The Composition and Status of Fish Species in the Current

Conditions of Tuzkan Lake

Dilora Dekhkonova

and Mukhayyo Atamuratova

Tashkent State Agrarian University, 100140, University Street 2, Qibray Area, Tashkent, Uzbekistan

Institute of Zoology of the Akademy of Sciences of the Republic of Uzbekistan,

100053, Bogishamol District, Tashkent, Uzbekistan

Keywords: Ichthyofauna, Tuzkan Lake, Pikeperch.

Abstract: In the article, the geographic location, physical-chemical condition, and ichthyofaunistic characteristics of

Lake Tuzkаn, identification of existing fish species using the detector. Biological characteristics of

representatives of Tuzkan lake ichthyofauna. The current composition of fish species in Lake Tuzkan, their

condition, the most common types of hunting importance, especially the plastic and meristic characteristics

of the pikeperch fish (Sander lucioperca L), analysis by classical and modern methods, the pikeperch fish

information on age size indicators is provided. The types and systematic status of the fish caught in the

conducted research hunts, as well as industrially caught by the fishing brigades, were taken and their

characteristics were determined using the available identifiers and the available identifier literature. Meristic

indicators of fish were determined by counting and measuring plastic indicators. Collection, processing, and

analysis of materials were carried out following generally accepted ichthyological methods. In the general

biological analysis of the fish, their total length (TL) was measured with an accuracy of 0.1 cm, and standard

length (SL) (to the point where the scales ended) was measured with an accuracy of 0.1 mm. The total body

weight (W, g) was measured to the nearest 1 gram, and the species of fish present in Lake Tuzkan were

determined.

1 INTRODUCTION

Supplying the population with food, preservation of

biodiversity and effective use of natural resources are

considered as the main problems in the world. In

order to effectively use water resources, special

attention is paid to the research work on increasing

the fish productivity of water bodies, including the

study of the species composition of hunting

ichthyofauna for fishing. Also, in a number of

developed European, North American, and Far

Eastern countries, existing fish species in water

bodies for recreational fishing are regularly

monitored.

Fishing and pasture aquaculture in inland water

bodies differ from the experience of developed

countries in other regions, including Uzbekistan, due

to differences in climate, location of water bodies,

physical and chemical characteristics, and also the

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composition of ichthyofauna is unique. Therefore, it

is necessary to carry out comprehensive research in

each area. To increase the volume of fishing in the

Tuzkan water basin, it is important to study the

existing species in the area and their current

ichthyofaunistic features in order to preserve

biodiversity..

The successful organization of fishing in natural

water bodies is closely related to the state of its

ichthyofauna and its population. Therefore, it is

important to determine the status of fish stocks in

natural water bodies and to conduct scientific

research on non-game fish and game fish, which

depend on biodiversity, ecological balance and the

survival of predatory fish. Obtaining information

about the current state of the number of species,

sexual maturity, and its reproduction is considered

one of the urgent tasks of research in the field of

ichthyology and fisheries (Dekhkonova, 2023).

Dekhkonova, D. and Atamuratova, M.

The Composition and Status of Fish Species in the Current Conditions of Tuzkan Lake.

DOI: 10.5220/0014242900004738

Paper published under CC license (CC BY-NC-ND 4.0)

In Proceedings of the 4th International Conference on Research of Agricultural and Food Technologies (I-CRAFT 2024), pages 197-200

ISBN: 978-989-758-773-3; ISSN: 3051-7710

197

Until 1969, Tuzkon Lake was brackish water with

a very high salinity (90 g/l) and dried up at the end of

summer due to the melting of snow and spring

rainwater. In 1969, Lake Tuzkon was connected to

Aydarkol through a narrow channel and was

constantly flooded. Today, the area of theLake

Tuzkon is 413 km

, its length is 34 km, and its water

volume is 1.07 km

(Dekhkonova, 2023). (Figure 1).

2 MATERIALS AND METHODS

Research work was carried out in Tuzakan Lake

during 2020-2022. The fish caught in the conducted

research hunts, as well as industrially caught by

fishing crews, were taken and their types were

identified using the existing identification and

identification literature and the monograph "Fishes of

Uzbekistan" (Yuldashov et al., 2018) by T.Salikhov,

M.Yuldashov, B.Kamilov using their characteristic

features. and clarifications were made to the

systematic situation (Salikhov et al., 2001). Meristic

characters of fish were determined by counting and

by measuring plastic characters (Pravdinб 1966).

