The Pistol Shrimp or Snapping Shrimps of the Alpheus shrimp, family are great diggers, and constantly create and maintain burrows in the sea. Dave Wolfenden on a partnership sealed purely by mutual benefit between pistol shrimps and gobies â€” and how you can set up your marine. The Goby Fish and Pistol Shrimp Know a Thing or Two about Alliances thought that the symbiotic relationship between Goby Fish and Pistol Shrimp could algae), then identify which companies might be partnered with to help fill the gap.
Amalgamating the couples of fish and shrimp was not an easy task. If same sexes are in a small tank, it often ends in severe trouble—the shrimp are able to kill each other in an aquarium. Therefore I kept them as far apart as possible in separate tanks until I could identify the sexes of the shrimp female shrimp have a more broad abdomen and more broad pleopods.
I also kept the young gobies separated. By changing the partners in one tank, I could easily find out if two specimens would go together, which is the indication for different sexes. In the next step, I brought both couples together in the observation tank. I kept the interior of the tank simple: The shrimp started building the burrow immediately after I introduced them in a little cup and directed them into a gap I made under a piece of live rock. Then the fish were added.
It did not take longer than an hour, and the double couple was together. During the next days, the burrow grew.
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The shrimp transported all excavated material and pushed it outside the burrow. They used their claws to push the sand like a little bulldozer. This astonishing skill can only be performed if the goby is out to guard their safety.
When the tunnel system grew, the partner behaved differently under subterranean conditions. The narrow space in the burrow causes them to squeeze their partners against the burrow wall.
The fish tend to wiggle through the burrows with force and no hesitation toward their crustacean partners.
Due to the action, parts of the burrow system would often collapse. A fish buried under sand stays there without panic the shrimp can smell it and waits until the shrimp digs it out and begins to repair the burrow. The main way into the burrow can be up to 2 feet long during the first days of excavation. Soon after, side ways are constructed, which can be as short as 2 inches. They can be driven forward and later form an exit to the surface, or they are extended to form a subterranean chamber.
Repeatedly, I could observe the shrimp molting in these chambers. This happens during the night every two to four weeks. The next morning, I would find exuviae close to them, and the female was carrying eggs on her abdominal legs if the shrimp are in good condition, molting and egglaying coincide.
The shrimp cut the exuviae into pieces and transported them out of the burrow as soon as their new test hardened.
Pistol Shrimps and Gobies: Perfect Partners (Full Article)
Hatching of the zoea larvae seems to happen overnight, which makes sense to avoid predators as long as possible.
The currents caused by the beating of the pleopods must pump the eggs out of the burrows, where they become a part of the plankton. The shrimp are omnivorous and collect large pieces of frozen fish positioned close to the entrance of the burrow. They collect the food and transport it immediately into the burrow, where they feed on it.
However, outside they can also be observed eating algae growing on rocks. The shrimp directly gnaw with their mouth pieces on rock where algae is growing. Even more fascinating was that I found parts of the algae Caulerpa racemosa inside the burrow system, though it grew more in another edge of the tank.
It took some time until I could observe that the shrimp cut these algae with their claws if they get access to it. However, that can only happen when fish and shrimp are on a coexcursion outside the burrow.
In one instance, after cutting, the shrimp lost the algae due to the currents in the tank. But the unexpected happened: The goby immediately took action and grabbed the Caulerpa with its mouth. That moment, the shrimp lost antenna contact with the fish and quickly rushed backward to the entrance. The goby transported the lost food to the entrance and spit it out into the entrance of the burrow where the shrimp was waiting.How to Keep Pistol Shrimp and Shrimp Gobies
The fish was actively feeding the shrimp! I tested this observation and pulled algae off the rocks. When the fish was in the entrance of the burrow, I threw a 1. The goby directly approached it while it was still floating in the water column, collected it and brought it to the burrow. That collecting behavior could be induced up to five times repeatedly. The shrimp handled the algae inside the burrow in the meantime. I could never observe that the shrimp were keeping algae in certain parts of the burrow.
There was not a special storage chamber for algae pieces. Instead the algae pieces were pushed around, and the shrimp fed on them here and there. After some days, the algae disappeared completely. Breeding in the Burrow While the reproduction of the shrimp is not spectacular, that of the gobies bears some peculiar aspects. Close to mating, the male and female gobies start a wild circular dance in an extended side corridor of the burrow. They stimulate each other head to tail, which causes sand and gravel to fall from the ceiling.
The gobies can successfully mate only when the shrimp are healthy and have hard tests. The female does not go back to the breeding chamber—the male fish is the only one to care for the eggs.
Usually, he moves the approximately 2, eggs which can easily be done, as the eggs are attached to each other and form a bundle by moving his pectoral fins backward and forward.
