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Southeast Ecological Science Center
Aquarists in Japan, Europe, and, to a lesser extent, North America have kept snakeheads as pet fish. Because these fishes are predators (some growing quite large) and high costs are involved with providing preferred live food, few hobbyists become dedicated snakehead enthusiasts. Judging from questions asked in 2002 on various Internet chat rooms dealing with aquarium fishes in general and predatory species in particular, interest in snakeheads seemed to be concentrated among a small number of serious collectors and a slightly larger group of amateur aquarists curious about keeping predators as pets. Most questions appeared to originate from persons who had experience with cichlid fishes, were curious as to whether snakeheads could coexist with other fishes (particularly cichlids), and wanted to know how to maintain snakeheads, what to feed them, what species could be purchased, and where they could be bought. Experienced hobbyists typically cautioned that large aquaria are needed for several available species, that larger snakeheads were intolerant of other fishes and typically another of their own species, and warned of the expenses of providing live food.
Snakeheads that have been periodically available to hobbyists in the U.S. are listed in table 4. This information was assembled in 2002 from various Internet sites in the U.S. and Canada that represent retailers and hobbyist groups and should not be considered a complete “shopping list.” Moreover, availability
Table 4-Snakeheads of interest to aquarists in the U.S. - click to enlarge
Nevertheless, hobbyists, wholesalers, and retailers have been able to import snakeheads from many exporters in India and southeastern Asia that advertise on the Internet. Individual hobbyists occasionally advertised snakeheads for sale, whereas others inquired about availability on Internet aquarium fish “classifieds” and chat rooms; sometimes these ads or inquiries originated in states where possession of snakeheads is illegal.
Ng and Lim (1990) noted that smaller, colorful snakeheads are important in the aquarium fish trade in southeastern Asia. For example, they mentioned that Channa gachua was selling for S$30-60 per individual, and that slightly larger species such as C. melanoptera and C. pleurophthalma from Borneo, Sumatra, and Malaysia can garner prices as high as S$100 per fish. These fishes are caught wild, are primarily found in forest streams, and with deforestation occurring at a rapid pace, there is fear of overexploitation (Ng and Lim, 1990). In the U.S., prices for C. bleheri have ranged from $55-75 per individual for sizes of 8-15.5 cm specimens. Larger species of snakeheads can cost well over $100 per fish, depending on size, with young individuals of the same species fetching prices of $15 or more. Therefore, with their predatory nature, periodic availability, and relatively high prices for purchase and maintenance, snakeheads cannot be considered an important staple of the U.S. aquarium fish industry.
Because 14 states prohibited importation and possession of live snakeheads prior to the Federal ban on importation and interstate transport, the potential aquarium market for these fishes would appear to be limited. Nevertheless, there have been violations of these prohibitions in several states (“see section Regulations as of July 2002”).
Larger snakeheads can outgrow their aquaria and/or the interest of their owner(s). Some have been released, as witnessed by the capture of Channa micropeltes from the wild in waters of Maine, Maryland, Massachusetts, and Rhode Island (see section “Literature Review and Background Information, History of Introduction, Western Hemisphere”). Fortunately, this subtropical species cannot overwinter in these states.
Snakeheads have long been favored food fishes in India and many parts of Asia, particularly southeastern Asia (Lee and Ng, 1991). Some are utilized as luxury specialty foods, available alive in aquaria for customer selection at upscale restaurants in larger cities such as Calcutta, Bangkok, Singapore, Hong Kong, and other major locales. They also provide easily caught food for poorer people (Wee, 1982). These fishes are typically freshly killed, often cooked whole or prepared as filets or steaks, fried or steamed, or included in soups. Excess catches in Thailand and Cambodia are often dried for storage and future use (Wee, 1982; Balzer and others, 2002).
Lee and Ng (1991) noted that snakeheads can remain alive out of water for long periods of time if kept moist. They added that some people believed that this ability may have provided these fishes with healing properties, making them prized as food, particularly to people with illnesses or recovering from surgery. In such situations, the fish are killed just before cooking, the thinking being that healing properties are lost if the fish are killed sooner. They also mentioned that some people in Myanmar believed that one species of snakehead represented humans transformed into fish because of their sins, and that eating one would result in the consumer becoming a lion. Day (1875) noted that some people in India believed that snakeheads that suddenly appeared from mud in the bottom of dried ponds after monsoonal rains actually fell from the sky with the rains.
