Plumatella bryozoans

Plumatella spp. · Aquatic life

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NativeBryozoan

Also called Moss animals, Plumatella emarginata, Bryozoans, Plumatella repens

How to identify Plumatella bryozoans

Brown, branching, rootlike or mossy tubes crusting on hard surfaces
Tiny feathery crowns of tentacles poke out of the tube tips underwater
Can form thick fuzzy mats inside pipes, valves and screens
Tiny dark brown disc shaped statoblasts (resting buds) in the tubes

Similar species

Often mistaken for algae or aquatic moss, but it is not green and does not feel slimy; under a hand lens the tentacle crowns retract when touched. Freshwater sponges are spongy and gritty rather than tubular.

Profile

Season	Grows late spring through fall; dies back in winter, leaving statoblasts that sprout the next year.
Starts	Growth picks up as water warms past about 60 F
Light	Prefers shade
Depth	Shallow to moderate depths on hard surfaces
How it spreads or reproduces	Statoblasts carried by water, birds and equipment; colonies also break apart
Habitat	Undersides of rocks, docks, logs and leaves, and inside irrigation pipes, intakes, screens and sprinkler lines; common in canals and reservoirs.

Why it matters in a lake

Harmless filter feeders that indicate good food supply in the water, but they are a frequent cause of clogged irrigation pipes, filters, valves and sprinkler heads in canal fed systems.