What Eats Giant Duckweed?

Giant duckweed is an aquatic floating plant commonly found in calm waters such as ponds and lakes. Though it occurs naturally in some environments, it can become an invasive species in other ecosystems when prime conditions cause the plant to overpopulate and take over an aquatic environment. One way to control the growth of giant duckweed is to introduce its natural predators, such as waterfowl and some fish species, to the water system it is taking over.

Identification

The scientific name for giant duckweed is Spirodela polyrhiza. Though the largest of the duckweeds, giant duckweed is small in size relative to other plants. Giant duckweed "leaves" (what looks like a leaf is actually an extension of the plant stem called a frond) are round in shape and typically 1/16 to 1/14 inches in length. There are normally one to four leaves per frond. Each frond has three or more roots that protrude from the frond's bottom side. The upper side of each leaf is green in color, while the underside of each leaf is red in color.

Habitat

Giant duckweed is typically found in aquatic environments such as ponds, lakes, marshes and slow streams. Because giant duckweed is a fast-growing plant, aquatic managers may introduce species (such as grass carp or tilapia) to a pond or lake system to control the growth of giant duckweed.

Birds

Given its name, it should come as no surprise that waterfowl, such as several different species of ducks and geese, eat giant duckweed. These animals typically feed on the whole giant duckweed plant.

Fish

Fish such as goldfish, grass carp and koi also eat giant duckweed. These fish are typically recruited to eat giant duckweed in fish tanks and ornamental ponds. Like birds, these fish typically eat the entire duckweed plant.

Livestock

In some African and Asian countries, giant duckweed is used as a food source for cattle and pigs.