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Barbs The Cyprinids (named after Cyprinus, the European Carp) are an enormously successful
family of strictly freshwater fish, with
over 340 genera and some 2000 species, found
on every continent except South America,
Australia and Antarctica. The relationships
of groups of families within two huge Cyprinid
subfamilies (Cyprininae and Leuciscinae)
are being discussed by ichthyologists, now
using conservative mitochondrial DNA sequences. The Barbs are omnivores, with a need for greens. If you don't give Barbs some green feed, like spirulina flakes or, even better, blanched spinach leaves, they'll be reduced to munching on the decor. Just give them zucchini slices and they'll leave the Hygrophila alone. Barbs devour duckweed even faster than it grows. Breeding links. A good basic description of setting up to breed barbs is laid out by Albert Thiel at Master Index of Tropical Fishes. The Center for Tropical and Subtropical Aquaculture (CTSA) at the University of Hawaii, cooperating with the U.S. Department of Agriculture, posts an e-manual packed with information on commercial breeding of Tiger Barbs, in order to encourage the nascent aquarium fish farming industry in Hawaii. For example, I've seen here that using a stiff spawning brush reduces the number of eggs that get eaten! And there's some material on the regrettable intentional hybridization of Barbs in the trade too! Mike Edwardes keeps excellent illustrated Tiger Barb breeding notes at his webite, "Mike Edwardes Tropicals." And don't miss Randy Carey's article "Spawning and raising Tetras, Barbs and Rasboras" at his site www.characin.com. Breeding. Here's how I'd set up to spawn easy barbs, such as Tiger Barbs. Give them a 10-gal. tank. If you can set it in an east-facing window where early sunlight will strike it, all the better. Reassure the rest of your family that this is quite temporary. Set up your tank with some aged gravel. Cut a rectangle of plastic netting with about half-inch mesh to fit the bottom of the tank, and support it with lengths of plastic tubing or whatever, so that it sits about an inch off the gravel. Add some floating stem plants like Elodea or Ambulia or some chunks of floating corkbark with streamers of Java Moss. Use a very well-cycled sponge filter from an established planted tank that hasn't had any disease in it. Fill the tank with water from the barb's home aquarium mixed about half-and-half with de-chlorinated water. The aquarium should be "instantly" cycled. To make sure, add a few drops of ammonia til it just registers on your test kit. Test again in 24 hours for ammonia and nitrite. If both ammonia and nitrite are undetectable, you're ready to go. If not, you have to wait until the cycle is complete. Put the fullest, most robust female into the tank. Let her settle a couple of days and feed her lightly on live foods (you don't want flakes drifting down among the gravel). Now add the liveliest male with the reddest snout. Raise the temperature two degrees every day, til the temperature stands at 80ºF. Keep a watch on your pair: they lead up to the act with increased chasing, which the female initiates almost as much as the male. They nip at each other's anal fins and they can find themselves nose-to-tail, chasing each other til they're spinning down towards the gravel. They may just spawn without any more encouragement. If they haven't, do this: in the evening, just before "lights out," do a 50% water change with cooler water, dropping the tank temperature quite quickly as low as 74º. Cover the tank with a towel. In the morning, remove the towel, and they'll spawn in the sunlight, probably within a couple of hours. (If they don't spawn that day, start raising the temperature again and repeat the process.) Pale sticky eggs, no bigger than a dot, will fly everywhere. The spawners will eat many of them, especially as they finish spawning. Net the pair out. The eggs are invisible down among the gravel. The eggs will hatch in about two days. Before they hatch, do another 50% water change, to remove the milt that would otherwise start to be broken down by fungi and bacteria. This would be the time to color the water with methylene blue, to forestall fungus, but you have to change it out, for the newly-hatched fry are sensitive to it. Once the fry are free-swimming, start to feed them on vinegar eels and microworm for a few days, til they're all taking newly-hatched brine shrimp. The benthic fauna that has colonised the sponge filter, and more protozoans along the strands of Java Moss will also provide food for the newly free-swimming fry. Puntius (lateristriga x) everetti (Clown Barb). P. lateristriga was described in 1842 by Valenciennes. Boulenger named P. everetti in 1894 to honor its discoverer. Have these two similar species been carelessly hybridized in captivity? The "Clown Barb," Puntius everetti, has caused confusion since it was first
imported, initially to Hamburg on the eve
of World War I, then to New York, where it
was miscalled "Barbus lateristriga" until the "real" B. lateristriga turned up in 1932. The English called this
the "Spanner Barb." The confusion
is excusable, for both these barbs have crisp
silver and black juvenile patterns but develop
more blurred and colorful mature patterning.
