The bladderwort: No ruthless microbe killer

A carnivorous water plant with tiny traplike bladders dotting its leaves may not deserve its reputation as a relentless predator, says a Florida scientist.

Floating in water, bladderworts grow filaments that support tiny bladders (lower arrow), about 370 bladders per whorl. Flower stems reach above the water to bloom (upper arrow). Richards

A survey of bladderwort plants in the Everglades found far more bladders harboring living organisms than dead ones, reports Jennifer H. Richards of Florida International University in Miami. Although the plant does kill insect larvae, it offers a safe home for smaller organisms, which may pay rent in nutrients. The bladderwort, or Utricularia purpurea, “is not like a bear trap,” she says, but more like a terrarium.