Wednesday, June 16, 2010

Atlantic Mudskipper, Periophthalmus barbarus


Common Names: Atlantic mudskipper, mudskipper, common mudskipper, mudhopper, 'skipper.

Scientific Name: Periophthalmus barbarus (Linnaeus, 1766) [really old sources sometimes call them Gobius barbarus]

From Where? West African coast area and the nearby islands. Fishbase say's they're also found on and near Guam, interestingly. Generally found on mud flats and around mangrove swamps throughout its distribution.

Size: According to legend, this beast reaches a whopping 25cm (10 inches!), which I have honestly never seen, but to this day has kept me away from West African mangrove swamps. They commonly attain 15cm (6 inches) though.

Foodstuffs: In the wild they'll take whatever they can get their mouth around, which can be quite a lot - small crabs, insects, and supposedly baby mudskippers too. In captivity they'll quite happily munch down on most frozen and live foods: anything from bloodworm to krill to fish, they'll be happy. Some 'skippers convert to dry food diets, but even then try to include some frozen/live foods from time to time.

PS: for a real show, throw a live insect in their enclosure. Sit back and enjoy.

Water: Mudskippers are hardy little guys, and can tolerate anything from freshwater to brackish to marine and even beyond that. Despite this, you'll find they do the best when you keep them in 'normal' brackish water over the long term. Keep the SG between 1.003 and 1.010 for the best results.
They're also not fussy on temperature, but you've got to keep it tropical, 24 degrees C (76 degrees F) and upwards.
Quality is (as with pretty much anything else with these guys) all chilled, so long as you don't leave the water stagnant and rotting. Mudskippers have a much higher tolerance for nitrogenous wastes as compared to most other fish. But in the ethics of good fishkeeping, do a water change at least once a month, and make sure the water is well filtered.

Aquarium Specifics:



Ah, the most important aspect of 'skipper keeping.

The first thing you'll need is some area of land for them to, well, crawl, climb and skip on. Failing to provide this will result in your mudskippers sticking itself to the glass and crawling up. As cool as it looks, it's pretty tiring for your mudskipper. And yes, they can drown. They absorb most of their oxygen through their skin, so land in now definitely in your interest.
In the more basic setups, some people just stack rocks and/or wood onto which the skipper can climb onto. This works well, especially for smaller setups, but it doesn't look very much like a mudskipper habitat. This is where you make your own beach? How, you ask? Well, slope some sand in the tank by putting more sand/gravel on the one side than on the other. Use rocks or sheets of glass to act as retaining walls to prevent the beach from slumping and e voila: you have beach. How much beach you need is dependent on how many muddies you'll be keeping. Males are aggro to each other, females not so much so. You need 900cm squared (1 square foot) of beach for a male and female to share, or otherwise the same measurements for each male.

It won't really matter to the mudskippers, but incorporating a beach normally leaves you with pretty shallow water, which also ends up being ideal for mudskippers. Shallow water is not only easy for them to get out of, but it so happens to be similar to conditions they'd live in in nature. Notice how, in most of the pictures I've posted, they only submerge themselves until only their eyes are sticking out the water. They like it that way.

Now you'll need some filtration. If you have the mostly recommended shallow water, you'll have a problem with internal filters, barring using them horizontally. The better idea is to use either a canister filter or a sump, with the added benefit of keeping out of your tank and making the whole setup seem a whole lot more natural. Another bonus in using a sump is that you can shove your heater in there too, which is a safety feature in a sense. Seeing that mudskippers like to climb everywhere, a heater in their actual tank is a burn threat. Sump + heater = good idea.

To add to the habitat, use roots (that look like mangroves, because mangroves can be tricky to grow in a skipper setup) and maybe allow some other plants that enjoy humidity (like some ferns) to grow in the upper parts of the tank. Make it really natural, although not biotope specifically correct.

Compatibility: They don't mind mixing with other fish, although normally the shallower water doesn't hold other fish well. I prefer to keep mudskippers in a tank to themselves and meet their requirements specifically.

To make the best scenarios, just keep a male with one or two females in a setup. Keeping multiple males together ends up becoming messy (gory etc). Also, try to avoid mixing different species of mudskippers. I haven't tried this myself but I can see it ending badly.

Specific Problems: Read above.

