![]() ![]() ![]() However, it was later recognized that predation by Lates may not be solely responsible for the depletion of haplochromine stocks, and that the haplochromine stock was already affected by fisheries before the establishment of Lates, particularly by unregulated fishing or by trawling techniques introduced in the Tanzanian part of the lake. In the early 1980s this impact was considered an ecological and conservation disaster ( Coulter et al., 1986). Much has been said about the impact of the introduction of the Nile perch on the hundreds endemic haplochromines of Lake Victoria ( Lévêque, 1997). In Lake Biwa, the recent increases in numbers of the exotic bluegill Lepomis macrochirus, black-bass Micropterus salmoides, and Channa maculata, have been mirrored by serious declines in the native species Onchorhynchus rhodurus rhodurus (an endemic), Hemigrammocypris rasborella, and Hymenophysa curta. In Lake Titicaca the rainbow trout Salmo gairdneri was accused of seriously threatening the endemic Orestias fauna and for having been responsible for the disappearance of species such as Orestias cuvieri. In Lake Lanao, the introduction of the white goby ( Glossogobius giurus) in the early 1960s resulted in the elimination of numerous species of endemic cyprinid fish. ![]() The introduction of alien species has been considered as the main causes of extinction of endemic species flocks in several ancient lakes. The main goals of deliberate introductions by fishery officers were initially to improve sport fisheries and aquaculture, or to develop biological control of aquatic diseases, insects, and plants, or else to fill supposed ‘Vacant niches” and improve wild stocks in old or newly created impoundments. The introduction of alien fish into inland waters has occurred all around the world. Plain Water Formsįishes having minimum body modifications and insignificant migratory habits: Pisodonophis, Gudusia, Notopterus, Chitala, Amblypharyngodon, Aspidoparia, Catla, Cirrhinus, Cyprinus, Danio, Esomus, Labeo, Puntius, Rasbora, Salmophasia, Mystus, Sperata, Ompok, Wallago, Rita, Clupisoma, Eutropiichthys, Silonia, Pangasius, Clarias, Heteropneustes, Chaca, Xenentodon, Aplocheilus, Monopterus, Chanda, Nandus, Sicamugil, Rhinomugil, Anabas, Trichogaster, Glossogobius, Macrognathus, Mastacembelus, and Tetraodon.Ĭhristian Lévêque, in Encyclopedia of Biodiversity, 2001 V.C. Well-built fish having the power of overcoming adverse ecological conditions: Tenualosa, Barilius, Channa, Badis, etc. Semitorrential Formsįishes with less body modifications compared with rheophilic forms: Botia, Lepidocephalichthys, Acanthocobitis, Schistura, Canthophrys, Gagata, etc. In addition to the foregoing analyses, ecomorphologically ( Dey, 1973) the fishes of this region could further be categorized into four distinct groups as follows: True Hill-Stream or Rheophilic Formsįishes with strong body musculature and adapted to torrential abodes: Garra, Psilorhynchus, Balitora, Glyptothorax, etc. Species under this group include, among others, Megarasbora elanga, Botia dario, Lepidocephalichthys guntea, Glyptothorax telchitta, Parambassis baculis, Rhinomugil corsula, Sicamugil cascasia, and Tetraodon cutcutia. ![]() Incidentally, these ichthyospecies, in addition to being from this region, also occur in many other parts of India, Pakistan, Bangladesh, Sri Lanka, and Malaya. Genera-wise, the breakup under this group includes, among others, Esomus, Puntius, Rasbora, Ompok, Wallago, Clarias, Xenentodon, Channa, Glossogobius, Anabas, Macrognathus, and Mastacembelus. In addition to the above, on the basis of Indian and extra-Indian fish distribution ( Motwani et al., 1962), the ichthyospecies of this region could be significantly incorporated under the following two groups: Widely Distributed Species Genera-wise, the breakup under this group includes, among others, Gudusia, Tenualosa, Pisodonophis, Chanda, Xenentodon, Aplocheilus, Monopterus, Sicamugil, Rhinomugil, and Glossogobius. Devashish Kar, in Epizootic Ulcerative Fish Disease Syndrome, 2016 1.2.1.2 Peripheral Freshwater Fishes ![]()
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