Plant Family: Badderwort Family, Lentibulariaceae
Common Bladderwort (Utricularia vulgaris) is a submergent aquatic species often found int the quite heavily vegetated areas of lakes and marshes. The plant has pretty little yellow flowers that protrude from the water’s surface and from a distance resemble pea flowers.
The most interesting feature of Common Bladderwort, and others of the genus its the presence of bladders. These structure all the plants to consume animals and obtain nutrients. When an animal such as a waterflea gets close it triggers hairs on the bladder, which cause the bladder to suddenly swell. This creates a vacuum which sucks in the zooplankton. Even tiny, newly hatched fish can fall victim to the bladders. You can tell when the bladders are full because they are dark and filled with digesting zooplankton, and other invertebrates.
Also see Horned Bladderwort