Rarity: The most common mudskipper, even places that aren't pet stores sometimes get them.

Similar Species: There are a few species of mudskippers, and a handful of gobies that look a little bit like mudskippers. These are most easily identified by the bright blue specks on their cheeks and generally larger size, as well as their availability.


SEE ALSO: Aye, 'skipper



Saturday, June 5, 2010

Red-tailed catfish tiger shovelnose hybrid



Common Names:
Red-tailed catfish tiger shovelnose hybrid, RTCxTSN, TSNxRTC, red-tailed shovelnose catfish, leopard catfish

Scientific Name: Technically, as a hybrid, it doesn't have one, but I suppose you'd be able to call it Phractocephalus hemiolopterus x Pseudoplatystoma faciatum. Planetcatfish calls them Phractocephalus sp. hybrid.



From which our beloved hybrid came from

From Where? Again, this isn't a real species with a real natural distribution. It's parent species both come from South America though, in the Amazon and some of its tributaries.

Size: It's hard to tell - as displayed in several other hybrids of fish, there isn't an exact size to which this hybrid will grow. Normally, one would expect the size that either parent species would attain; in this case both the red-tailed catfish and the tiger shovelnose catfish are both capable of reaching over a meter (3 feet plus), even in captivity, so expect the same for this bugger...

... although on that same note, hybrids also have a tendency to actually get to bigger sizes than their parent species in something termed 'hybrid vigour'. Just be prepared to house a very, very large fish.

Foodstuffs: Absolutely anything. Keepers of the regular red-tailed catfish will tell you that what will go down their throat, does, and this absolutely applies to this hybrid. Smaller fish will happily live on sinking pellets, small frozen foods (like market shrimp) as well as live food if that's your fancy. The bigger fish will eat anything from whole sardines, slivers of chicken, beefheart, and probably your offspring too.

Feed until they're looking a little plump, then leave them until their stomach goes back to normal. This normally means that you don't have to fed them every day.

Avoid decor and equipment that can fit into the mouth of this fish, and change/protect your tank appropriately as the fish grows. Many stories arise about such fish swallowing gravel, rocks, pieces of filters and suction cups. It isn't known if swallowing such items is dangerous for the fish, but afterwards they throw it up. Along with whatever went missing is their stomach acids and whatever they were busy digesting at the time, which HEAVILY pollutes the tank. Get ready to do a big water change should this happen.


Water: Not fussy at all. Keep the pH between 6.0 and 8.0, and the temperature within the tropical range, and you'll have a happy monster catfish. They're not especially whiny about water conditions either, but try to keep the water clean. They're heavy eaters and heavy messers, so weekly or fortnightly water changes are recommended, as well as a really good filter system.

Aquarium Specifics: A biiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiig tank. And you'll need one from the start, because they're not slow growing, either. My little guy grew from a mere 10cm (4 inches) to 20cm (8 inches) in just over a month, and that was when I was feeding sparingly. In cases like this, a tank isn't recommended, but rather a tropical pond, which can satisfy their space needs much easier.



As far as decor goes, its best to keep it sparse. They'll appreciate the extra space. Large, smooth, solid rocks work best, so long as they can't get knocked over by this (potential) giant. Sharp rocks and wood are both dangerous to this catfish.

Compatibility: You'll actually find this to be a docile fish. Well, aside from eating tankmates anywhere from up to half its own length and less, that is. They have huge mouths, huge appetites and long whiskers. Sometimes they'll test to see whether another fish can fit in their mouths by actually trying it out.

Lessons learned: keep with fish of equal size and larger (if applicable).

Specific Problems: Giganormous size, tank-mate tasting and bulky nature are the only problems, all of which are easily resolvable. However, this catfish is best left to specialists who already know how handle these bad boys.

Rarity: Not too rare. It shouldn't be allowed to be common either, since few people are capable of housing them.

Similar Species: Their hybrid traits vary from fish to fish, some possessing more red-tail catfish traits, some having more shovelnose traits, others looking like a complete muddle up. They can be told apart from Phractocephalus hemiolopterus by their longer mouth and spotty patterning, and apart from Pseudoplatystoma by their reddish tails and by the predominance of black on their body.

Aye, 'skipper

Sorry, but the pun was absolutely necessary.

Enjoy some pics of my mudksippers (Periophthalmus barbarus).