I see alot of people talking about loaches and about breeding, here is a great article on them.
Clown loach (Botia macracanthus)
The clown loach, Botia macracanthus. Small specimens are important for the aquarium trade whilst large ones are sometimes sold for food. This is one of the most popular fishes in the trade
and is a clear Category I species. Juveniles are found in abundance in the large rivers of central Sumatra, west Kalimantan and central Kalimantan during the high water seasons. The adults breed at the beginning of the high water season and locals catch the young soon after. This is the only time in the year when the fish is caught. At other times, the individuals are too dispersed, scattered or large to be of value to the trade. The size range preferred by aquarists is three to eight centimetres. Larger specimens tend to be more carnivorous and do not fit in well in community tanks. Adults can attain sizes up to 40 centimetres long. The most commonly marketable size range is from two to four centimetres in length, with the optimum at around two cm. This is because it is at this size when most individuals are caught as they come downstream from their breeding grounds upriver. At this size, they are also easier to maintain in captivity and is easily fed with available fish feed.
The current trade in this species is estimated to be about 20 million pieces exported annually. According to a major dealer in Sumatra, handling up to one million pieces annually is common. It is important to note here that while the minimum breeding size of this fish is about 20-30 cm, the trade is only interested in much smaller individuals. As such, the fishes caught are basically juveniles, and breeding populations are left intact. This is possible also due to the current method for catching these fish (see later) which pre-select for the sizes to be caught. The breeding grounds are not yet known and even if discovered, it is unlikely that there will be any fisheries directed here as the individuals would be too large anyway. In any case, Indonesia has imposed a ban on the export of specimens larger than 10 cm in length. This ban, not only protects breeding adults, but also makes the captive breeding of this species by external agencies more difficult. Some dealers now culture clown loaches. Often, fishermen are able to trap individuals smaller than two cm. These are cheap and too small to be marketable but if they are grown out, a profit of up to 300% or more can be realised if a juvenile of 1.5 cm is raised to 3 cm. Juveniles exhibit incredible growth rates. A doubling in size is discernible in a week, if sufficient food, adequate aeration and filtration are provided. Some exporters also keep excess stock to grow out and sell later at higher prices when the fish is not in stock and prices are high.
Collection of Botia macracanthus is slightly different in Borneo and Sumatra. In Sumatra, Botia macracanthus are caught by using perforated bamboo poles stuck into the river bank substratum. The perforations are situated just below the nodes of the bamboo pole, and the size of the perforations will determine the occupant size. To obtain fish of a certain size range, the correct perforation size is made. This will catch fishes up to that size. The collector sticks these poles at regular intervals of about one metre apart in the river substratum. During the peak season, the collector will collect at regular intervals by lifting the whole pole out and pouring out the contents into containers or directly onto the boat's bottom, which is filled with water. Later, the catch will be sorted and transferred into holding tanks, before selling to a middle man. In Borneo, a variation of the abovementioned technique is used. A bundle of trimmed and split bamboo poles of a pre-selected diameter are tied together and sunk with stones. The bundle is attached with a rope that is tied onto stakes driven into the river substratum or onto overhanging bankside tree branches. Fish will take refuge in and amongst the bamboo poles. The collector lifts up the whole bundle and shake out the refugees into a container. This technique used is somewhat more stressful to the fish, as they are shaken out. The technique used in Sumatra only requires pouring out the contents, and thus less harm inflicted on the fish.
The clown loach has been heavily exploited in Sumatra and west Kalimantan for over 20 years now, but can still be found in good numbers in the wild. The reasons, as mentioned earlier is due mainly to the nature of the fisheries and the market, and to a lesser extent on government guidelines which controls its trade.
In Central Kalimantan, the exploitation of B. macracanthus is not as heavy and the locals catch adults for food (pers. comm., D. Siebert, BMNH). Specimens from Sumatra can be discerned from the Kalimantan specimens by the fish exporters. The overall colour is subtly different between the populations. The Sumatran specimens generally have a silvery sheen over the body; whereas the Kalimantan specimens have a more intense reddish colouration. This could however due to the habitat. The Sumatran specimens inhabits murky water rivers, whereas the Kalimantan ones prefer brown water rivers or even black water tributaries. The dissolved tannins and humic acids in black water tend to accentuate their reddish colours.
Captive artificial breeding of Botia macracanthus is possible and has been accomplished by the Thais. However, it is still not cost effective to captive breed them, with the wild caught stock being much cheaper. The species has some unusual breeding characteristics and it is not one of the easiest fish to breed in any case. The technology must be developed to be commercially viable, in order to take pressure off wild stocks. The trade must have enough foresight to counter the inevitable extirpation of wild stocks. If the technology has not been developed in advance, then the whole species may face extermination due to unscrupulous fishing methods, and more worrying, habitat destruction.