To illustrate the value of snakeheads in the Orient, Wee (1982) recorded 1977 market prices as $2.50/kg in Taiwan and $1.00/kg in Hong Kong. Ng and Lim (1990) reported prices of S$10 to S$20/kg for live Channa lucius, C. micropeltes, and C. striata, three of the larger snakeheads, in markets in Singapore in the late 1980s.
Asian food market in Nashville, Tennessee, showing tubs and aquaria containing
They commented that even smaller species (such as C. gachua and C. melasoma) are utilized as food in some parts of Asia (such as Myanmar and Sri Lanka), adding that C. gachua is sometimes used as bait to catch larger snakeheads. Peter Ng (personal commun., 2003) commented that C. gachua was sold alive in May 2000 in fish markets and restaurants in Xishuangbanna and Luxi, Yunnan Province, China, for about S$5/kg, and served in restaurants as whole fish soup. He also noted that C. marulioides was sold fresh and dry salted in Sambas and Sintang markets, western Kalimantan, in April 1998. He also saw C. marulioides being sold alive in November 1999 in Samarinda, east Kalimantan, and, in 2002, freshly sliced fillets of C. micropeltes were sold at S$20/kg in Singapore. In cities such as Hong Kong and Singapore, snakeheads are imported for food from Malaysia and Indonesia. This appears to have led to declines and scarcities of such species as C. striata in Malaysia where this fish is considered the most valuable and important snakehead in the nation as food and for medicinal purposes (Wan Ahmad, personal commun., 2001).
As noted earlier, some snakeheads, particularly Channa striata, called “haruan” in Malaysia, are important for medical use, particularly in Malaysia and Indonesia. Ng and Lim (1990) and Lee and Ng (1991) noted that C. lucius and C. micropeltes are also utilized for such purposes in both nations. Mention was made of use in a postnatal diet and during recuperation from illnesses or surgery (Lee and Ng, 1991). Although no specific information was given as to how the fishes were used following surgery, a neighbor of one of the authors (WRC), a Malaysian by birth, stated that the oils from the haruan are used to greatly reduce scarring following surgery, adding she had seen the results and scar tissue was dramatically reduced to a minimum. It has been demonstrated that haruan tissues contain substantial levels of arachidonic acid, a precursor of prostaglandin, essential amino acids (especially glycine), and polyunsaturated fatty acids required to promote prostaglandin synthesis, important factors in wound healing (Baie and Sheikh, 2000).
Channa striata is an important food fish throughout its native range (a species complex distributed from Pakistan eastward to southern China including Malaysia, Indonesia, and Java). Its supposed medicinal value doubtlessly explains why this species is often said to be the most widely introduced species of snakehead as persons of Asian origin emigrated to other locations. Channa maculata, often misidentified as C. striata, have been imported and released in a similar manner.
There is no evidence that any species of snakehead has been suggested for use as a biological control agent in the U.S. Nevertheless, certain species of snakeheads have been investigated or utilized as biological controls abroad. For example, Kehar and others (1995) reported experiments in which spotted snakeheads, Channa punctata, were used at different levels of pH and salinity in controlling mosquito larvae. They concluded that this snakehead could be utilized as a potential biological control of mosquito larvae in waters up to 10 ppm salinity. Mansuri and others (1979), however, determined that this species was intolerant of salinities above 6 ppm. Nevertheless, Khora and Rao
A more common use of snakeheads in biological control has been as a predator in fish culture. Conlu (1986) and Milstein and Prein (1993) reported that chevron snakeheads, Channa striata, are used to control overproduction of tilapias in culture ponds in the Philippines. Wee (1982) also noted this practice, adding, as did Bardach and others (1972), that they are also used in carp culture to control unwanted “pest fish” in culture ponds. In turn, snakeheads utilized in this manner are also sold as products of culture. Similarly, African snakeheads, Parachanna obscura, are used to control young of tilapias in aquaculture ponds in Bnin (Bonou and Teugels, 1985).
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