The spread of weed fishes in fish farms Balkhash basin
In recent decades all over the world especially urgent became the problem of biological invasions, which are defined as all cases of penetration of living organisms into ecosystems situated beyond the original normal distribution. Invasive species are called invasive species or alien species can affect populations, species and communities of aboriginal and Ichtiofauna Flor, sacaste leading to irreversible changes in ecosystems.
The contamination of water bodies and fish farms unexpected species for the Balkhash-ili basin is also very important. Work on acclimatization of new fish species and the impact of faunal assemblages on the results of acclimatization are summarized in the summary of the “Fishes of Kazakhstan”, /1/. At this time, as a result of purposeful and unintentional introductions of fish fauna composition of the basin has more than tripled and now consists of 42 species /2/.
The results of the introduction of herbivorous fish in ponds and pond fish farms of the former Soviet republics led to a massive undesirable replenishment of local fish fauna low-value, non-target species of fish of the Chinese complex. The study of problems related to the spread of weed fish in water bodies of Kazakhstan, were held sporadically for more than 20 years ago /3,4,5,6,7/, but these studies have not been completed.
The aim of this work is vietnamesechristian, species and quantitative composition unplanned of invasive species in fish farms Balkhash basin.
MATERIALS AND METHODS
Materials for studies were collected from the following households:
1. Almaty pond farm is located on the river Ashybulak, the basin of Kaskelen. The farm has been breeding and commercial cultivation of common carp ( Cyprinus carpio ) in polyculture with phytovorous fish – white fish ( Hypophtalmihtix molitrix ), white Amur ( Ctenopharyngidon idella ).
2. Chilik pond farm is located on the bed of Lavar and R. Jars. This farm is also engaged in the breeding and rearing of carp in polyculture with herbivorous fish. At this time, the farm grows more valuable fish species: rainbow trout and paddlefish.
3. Kapchagai Presto the nursery farm is located on the left Bank of the Kapshagai water reservoir with water to the ponds directly from the reservoir through a pumping station. The farm is engaged in rearing of juveniles of carp and herbivorous fish, followed by the stocking of Kapchagay reservoir.
The material for these studies was the fees fish from pond farms of the Almaty region in 2006-2008 fishing was conducted in spring and summer, Malkov, close-meshed dragnet in the morning and afternoon hours. Fish were caught from nursery, feeding, Malkovich, uterine and repair ponds. Taxonomic identification of fish was conducted by the determinant of A. A. Baimbetov, C. R. Timirkhanov /8/. All captured fish were fixed in 4% formalin solution and processed in the laboratory by classical ichthyological methods /9/.
RESULTS AND DISCUSSION
In the studied fish farms were found 12 species of fish, which are among the weed, of which 7 species are unexpected invasive species: Amur chebachok ( Pseudorasbora parva ), OSTROBRAMSKA ( Hemiculter bleeker ), river abbotina ( Abbotina rivularis ), Chinese eleotris ( Micropercops cinctus ) ,bitterling ( Rhodeus serieceus ) and Chinese goby ( Rhinogobius similis ), Medak ( Oryzias latipes ). The remaining 5 species are native fish that do not have commercial value: spotted sloth ( Noemacheilus strauchi ), gray loach ( Noemacheilus dorsalis ), Severtsev loach ( Noemacheilus sewerzowi ), Semirechensk minnow ( Phoxinus brachyurus ). Currently, the distribution range of loaches and minnows, as fish species, is also declining /10/. In addition to these species in the catches were juveniles of commercial fish species such as pikeperch ( Sander lucioperca ), carp ( Carassius gibelio ), carp ( Cyprinus carpio ,) white Amur ( Ctenopharyngodon idella ), silver carp ( Hypophthalmichthys molitrix ).
All of the above unplanned acclimatizate constantly accompany the cultivation of farmed.
The table shows the species diversity and quantitative distribution of unplanned acclimatizants in all investigated fish farms of Almaty region. The results of the studies of numerous species in all investigated ponds are Amur chebachok and bull. Least in a proportion of met Chinese Medak and OSTROBRAMSKA. Members of aboriginal ichthyofauna met in small quantities in the catches from the fish ponds Chilik.
On nutrition of Amur chebachok refers to benthos feeders and is a competitor in the diet of valuable commercial fish, as in ponds and consumes feed. When lack of food the adult Amur chebachok can consume and larvae of carp /11/, Amur chebachok can be facultative parasite of herbivorous fish /12/.
The impact of other weed species to grow marketable fish has not been studied. Our results show that these species reach high numbers in fish farms Balkhash basin. Therefore, the study of weed impacts of alien fish species for aquaculture is an urgent task.
Table. Species diversity and quantitative structure of weed fish in pond farms of the Almaty region