Clown loach (Botia macracanthus)
The clown loach, Botia macracanthus. Small specimens are important for the aquarium trade whilst large ones are sometimes sold for food. This is one of the most popular fishes in the trade
and is a clear Category I species. Juveniles are found in abundance in the large rivers of central Sumatra, west Kalimantan and central Kalimantan during the high water seasons. The adults breed at the beginning of the high water season and locals catch the young soon after. This is the only time in the year when the fish is caught. At other times, the individuals are too dispersed, scattered or large to be of value to the trade. The size range preferred by aquarists is three to eight centimetres. Larger specimens tend to be more carnivorous and do not fit in well in community tanks. Adults can attain sizes up to 40 centimetres long. The most commonly marketable size range is from two to four centimetres in length, with the optimum at around two cm. This is because it is at this size when most individuals are caught as they come downstream from their breeding grounds upriver. At this size, they are also easier to maintain in captivity and is easily fed with available fish feed.
The current trade in this species is estimated to be about 20 million pieces exported annually. According to a major dealer in Sumatra, handling up to one million pieces annually is common. It is important to note here that while the minimum breeding size of this fish is about 20-30 cm, the trade is only interested in much smaller individuals. As such, the fishes caught are basically juveniles, and breeding populations are left intact. This is possible also due to the current method for catching these fish (see later) which pre-select for the sizes to be caught. The breeding grounds are not yet known and even if discovered, it is unlikely that there will be any fisheries directed here as the individuals would be too large anyway. In any case, Indonesia has imposed a ban on the export of specimens larger than 10 cm in length. This ban, not only protects breeding adults, but also makes the captive breeding of this species by external agencies more difficult. Some dealers now culture clown loaches. Often, fishermen are able to trap individuals smaller than two cm. These are cheap and too small to be marketable but if they are grown out, a profit of up to 300% or more can be realised if a juvenile of 1.5 cm is raised to 3 cm. Juveniles exhibit incredible growth rates. A doubling in size is discernible in a week, if sufficient food, adequate aeration and filtration are provided. Some exporters also keep excess stock to grow out and sell later at higher prices when the fish is not in stock and prices are high.
Collection of Botia macracanthus is slightly different in Borneo and Sumatra. In Sumatra, Botia macracanthus are caught by using perforated bamboo poles stuck into the river bank substratum. The perforations are situated just below the nodes of the bamboo pole, and the size of the perforations will determine the occupant size. To obtain fish of a certain size range, the correct perforation size is made. This will catch fishes up to that size. The collector sticks these poles at regular intervals of about one metre apart in the river substratum. During the peak season, the collector will collect at regular intervals by lifting the whole pole out and pouring out the contents into containers or directly onto the boat's bottom, which is filled with water. Later, the catch will be sorted and transferred into holding tanks, before selling to a middle man. In Borneo, a variation of the abovementioned technique is used. A bundle of trimmed and split bamboo poles of a pre-selected diameter are tied together and sunk with stones. The bundle is attached with a rope that is tied onto stakes driven into the river substratum or onto overhanging bankside tree branches. Fish will take refuge in and amongst the bamboo poles. The collector lifts up the whole bundle and shake out the refugees into a container. This technique used is somewhat more stressful to the fish, as they are shaken out. The technique used in Sumatra only requires pouring out the contents, and thus less harm inflicted on the fish.
The clown loach has been heavily exploited in Sumatra and west Kalimantan for over 20 years now, but can still be found in good numbers in the wild. The reasons, as mentioned earlier is due mainly to the nature of the fisheries and the market, and to a lesser extent on government guidelines which controls its trade.
In Central Kalimantan, the exploitation of B. macracanthus is not as heavy and the locals catch adults for food (pers. comm., D. Siebert, BMNH). Specimens from Sumatra can be discerned from the Kalimantan specimens by the fish exporters. The overall colour is subtly different between the populations. The Sumatran specimens generally have a silvery sheen over the body; whereas the Kalimantan specimens have a more intense reddish colouration. This could however due to the habitat. The Sumatran specimens inhabits murky water rivers, whereas the Kalimantan ones prefer brown water rivers or even black water tributaries. The dissolved tannins and humic acids in black water tend to accentuate their reddish colours.
Captive artificial breeding of Botia macracanthus is possible and has been accomplished by the Thais. However, it is still not cost effective to captive breed them, with the wild caught stock being much cheaper. The species has some unusual breeding characteristics and it is not one of the easiest fish to breed in any case. The technology must be developed to be commercially viable, in order to take pressure off wild stocks. The trade must have enough foresight to counter the inevitable extirpation of wild stocks. If the technology has not been developed in advance, then the whole species may face extermination due to unscrupulous fishing methods, and more worrying, habitat destruction.
