The Stentor is one of the largest single celled protozoa, growing as large as 2mm. The one pictured here, however, is nowhere near that size. Their behavior is similar to that of the Vorticella, in that they can be free swimming or they can attach themselves to other objects - usually the pond's bottom. When startled they quickly retract into a ball, then slowly emerge into their characteristic trumpet shape. They feed on the bacteria from decaying vegetable matter. They are most abundant and easily found in the fall when dead leaves and other vegetation falls into the pond and bacteria are plentiful. The red specimen here came from the bottom of my pond in the cold early spring among some decaying leaves. I have found the red specimens to be rare - at least in my pond. Back To Image Index Page