They're not, that I know of. They may be losing some of their habitat in some areas, but jellyfish, anenomes, coral and other of the invertebrates are thriving in other areas.
The ones that i know are endangered are corals. They are being lost through bleaching, and dredging.
small cnidarians and big cnidarians
cnidarians have no nervous system
The cnidarians are in the Kindom family
Yes, cnidarians are invertebrates.
Nope - Cnidarians are marine creatures !
cnidaria(similar to cnidarians)
Cnidarians reproduce asexually and sexually
There is none. Corals are cnidarians.
They provide a habitat for Cnidarians
Cnidarians live in water.
Cnidarians and Sponges are invertebrates
Jellyfish, corals, and box jellies are cnidarians.