Even the ichthyologists have been misled:
in 1957 Klausewitz declared that a "Barbus zelleri" that had been described by Ahl was identical
with a juvenile P. lateristriga. V.P. Vasiliev wrote an article, "Chromosome numbers in fish-like vertebrates and fish" in the Journal of Ichthyology, 1980, v. 20(3), pp 1-38, mentioning these two species. But Maurice Kottelat, A.J. Whitten, S.N. Kartikasari and S. Wirjoatmodjo, in Freshwater fishes of Western Indonesia and Sulawesi, 1993, reckoned them separate genuine species in the wild. P. lateristriga is naturally found from Thailand and the
islands of Sumatra and Java to the western
drainages of Borneo, in clear mountain streams
strewn with rocks and boulders, often below
waterfalls. That habitat description should
suggest that the advice you generally hear,
which is to keep these fishes slightly on
the warm side, 76-84º, might be keeping
these fishes a little too warm. They'd appreciate
some extra current and plenty of surface
oxygen exchange. And though they'll school
loosely as youngsters, as they mature they
turn into solitary hiders. In their natural
habitat they can get to 18cm. (Puntius everetti remains a smaller fish, to 10cm.) Females
will fill with eggs after a year, but males
take about 18 months to reach sexual maturity.
My hunch is that when a closer look is taken, using DNA sequencing, any attempt at a consistent genetic distinction of captive breeding populations of these two species will evaporate. What's important to remember is that this little black and silver barb is a late-bloomer that might take 18 months to show the colors of sexual maturity. It will need a 36 inch tank when it reaches maturity, and it responds to regular water changes with improved colors. Puntius nigrofasciatus (Black Ruby Barb). Black Rubies originally came from Sri Lanka, where the IUCN "Red List," 1998, listed the species as "vulnerable." Sri Lankan law technically prohibits their export, but there isn't much official control. According to recent surveys though, P. nigrofasciatus is common enough, within its restricted natural habitats. And wild-collecting pressures are lower now, because all the Black Rubies you'll see on the market are captive-bred. According to a report and official recommendation made by Jonathan Mee and formerly posted among AgEnt documents at at www.agrolanka.org, Sri Lanka's fishes are collected by local village collectors, or casually farmed by farmers, who range from household groups up to the half-dozen big fish producers who control the export trade. Sri Lanka's fishes have been exported to Singapore, then re-exported. In the bare tank at your LFS, Black Ruby
Barbs are undistinguished-looking fishes
that will suffer from comparison with the
snappier Tiger Barbs in a nearby tank. Their
body color is less silvery, and their transverse
markings, blackish wedges with ragged edges,
are less crisp. (Nigrofasciatus means "black-banded.") Once you
have them settled and in good condition,
though, a transformation occurs. Now Black
Rubies will truly deserve their name: the
males' color at breeding time darkens to
a deep fiery cherry red overlaid with black,
with a bright cherry head. Competing males
display flank to flank and head to tail,
then start chasing each others' tails until
the two are spinning in the water, in an
action some biologists call "carouseling."
The breeding colors come and go with this
species-- a water change may spark them--
but even outside spawning time it's easy
to sex them: the slightly larger and more
robust females just have black bases to their
vertical fins, the males show a strong black
dorsal fin and a reddish tinge in their anal
fin. Puntius tetrazonus (Tiger Barb). This is the barb that's usually meant when someone just refers to their "Barbs." Tetrazonus does mean "four bands," just as you figured. P. tetrazonus has a natural range in Thailand and Malaya (with a sighting or two in Cambodia) and on Sumatra and in southern and eastern drainages of Borneo. So here's another freshwater fish (like some Bettas and Rasboras) with modern surviving populations that got separated when the sea level rose after the last Ice Age. During the glaciation, though South East Asia remained unglaciated and mild, so much of the earth's water was locked up in vast ice sheets, that the world's sea level dropped by many meters. The South China Sea drained away, exposing its vast flat continental shelf. That area became a gigantic savannah, with stretches of marshland and coastal peat forests linking what are now the islands of Sumatra and Java and Borneo to the Asian mainland. Chicago's Field Museum site offers maps that show you the expanded and linked-up river drainages in South-East Asia during the glacial maximums. Imagine the flat endless watery landscape of today's lower Mekong River and its delta, then expand it, if you can, to the scale of the Amazon basin. Starting about 8000 years ago, sea level began rising in fits and starts, and separate "relict" populations of many freshwater fishes became isolated on the large Indonesian islands. If this is interesting to you, you might like to see an article describing how populations of Arctic char got stranded in Ireland, becoming purely freshwater fishes, as the Glacial Age ended, at http://charrsoc.tripod.com/CurrentStatus/HowandWhy.htm In the wild, Tiger Barbs inhabit both clear and turbid shallow waters with a moderate rate of flow. In the 1980s wild P. tetrazonus were collected from swampy Malayan lakes with changable water levels and unexpectedly high carbonate levels. In captivity, optimal growth is at 72º-78°F, with breeding at 75º-82°F, the U.S. Department of Agriculture found, in the interesting document on techniques for breeding and raising Tiger Barbs from Hawaii's Center for Tropical and Sub-Tropical Aquaculture. The document was developed to help the nascent Hawaiian fish-farming industry, but it's got information