He swims around the eggs once in a while, which supplies oxygen to the eggs. Oxygen is low in chambers deep in the sand; only intensive care will keep them oxygenated. The male goby protects the eggs against a potential predator in the burrow: In fact, the shrimp couple never gets access to the fish eggs. The male goby is busy guarding the eggs during this period and rarely leaves the burrow. If he does leave, he closes the breeding chamber with sand. He pushes sand into the entrance of it with his head or tail.
When he comes back, he just wiggles through the pile of sand to come back to the eggs. After seven to 10 days depending on temperature or perhaps oxygen supply the larvae are ready to hatch. Hatching always happened at night with my fish, and by morning the larvae had all left the burrow, probably guided by the light. Many of the creatures that we keep in our aquariums have unexpected features, but there are probably few that can compete in this respect with pistol shrimps, or snapping shrimps, as they are also known.
While their commensal relationships with gobies are remarkable enough and are the main focus of this articlethey can lay claim to two much more remarkable things. First is the noise they make, a popping sound that is quite like a gunshot, which gives them their common name. The sound is slightly alarming to hear in the aquarium, as it sounds similar to cracking glass. Some species of pistol shrimps rival whales for the accolade of noisiest creature in the ocean—pretty impressive given the size difference!
To quantify the sound, the intensity has been measured as decibels at 3 feet 1 meter from the shrimp: Pistol shrimps use a specially adapted claw to fire a pulse of water at their prey; the water shoots out of the claw at around 62 miles km per hour. In its wake, the water leaves a tiny bubble, and the sound is generated as this bubble collapses. The whole process lasts less than a millisecond. Using high-speed cameras to film pistol shrimps in action, scientists observed that a flash of light is also emitted as the tiny bubble in the wake of the pulse of water collapses.
This is weird enough in itself, but what it indicates is that the tiny collapsing bubble reaches a temperature of almost oF almost oC —not far from the temperature of the surface of the sun.
This is probably the highest temperature that can be achieved by any living organism. Perfect Partners The partnership between pistol shrimps and gobies is a good example of commensalism, where both parties in the relationship benefit.
The goby benefits from the shrimp's digging and construction skills, having access to a well-built burrow. Pistol shrimps have poor eyesight, and they use gobies as an early warning system to detect predators. Gobies tend to hover just outside the shared burrow, catching passing zooplankton or small benthic invertebrates.
In many cases the shrimps maintain contact with the gobies by using their long antennae, and the gobies signal to the shrimps using specific fin flicks. Some species of goby also appear to feed their shrimps, spitting food into the burrow, and even without such deliberate actions it's possible that the shrimps may feed on fragments of food that the gobies drop.
Meet the Gun-Slinging Shrimps While many species of pistol shrimps are found in a wide variety of habitats, only a few are commonly kept in aquariums.
These are species of the genus Alpheus. It has a white body with complex brown or reddish-brown markings. Some individuals have purple markings on the legs. Both associate well with many different goby species. Another very attractive, but less often imported, species is the golden pistol shrimp often referred to as A. One other Alpheus pistol shrimp deserves a mention, A.
There are other Alpheus species, and other pistol shrimps, that find their way into aquarium stores, but they are often of unknown species. And Their Goby Guests Several genera of gobies associate with pistol shrimps.
They can be and usually are kept without shrimps, and most are good aquarium fishes in their own right. They are generally hardy and easy to feed, but many even the robust-looking Cryptocentrus gobies can be quite shy, and they are prone to jumping from open aquariums or even through gaps in aquarium covers.
They often seem to be both bolder and less prone to jumping when kept with shrimps—perhaps having an expertly constructed bolt-hole close at hand makes them more confident. To overcome this, make sure that some food drifts past their hiding place e.
The most common aquarium imports are species of Amblyeleotris, Cryptocentrus, and Stonogobiops, although other species are sometimes offered for sale. There are 38 species of Amblyeleotris, which in the wild associate with a variety of Alpheus shrimps.
The Symbiotic Relationship Between Gobies And Pistol Shrimp
Many of them look quite similar: There are some more distinctive species in this genus, notably Randall's shrimp goby A. Also distinctive, if seldom seen in aquariums, is the giant shrimp goby A. Four species are seen relatively frequently in the aquarium trade: Stonogobiops species usually associate with Alpheus shrimps, particularly A. Cryptocentrus species have a more robust look than most other shrimp gobies, with frog-like heads and big mouths. They tend to be more aggressive towards related species, and in the case of the larger species even towards other tankmates, than other shrimp gobies.
Not many of the 34 species find their way into the aquarium trade with any frequency. The most popular species is the yellow watchman goby C. It grows to around 6 inches 15 cm and is grayish but with bright pink spots and blotches as well as smaller neon-blue spots. Numerous other Cryptocentrus species are occasionally offered for sale, and while relatively little is known about their care, they can probably be expected to behave in a similar way to their more familiar congeners.
In the wild, Cryptocentrus associate with a variety of Alpheus shrimps.