Marine bryozoans form colonies of many shapes

[mouakter13]

All freshwater and most marine zooids are hermaphroditic, producing both sperm and eggs, not necessarily at the same time. Thus, there can be fertilization of eggs among colony members, but this is equivalent to self-fertilization because colonies typically form by asexual budding (cloning) of the initial zooid. In most species, sperm swim to a zooid in female phase, fertilize her few eggs internally; the fertilized egg and young larva are brooded either inside her body or in a special external chamber. A larva of freshwater species can contain a few new zooids, which start a new colony when the larva settles someplace. In addition to sexual reproduction and budding, freshwater bryozoans also produce vast numbers dispersal units. This mass of cells, produced asexually, may just fall country wise email marketing list to the bottom or may float away or stick to passing animals and floating vegetation. When conditions are right, the unit germinates, producing a new zooid and the start of a new colony.

. Some are branching, like corals, and some form leaf-like shapes. Many are flat and form crusts on rocks, shells, kelp, and submerged wood. Others sit like tiny bowls on the bottom or bore into a hard, calcareous substrate. Most live in coastal waters but some are recorded from depths of over six thousand meters.

Of course, bryozoans have predators. In marine systems, sea spiders and nudibranchs are important; grazers such as urchins also take some. I have not found much detailed information on predators of freshwater bryozoans, but snails are reported to eat certain ones and raccoons are reported to eat the gelatinous types. Fish and insects are listed as possible predators.