that will be interesting to you, too. Tiger Barbs get a bad rap for fin-nipping and chasing slower fish, especially slow-moving ones with long-flowing fins like Gouramis. Keep them in a school, that's the first thing you'll hear about them. The fact is, Tiger Barbs form more of a pack than a school. Within the group there's lots of competition, which isn't limited to the males. As long as you have 8 or 9 Tiger Barbs together, they're completely occupied with keeping up their own standing with the others. A solo Tiger Barb, lonely and bored, looks for some stimulating mutual harassment, and the trouble starts. So keep your Tiger Barbs in a swarm. A stepped-up regimen of water changes will effect a change in these fishes: snouts glow cherry red, the males sport brilliant red in their fins, and silver scales take on golden tones. As Tiger Barbs age, more melanin gets deposited in their skin. Scales develop black edges that give them a netted look, and in certain lights their black markings iridesce with a green shimmer. This is called the Tyndall effect, from the physicist who first described how it works, and it results from scattering of shorter lightwaves-- the blue light-- by finely-scattered reflective particles that lie in the outer skin, above the dark layers of melanin pigment deeper in the dermis. Selected color varieties of Puntius tetrazonus are on the market. These are not a separate species, or hybrids of Puntius tetrazona with another Barb: they are mutations, in fact. There's an albino mutation-- isn't there always an albino version?-- which in the late 1990s began to be dipped in dyes in the Singapore fish mills to invent a spurious kind of "lavender barb." Aagh! Don't encourage this low practice by purchasing such tainted fishes. But a beautiful natural selection is the Mossy Green Barb that was developed by Singaporean breeders. Here for once is a domesticated selection that has a natural look, in which the fish produce so much extra melanin that the black bands have joined up. In a good example-- the only kind you should buy-- there isn't even a "saddle" of silver on the back; only the belly remains silver, and the snout, which darkens to cherry red when the fish are in glowing health. And as a result of the Tyndall effect I was telling you about, the black areas glisten with a strong green iridescence. These fishes would be spectacular displayed with well-conditioned Puntius nigrofasciatus. Puntius titteya (Cherry Barb). The Cherry Barb is a small barb (up to 2 in.) that might not be comfortable in the rowdier company of a mixed barb tank. It is gentler and more retiring than many and will choose the spots that are shaded by some floating plants. My very soft water and plenty of live blackworms keep them in spawning color. Male Cherry Barbs continually harass one another in barb fashion, but fins are never shredded. If your tank is less than 20 gallons and perhaps not as densely planted as it might be, usually it's the dominant male who will really be showing the glowing red for which you're keeping them. For each male Cherry Barb provide two or three of the less colorful females. But don't keep fewer than that. Cherry Barbs are omnivorous, constantly tasting the substrate with their delicate barbels. Like all barbs, Cherry Barbs will munch on your prized vegetation if you don't keep them constantly supplied with greens or green substitutes, like algae wafers. Puntius titteya was "Red Listed" as vulnerable by IUCN in 1998 and you keep hearing rumors that's it's extinct in its home waters. Kai Erik Witte said, "'Extinction' as announced by aquarium fish exporters usually translates into 'our local collector(s) don't catch them any more, or the numbers are too low to make enough profit'" at the Aquatic Conservation Network mailing-list, 30 Sept 1996. Apparently the Cherry Barb is still locally abundant in the very restricted habitats where it's found, in southwestern Sri Lanka; but only ten small localities were identified by Rohan Pethiyagoda in 1991. These are deep forest fishes, from shallow, clear, clean shaded forest pools and small waterways with gentle currents. Agricultural pollution and watershed despoliation are more threatening to them than collecting for aquarium trade export. Sri Lankan laws prohibit their export, not that any Sri Lankans would let that stand in their way, but fortunately all our stocks are now captive bred. Of the elegant small Sri Lankan Barbs headed for extinction, Puntius cumingi is the one I see least often on the market now. You'll find a link to a report about Sri Lanka's modest fish farming culture in the section about Barbus nigrofasciatus. Even if you don't take the pains to protect the eggs and raise the fry, Cherry Barbs are very willing to spawn for you. The night I wrote this I'd spent several hours watching two males and four females spawning in a densely-planted 10-gallon tank. Do the males drive the females, as male aquarists have always described it, or is it the females who test male vigor by leading them on? Feinting and dashing, the males follow closely through every twist and turn among the plants, rising from behind to nudge the females' vents. Together they dive through thick tangles of Java Moss and deposit eggs that are too small for me to see. Though the females eat eggs, the males are especially avid in hunting them down and eating them in the intervals between spawning runs, and the males take some moments out too for brief bouts of competitive sparring. In breeding dress they are suffused with strong cherry red, and their black lateral stripe fades. The ripe females show a tinge of red in every fin, but especially the anal fin, with its hairline black border, and their shining white bellies are prominent. Jacklyn McNaughton of the Regina Aquarium Society has bred these barbs. Her brief description is archived at http://www.cableregina.com/nonprofits/ras/ariticles/fish03.htm |