Who would have thought that the symbiotic relationship between Goby Fish and Pistol Shrimp could be a surprisingly useful point of reference when discussing. Much like anemones and clownfish, pistol (snapping) shrimp of the genus Alpheus and certain bottom-dwelling gobies share a symbiotic relationship in which. Dave Wolfenden on a partnership sealed purely by mutual benefit between pistol shrimps and gobies â€” and how you can set up your marine.
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 Symbiotic Relationship Between Gobies And Pistol Shrimp
The shrimp cut the exuviae into pieces and transported them out of the burrow as soon as their new test hardened. 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 Symbiotic Relationship Between Gobies And Pistol Shrimp
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.
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.
Pistol Shrimps and Gobies: Perfect Partners (Full Article)
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. Giving and taking is incredibly developed in this symbiosis and likely evolved under the influences of the harsh environment with limited access to shelter and food.
Reproductive success depends on the activity of the partners. To protect their offspring, the gobies keep the shrimp away. Keep in mind that different species of goby associated with another shrimp species will exhibit some different behaviors than those that I observed. The capacities of both partners depend, for example, on body size. A tiny shrimp such as the reddish-white banded Alpheus randalli which can be found together with smaller gobies such as Stonogobiops species simply cannot handle the excavation work necessary for a larger fish, such as Cryptocentrus species.
The burrows of those tiny species are smaller and take longer to build. Maybe these species are mostly successful in a less harsh environment.
In other areas you can find tiny Stonogobiops species with the more massive Alpheus bellulus shrimp. That just shows that the gobies can change partners during their life history. Even apart from body size, the gobies will exhibit different behaviors, so choose species from the perspective of the shrimp and not just what you think will look good in your tank. Johannes Duerbaum is a marine biologist specializing in echinoderms and copepods.
He worked for Schuran Seawater Equipment and joined Sera seven years ago. 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. 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. Creating a Home for Gobies and Shrimps Shrimp Considerations When keeping pistol shrimps and gobies, the main area of concern is what the shrimp will do to the aquarium.
Pistol shrimps have one preoccupation: This in itself makes them very interesting and entertaining aquarium inhabitants, even without gobies, but it does need to be taken into consideration when setting up the tank.
The first requirement is to make sure that any rocks are securely positioned on the base of the tank—neither sitting on top of the sand or gravel substrate nor leaning on it. Pistol shrimps can easily undermine rocks when digging, leading to potentially tank-breaking landslides. A deeper bed is best, but about 3 inches 8 cm will do.
Corals sitting on the sand may be buried, or if small enough frags, for example carried off and used as building material. In my large reef tank a small pistol shrimp occupies an area of about 15 x 15 inches 38 x 38 cmwithin which only large rocks are safe. The shrimp will work around them. Apart from their desire for plentiful supplies of building materials, pistol shrimps are generally less demanding in the aquarium than many other crustaceans.
Like other types of shrimp, they should have a slow, careful acclimation when first added to the tank, but once established they seem to be rather hardier than, for example, cleaner or peppermint shrimps. They seem to be more tolerant of salinity and temperature swings. Feeding pistol shrimps is easy. They will eat frozen crustaceans Artemia, krill, mysid shrimp, and copepods as well as hunt their own food.
A certain amount of care is required when it comes to choosing crustacean tankmates for pistol shrimps. Large pistol shrimps although not the species generally kept with gobies are fairly formidable mini-predators and can easily capture and kill smaller aquarium shrimps such as Lysmata, Thor, and Rhynchocinetes species. Smaller ones, however, despite their snapping claws, are vulnerable to predation when molting, which, like other shrimps, they do regularly in order to grow. Immediately after molting, their new shell is very soft and provides little protection.
At this stage they are easy prey for larger shrimps such as Stenopus species. Even large peppermint shrimps Lysmata wurdemanniwhich lack large claws, can be surprisingly predatory and will eat small pistol shrimps. In large tanks such predation is less of an issue, but in nano aquariums it is best to keep your pistol shrimp as the only shrimp in the tank.
Choosing Gobies While pistol shrimps of all kinds can be housed in similar tanks, the size range of goby partners is so varied from under 2 inches [5 cm] for some Stonogobiops to around 10 inches [25 cm] for the largest Amblyeleotris species that it's important to choose an appropriate aquarium to suit the fish half of the partnership.
Shrimp gobies of all kinds, especially when teamed up with shrimps, are relatively sedentary, seldom moving far from their burrows, so they can be kept in smaller tanks than their size would suggest. Stonogobiops species in particular are ideal for nano reef aquariums, where the lack of larger fishes enables them to feel more confident and be more extroverted than they typically are in larger systems.