Mysterious underwater growths resemble alien life form

This swimmer accidentally discovered a colony of gelatinous masses attached to a submerged tree in the lake at his cottage. He was following a large bass when he came upon what he thought was a collection of algae growths. These mysterious looking blobs had the appearance of a coral and the texture of a slimy and rubbery ball. Algae is a plant and it is immobile, as these blobs were. They looked like some sort of alien life form.
What the swimmer had actually found was an animal, or more correctly, a collection of them. These are freshwater bryozoan. Freshwater bryozoans are microscopic aquatic invertebrates that live in colonies. They can form into jelly-like clumps that often attach to docks or submerged sticks. Bryozoan colonies can reach 30 centimeters (one foot) in diameter. The base of each tiny bryozoan is attached to an underwater surface. Its body has an outer sleeve-like structure and a mass of organs called polypide that moves inside of it.
This swimmer found a slice in the side of one of the masses and he pulled the flap aside, revealing a mass of algae and other structures. These animals use tentacles to filter diatoms and other microscopic organisms from the water.
It is believed that bryazoan evolved from a marine worm. They can multiply themselves by budding, and they also grow eggs and sperm to reproduce. Larval forms will go through complete metamorphosis. Freshwater bryozoans form hard, round statoblasts inside their bodies that act like seeds.
These creatures are a sign of a clean lake. It is a positive sign of a healthy ecosystem. The only negative aspect is that they can clog drainage pipes or water filters.
This collection of bryozoans was found in a lake in Ontario, Canada.