunting

The M. montezuma leech is nocturnal, meaning it is active at night. During the day, it rests at the bottom of the well. This helps it avoid predators like waterfowl (birds that swim). As night comes, the leeches swim up towards the surface of the water. They hunt amphipods near the surface. This is a very rare behavior, as most leeches do not hunt in open water like this. They find their prey using a special sense called passive sonar. This means they listen for vibrations or sounds made by their prey. Once they find an amphipod, they swallow it whole! This unique way of moving up and down in the water each day and night, called diel vertical migration, is only known to happen with leeches in Montezuma Well.

Life Cycle and Reproduction

Like many other leeches, M. montezuma is hermaphroditic. This means each leech has both male and female reproductive parts. When they reproduce, two leeches will fertilize each other. After this, the leeches lay their eggs inside a special cocoon. This cocoon is filled with nutrients to help the eggs grow. The leeches place the cocoon deep enough in the well to keep it safe from predators like ducks. When the eggs hatch, tiny juvenile leeches emerge. These young leeches are able to take care of themselves right away.