Fish biodiversity dynamics in the Western part of Lake Balkash (Central Asia)
-
1
Al-Farabi Kazakh National University, Kazakhstan
-
2
Kazakh Scientific Research Institute of Fisheries, Kazakhstan
-
3
Ile-Balkash Natural State Reserve, Kazakhstan
Lake Balkash is one of the biggest lakes of Central Asia and belongs to the Republic of Kazakhstan. The Ili River is the main water source of the lake. The delta of the river is the biggest wetlands of Central Asia. Indigenous fish fauna of the lake consisted of 9 resident fish species, and 2 more species were observed occasionally. More than 20 alien fish species had been introduced there during 1930-1960. It lead to the total extirpate of indigenous fish species. Since 1970th the delta of the Ili was considered as the main place of commercial fish reproduction. Soviet effective system of commercial fish protection was destroyed with crash of Soviet Union. At the same time, the number of people in the region increased significantly after migration from other regions of the country. It lead to the illegal fishery and high pollution of water resources. Investigation of fish community dynamics and an evaluation of the modern state of their diversity and population were the aims of our investigation. Fish sampling was provided according to special permission of local fishery authority with allowed gears (gill nets and drug nets, because electrofishing is strongly prohibited in the Republic of Kazakhstan). Biological and morphological analyzes of fish were performed by the routine method.
Sixteen alien fish species were found in the western part of Lake Balkash and the delta of the Ili River during 2017-2019 surveys. Asp Aspius aspius, Bream Abramis brama, Prussian carp Carassius gibelio, Common carp Cyprinus carpio, Grass carp Ctenopharyngodon idella, Silver carp Hypophthalmichthys molitrix, Roach Rutilus rutilus, Wels catfish Silurus glanis, Pike-perch Sander lucioperca, Volga perch Sander volgensis, and Amur snakehead Channa argus were commercial fish species. Non-commercial fish species were diverse and numerous and were presented by Amur false gudgeon Abbottina rivularis, Common sawbelly Hemiculter leucisculus, topmouth gudgeon Pseudorasbora parva, bitterling Rhodeus ocellatus, medaka Oryzias sinensis, beautiful sleeper Micropercops cinctus, and Amur goby Rhinogobius similis. Probably, Fringebarbel sturgeon Acipenser nudiventris and Aral barbel Luciobarbus brachycephalus still inhabited the delta. In addition, only a single specimen of indigenous Balkash perch Perca schrenkii was observed there. Many of commercial fish species were presented by adult specimens only. Compared to data obtained 40 years ago, drastic changes occurred in the structure of young fish community. At the end of the last century, Carp and Barbel juveniles dominated in the delta of the Ili River; juveniles of other commercial fish species were also numerous, juvenile Fringebarbel sturgeons were reported too. Currently, the non-commercial small fishes dominate in the delta. The growth rate of juveniles of commercial fish species is currently not significantly different from the growth rate in the last century. Large values of the asymmetry coefficient of bilateral signs indicate impaired homeostasis in the development of juvenile fish.
Acknowledgements
This work was supported by the Ministry of Education and Science of the Republic of Kazakhstan under grant No. AP05132792.
Keywords:
Lake Balkash,
Fish biodiversity,
fish population,
adult/juvenile fish ratio,
homeostasis of development
Conference:
XVI European Congress of Ichthyology, Lausanne, Switzerland, 2 Sep - 6 Sep, 2019.
Presentation Type:
Poster
Topic:
THREATS AND CONSERVATION
Citation:
Mamilov
N,
Shalakhmetova
T,
Amirbekova
F,
Adilbayev
Z and
Sutuyeva
L
(2019). Fish biodiversity dynamics in the Western part of Lake Balkash (Central Asia).
Front. Mar. Sci.
Conference Abstract:
XVI European Congress of Ichthyology.
doi: 10.3389/conf.fmars.2019.07.00145
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
14 Jun 2019;
Published Online:
14 Aug 2019.
*
Correspondence:
Mx. Leila Sutuyeva, Al-Farabi Kazakh National University, Almaty, 050040, Kazakhstan, s_leila_aktau@mail.ru