At that point in time, he described the local red drum market in Taiwan as “flooded”, with whole fresh fish selling at pond side for roughly $3.00 (US) per kg. Technical information on red drum culture was soon available locally, and in mainland China, for those interested in producing this fish.Ī representative of the Taiwan Fisheries Consultants group related the local status of red drum to me in several communications during early 1998. Dr Liao and his colleagues concluded that the species’ cold tolerance appeared suitable to allow winter survival under typical local conditions. These fish had been shipped to Taiwan as fry from Texas in 1991. In 1994 Dr I-Chiu Liao reported on the first successful spawning of red drum in Taiwan. Red drum's cold tolerance appeared suitable to allow winter survival under typical conditions in Taiwan In tropical locales such as Mauritius, there is little chance of escaped fish becoming established due to the requirement for a period of cold temperatures (< 16 o C) to trigger gamete maturation. Some examples include China, Ecuador, Guadeloupe, Israel, Martinique, Mayotte, Mauritius and Mexico. In contrast, successful commercial production of red drum has been firmly established in other parts of the world, with promising results to date. Nonetheless, several academic institutions – including Texas A&M University and Florida Atlantic University – continue to investigate methods to improve the profitability of red drum farming. The relative intolerance of red drum to cold temperatures was never solved, and R&D efforts in the US declined steadily through the 1990s as cold temperature intolerance, disease, cannibalism and cash flow risks were increasingly perceived to outweigh the potential for profits. During the late 1980s and early 1990s, catastrophic winter losses attributable to sudden or severe freezing temperatures occurred at several pioneering drum farming operations in the US. Parasitic infections and oxygen depletions often resulted in large losses, but on occasion yields were high (9,000 - 24,000 kg/ha), growth was acceptable (1.0 - 1.3 kg average weight at harvest) and survival was high (88.7 - 94.9 percent). In spite of these attributes, results of red drum grow-out studies in the US were highly variable. Additionally, once the first captive breeding stocks were established in comfortable hatchery settings, production of fertile eggs was fairly straightforward, as long as the fish could be chilled down to simulate winter conditions. Exceptionally good growth and survival were sometimes exhibited under culture conditions and the species grew well over a broad range of salinities. Red drum displayed exceptionally good growth and survival in culture conditionsĪpart from the prevailing supply and demand relationships at the time, a number of biological characteristics of red drum attracted the interest of researchers and culturists. As a result of overfishing, a subsequent moratorium on commercial harvests from the Gulf of Mexico led researchers and entrepreneurs to invest considerable resources in attempts to develop culture techniques for the species. Cold-related die-offs of juveniles in inshore habitats are common occurrences in wild populations, and similar cold-related losses are typical in outdoor culture ponds and tanks in temperate regions.Ĭonsumer interest in the red drum increased greatly in the US in the mid-1980s, largely as a result of the popularity of Cajun cuisine at the time. Gamete development and spawning are dependent on cold temperatures followed by gradual warming, but in spite of this the species is particularly vulnerable to sudden drops in temperature. The species occurs naturally in North America – from Veracruz, Mexico to as far north as Massachusetts. Red drum often live to 30 – 50 years of age and spawn annually after reaching maturity. The red drum ( Sciaenops ocellatus) is a marine species that spawns in nearshore areas, spends several years in coastal habitats, and then schools in offshore waters.
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