Answer:
Sea urchins are spiny animals found in the aquatic habitat. They have similarities as the hedgehog and are referred to as Sea hedgehog.They feed on algae.
They are exposed to these conditions which include:
Environmental conditions- Changing water temperature and algal bloom
Predators- Crabs, Eels, Fish, Sea otters, Bird, Man
Environmental Toxins- Irgarol, Diuron, Polychlorinated biphenyl congeners.