Reading: Johnsons Sea Cucumber
Johnsons Sea Cucumber
Parastichopus johnsoni
conservation STATUS : Safe for Now
climate CHANGE : Not Applicable
At the Aquarium
This species is not presently on exhibit at the Aquarium .
Geographic Distribution
Northeast Pacific Ocean .
Habitat
benthic dwellers, this sea cucumber species lives on the flaxen seafloor at depths of 30-400 meters ( 100-1300 feet )
Physical Characteristics
Johnsons sea cucumber, an echinoderm, has a long, tube-like, about cylindrical soft body which like its echinoderm relatives, sea stars, sea urchins, and backbone dollars, exhibits five-part isotropy. however, alternatively of the rigid test ( endoskeleton ) of other echinoderms, the ossicles ( calcareous plates ) of this ocean cucumber ’ second skeleton are minor and wide spaced. Its mouth is surrounded by little tentacles tipped with ticket cilium. The body of a Johnsons ocean cucumber is bright orange to red in color, accented by white tentacles and tube feet .
Sea cucumbers do not have a brain, heart, or lungs. alternatively of a central nervous system, they have a boldness ring with radial nerves, along with a steel net within the skin that can detect chemicals and touch.
Read more: Jian Bing, Chinese Crepes (煎饼)
Size
To 40 centimeter ( 16 in ) long
Diet
Sea cucumbers feed by processing detritus gathered by filtering the seafloor sand and mud sediments. In addition to plant and animal remains, Johnsons sea cucumber may besides process small know prey. sand is taken into the mouth, sifted, and expelled. Food particles are retained .
Reproduction
Sexes are separate in most sea cucumbers. Eggs or sperm are broadcast into the water column where external fertilization occurs. The embryonic and larval increase of a sea cucumber may be quite boring, making it unmanageable for ocean cucumbers to repopulate or recover after a decrease in population .
Behavior
little is known about the behavior of Johnsons sea cucumbers in the violent. They move by using their tube feet to inch along the ocean shock while flexing their tube-like bodies binding and forth through the water. Living in the benthic zone, Johnsons ocean cucumber inches along the seafloor as needed to find food or escape depredation .
Adaptation
These ocean cucumbers absorb oxygen by forcing water through hollow, branched organs called respiratory trees. This requires the sea cucumbers to quickly process large amounts of water that is taken in and expels through the anus .
As is coarse among sea cucumbers, a Johnsons sea cucumber can shed its internal organs, ( self-eviscerate ), to escape predators. The caducous organs may confuse, entangle, or distract a marauder by providing a commodious bite and give the sea cucumber a probability to escape. After such an consequence, a sea cucumber will find a safe position to hide while its inner organs grow back .
A ocean cucumber has a identical compromising body structure that gives it the ability to fit through minor crevices. It can loosen a message under the skin called catch collagen that forms its body wall. As a result, its body becomes about liquid in nature. It can then tighten the social organization of its cells to again firm its body.
Conservation
Although this species is not presently harvested commercially for heathen seafood, early species of sea cucumbers in the genus Parastichopus, including the California sea cucumber ( P. californicus ) are in danger of being overharvesting. many sea cucumber species have already been significantly reduced in numbers. Sea cucumber species ’ boring embryonic and larval growth rates alone increase the dangers posed by over reap .
Sea cucumbers are vulnerable to ocean contamination because, as percolate feeders, they ingest plastic particles that drift to the seafloor as nautical snow .
Special Notes
The California sea cucumber, P. californicus, is known as a bipolar feeder. It is able to take in food from its talk and is besides able of taking in food from its anus .
