Pearl fish and sea cucumber relationship test

H2 When presented with different species of cucumbers, pearlfish will prefer its To test the idea that there was intraspecific and interspecific competition (H1), we Host specificity of Carapidae in relation to Holothurian hosts After monitoring. And then, inevitably, the pearlfish would find you. And there are few better shelters than sea cucumbers, little mobile homes that the pearlfish initiates one of two relationships once inside: a commensal one, . Scientists Journey Into the Dark Side of Cannabis. Author: Matt SimonMatt Simon · test flight. PDF | The relationship between sea cucumbers (Holothuriidae) and H2 When presented with different species of cucumbers, pearlfish will . To test the idea that there was intraspecific and interspecific competition (H1), we.

Pearlfish and Sea Cucumber Symbiosis

We found through surveys and experiments that host specificity was not significant for the Carapidae. Our experiments suggest that interspecific and intraspecific competition does occur between Carapidae species.

Using statistical analysis, it was found that there was a strong correlation between Carapidae species association and Holothurian host location. Specific Hypotheses H1 Competition occurs between E. H2 When presented with different species of cucumbers, pearlfish will prefer its present host to other potential Holothuriidae host.

H4 Pearlfish exit their host at night for feeding. White House Wall, Public Beach, 2 and West Opunohu were the sites selected to collect and survey the abundance and distribution of the two species of host sea cucumbers.

The topography consists of a fringing reef that leads into a patchy crest reef. This site is also fairly shallow in depth ranging from 3 feet to 10 feet. West Opunohu contains a sandy floor with a patchy crest reef. Two species of Holothurians were used for this experiment. Thelenota ananas is a large species reaching up to a meter in length. The body is black with orange conical papillae arranged in a stellate fashion. Bohadschia argus is a common species and is characterized by two color morphologies.

The colors range from a light gray to a dark reddish brown both containing a mottled spotting pattern. Carapidae are eel-like fishes that lack scales and pelvic fins but have pectoral fins. Although most species of Carapidae live in the body cavities of invertebrates, some are found to be free living up to meters in depth Myers Two species of carapids were used in this study.

Encheliophis boraborensis is brownish in color and has very small eyes. They possess small, stellate melanophores that are visible near the jaws and increase in number with age Markle and Olney They have an extremely elongated body and an enlarged swim bladder, which takes up ninety percent of it visceral cavity.

The eyes are extremely enlarged and melanophores are present along the body, however, they are 3 somewhat hidden Markle and Olney They also have an elongated body as well as an enlarged swim bladder. Using scuba and free diving techniques, we performed collections at the three sites outside Opunohu Bay. At each of the sites, we did four 50 meter transects, two of which were shallow and two of which were deep.

Cucumbers were counted on 5 meters of each side along the 50 meters. We then used the transects to measure the distribution and abundance of the Holothurian hosts. Collections of the two species of Holothurians occurred from Nov 8th to Dec 2nd of Specimens were collected at various depths and time periods throughout the day to examine Carapidae distribution patterns and to be used in our experiments.

The collected specimens were brought back to the lab, placed in salt-water tanks, and observed daily and nightly. Pearl fish were extracted by depleting the hosts of oxygen using a shallow container of water and confining the cucumber in the container until the carapid exited its host. To test the idea that there was intraspecific and interspecific competition H1we tagged carapidae and its hosts in the lab to observe if competition occurred between the tagged carapidae and different carapidae for hosts.

Competition was measured by observing aggressive behavior biting, cannibalism between the same species as well as different species of carapidae.

Pearlfish enters sea cucumber anus - rare weird Vieques Island sea life

In order to assess the concept of host specificity H2we tagged pearlfish and placed them in a tank with two or more species of sea cucumber including its present host.

Observations were made of the twelve trials on the behavior and decisions of the tagged pearl fish as to what host it decided to enter. The presence of association cues between the Holothurians and Carapids H3 was investigated by the following method. The tagged pearl fish was introduced to a holothuriidae host and observations of association cues i.

