National parks with current or historic freshwater sponge populations in the National Capital Region. Sponges can be identified to the species level only by examining the sponge’s gemmule structure with a microscope. They can reproduce sexually, or asexually when small pieces are broken off and grow into new sponges or when the sponge forms gemmules-tiny reproductive spheres that can overwinter and later hatch and form new sponges.

For this reason, many people mistake freshwater sponges for algae, but sponges have a coarse texture, and are not slimy like algae.įreshwater sponges filter organic particles and bacterioplankton from water for food and also consume some products produced by their symbiotic algae. The species Ephydatia muelleri found in the National Capital Region (NCR) is often green because of algae that lives in the structure of the sponge.

They are invertebrates (have no backbone) and do not have organs, but instead have specialized cells that help them filter water for food. NPS/Tonya Watts Basics of Freshwater Spongesįreshwater sponges are non-moving organisms that live at the bottom of water bodies. Sponges can reproduce through these tiny round gemmules that can hatch to form new sponges.

How far do sponges move around