Tar-spot Sea Cucumber (Cucumaria pseudocurata)
Tar-spot sea cucumber hanging between California mussels (photo credit: Molly Sultany)
Description: Among other species of sea cucumbers, the tar-spot sea cucumber is a tide pool resident at Haystack Rock. These creatures usually only grow to be 1.5-3 cm long, but larger individuals can sometimes reach lengths of 3.5 cm. Each one can vary in color and pattern; you may see ones that are gray-yellow, light brown, or a darker brown-black color. Each one has five rows of tube feet that run along its body lengthwise. These tube feet are used for moving and for feeding. They also have 10 tentacles surrounding their mouth (8 of which are identical in length and 2 of which are shorter) that they also use to feed.
Habitat: Because of their small size, they are able to hide in crevices between rocks and creatures like California mussels in the mid to low intertidal zone. Geographically, they range from central British Columbia, Canada down to Monterey Bay, California.
Diet: Like other sea cucumbers, tar-spot sea cucumbers are suspension feeders, which means they capture bits of food (like plankton or detritus) that are floating in the water.
Tide Pool Tidbits:
These sea cucumbers are often found in large groups, sometimes up to 4000 individuals in one square meter!
Unlike other sea cucumbers that broadcast spawn (release eggs and sperm into the water to fertilize), tar-spot sea cucumbers brood their eggs underneath them for about a month before releasing them.
Reference: The New Beachcomber’s Guide to the Pacific Northwest by J Duane Sept, Race Rocks Ecological Reserve