To test the idea that carapids were nocturnally active H4night observations were done to see if the fish really did exit its host for feeding purposes. Results Intraspecific and interspecific competition between two carapid species for a Holothurian host Intraspecific and interspecific competition was found in both species of carapids.

It was found that competition occurred inside the body cavity of the cucumber between several carapids. In one trial, two male E.

Dissection of the host cucumber took place finding one male, one female, and an adult C. Within the stomach of the surviving male E. This was verified in another replication as a juvenile C. Other evidence of competition included bite marks on the specimens used in these trials and on other carapids extracted from collected cucumbers.

In one such case, evidence of interspecific fighting between the two species of carapids was observed. Host specificity of Carapidae in relation to Holothurian hosts After monitoring 12 trials of host preference, the results indicated no selectivity of carapids for their original hosts. Both species of carapids either entered the first host that they came across or hosts other than their own. In 12 trials there were only 2 cases in which the fish did find its original host. We performed these trials with 2 adult C.

Each fish appeared to smell the length of the body of its potential host, doing lengthy surveys a number of times before actually entering the anus.

Both species of carapids demonstrated this behavior. It was also observed that both species of carapids seemed to listen along the body of the host almost as if trying to detect the presence of another occupant inside.

A type of knocking around the anus area was initiated by the fish as a means of encouraging its entrance into the cavity. Nocturnal activity of two species of carapids After one all night survey of a B. Discussion Many exciting observations were made throughout this venture and several of the statements made in our references were disproved with our findings.

Many reported pearlfish as entering tail first, but we found headfirst entry prominent among our many specimens Myers Homei was reported as living independently from other species, while out of four cases of hosts containing multiple carapids, we found this species living with E. Boraborensis three of those instances Trott and Trott It was stated in Micronesian Reef Fishes among other places that the pearlfish come out to forage at night, but our observations presented different information Myers No foraging occurred during our tests, but these observations were done in aquaria and could be construed do to stress of the specimens.

Evidence of competition was prominent among our observations. One example of this is the relationship between the sea cucumber and the pearl fish. Sea cucumbers are echinoderms that have a shape very similar to soft cucumbers 1. These invertebrates crawl along the floor of the ocean and can reside in both shallow and deep areas of the ocean.

They are omnivorous and usually eat small particles and detritus they find on the ocean floor. The sea cucumber can grow between 2 to cm and can live to be between 5 and ten years old 2. Spawning for the sea cucumber usually occurs between June and August. The sea cucumbers release their sperm and eggs in the water and allow fertilization to take place.

These fertilized eggs continue to develop into larvae, which become suspended in the water column for up to 70 days. Eventually, these planktonic forms settle on the ocean floor, where they change into tiny little juvenile sea cucumbers. Growth is slow for these invertebrates, and it can take up to 4 years for the cucumber to reach adult size 3. They have long, slender bodies that lack scales and they usually have transparent skin.

The tail of the pearl fish is long and pointed, and the anus of this fish is located close to its neck. Pearl fish typically grow to be about 15 cm long 4. The female pearl fish releases clumps of eggs late in the summer to begin the life cycle. These eggs rise to the surface and hatch, turning into a specific type of larvae called vexillifers. These larvae live among the plankton until reaching a length of about 7 to 8 cm.

At this point, the larvae develop into tenuis.

Pearlfish and Sea Cucumber Symbiosis

These forms descend to the ocean floor and begin their search for food and a host 5. The pearl fish will constantly be on the lookout for sea cucumbers to create a symbiotic relationship. Once a pearl fish Onuxodon or Carapus finds a sea cucumber Holothuroideait immediately begins to smell around to distinguish between the head and the anus of the cucumber 6. Once it finds the anus, the pearl fish works its way into the rectum of the sea cucumber, eventually being completely engulfed in the digestive canal of its host.

There it will spend the day inside, using its host as a form of protection.