Sea stars are one of the most recognizable marine species and typically have a five-part body consisting of a central disk and radial symmetry. Size, shape, color, and texture are quite diverse in the 1,800 species that inhabit our oceans worldwide. Like their close relatives in the echinoderm phylum, such as sea urchins and sea cucumbers, sea stars share many of the same characteristics. Their mouth is located on the animal’s underside, and they use tube feet as a mode of locomotion.
Sea stars are predators and scavengers. Their diverse diet includes other echinoderms, including spiny sea urchins. Sea stars evert their stomach over their prey and either digests their food outside of their body or swallow it whole. Others prey on sessile animals like sponges, anemones, or coral polyps using the same method of everting their stomachs. A few other species eat detritus material, algae and clams, and oyster shells.
Sea stars, like most echinoderms, reproduce by simultaneously releasing eggs and sperm into the water column. Once fertilized, eggs hatch into free-swimming larvae that eventually settle at the bottom. Another means of reproducing is by detaching an arm (autotomy) or splitting apart (fission), allowing a completely new animal to form.
*Due to the constant rotation of animals back to the ocean, we cannot guarantee the presence of any specific animal.