Collection, processing and analysis of materials

were carried out in accordance with generally

accepted ichthyological methods. In the general

biological analysis of the fish, their total length (TL)

was measured with an accuracy of 0.1 cm, and

standard length (SL) (to the point where the scales

ended) was measured with an accuracy of 0.1 mm.

The total body weight (W, g) was measured to the

nearest 1 gram, and the species of fish present in

Tuzkan Lake were determined. (Table 1).

Figure 1: The geographical location of Tuzkan Lake[9].

Figure 2: Location of sampling sites in the Tuzkan Lake.

Research conducted in Tuzkan Lake revealed that

the only obligate predatory fish is pikeperch in this

water body. It was important to know the biological,

morpho-ecological characteristics of the pikeperch

fish in order to determine the reason why it can

survive in this water body. But since this study is very

large, we will mention some of them. A total of 190

pikeperch fish of different sizes were analyzed in

Tuzkon Lake. (table 2)

Table 1: The current state of fish species composition in

Tuzkan Lake.

№ Fish species

Tuz

kan

Lak

1. Roach fish - Rutilus aralensis Ber

. +

Common rudd - Scardinius

throphthalmus (L)

Grass carp – Ctenopharyngodon

idella (Val)

Aral asp fish – Aspius aspius

iblioides Kessle

Turkestan gudgeon – Gobio gobio

lepidolaemus K.

I-CRAFT 2024 - 4th International Conference on Research of Agricultural and Food Technologies

198

Samarkand Capoeta capoeta -

Varicorhinus capoeto heratensis st.

Aral shemaia – Chalcalburnus

chalcoides aralensis

8. Sabrefish

–

Pelecus cultratus L. +

Prussian carp –Carassius auratus

ibelio

10. Common carp

–

prinus ca

pio L +

11.

Silver carp - Hypophthalmichthys

molitrix

12.

Mosquito fish - Gambusia affinis

holbrookii (Jir)

13. Pikeperch - Sander lucioperca L +

14. Gob

fish - Neo

obius Jl

in +

Total 14

Table 2: The number of samples collected for the study of

pikeperch fish in Lake Tuzkon

№

Study of biological

characterist

Number

(pieces)

1 Morpholo

ic characteris

2 A

e of

row 100

3 sexual maturit

ndicators of fertility, the

size offish e

Total 190

The studied lake basin is quite large, and this lake

may have one or more populations of pikeperch fish.

This needs to be determined because it is a very

important aspect in managing the commercial fishing

of a fish species of important fishery value. For the

methodical solution of this problem, it is important to

give the classification of the pikeperch fish in each

water basin, to compare them with each other and

later with the data from other areas of the area where

the pikeperch fish is distributed (Dekhkonova, 2023).

The meristic characteristics of pikeperch fish were

determined by counting (Dekhkonova, 2022).

Table 3 shows the indicators of the meristic

characteristics of the group of pikeperch fish in this

lake.

Table 3.

Age

group

Back-calculated standard length

according age group, cm

pie

ces

23,

2 26

42,

24,

43,

53 18

28,

64,

70,

22,

38,

55 62

69,

26,

42,

53,

63.

75,

78,

Mean SLi

(cm)

44,

55,

66,

73,

78,

Annual

incremen

(cm/year)

20,

11,

10,

6,9 5,1

When analyzing the obtained meristic characters, it

was found that the most variable character is the

number of scales on the lateral lines. (Figure 4)

Table 4: Indexes of plastic morphological characteristics of

the pike perch in Tuzkon Lake (n - 40 speciments)

Morphological

characteristics

Min Max. Mean + S

Absolute length of

the fish, m

239 784 515,2±6,5

Standard length of

fish bod

, m

235 780 450±5,9

Total weight of fish

300 6030 1125,4±42

Lateral line 87 103 96,7±0,6

I D rays. s.

13 15 13,8±0,1

II D rays s.

2 3 2,2±0,1

II D rays b.

19 23 21,2±0,1

А rays. s.

2 3 2,5±0,1

А rays. b.

11 13 11,7±0,1

Gill rakers

64 198 121,0±0,1

Pyloric cecum

11 13 11,6±0,1

Figure 4: Variants formed by the number of scales on the

lateral line of the fish

The Composition and Status of Fish Species in the Current Conditions of Tuzkan Lake

199

Pikeperch fish is one of the important catchting

species, so they do not live to the state of natural

aging, that is, they are caught as a result of

commercial fishing. in the Tuzkon lake. The scales of

pikeperch fish uses as the main recording structure in

determining their age (Chugunova, 1959). (Table 4)

Table 4. The mean stanard length determined by

back-calculation method according to age groups of

the pike perch (males and females combined) (2020-

2022 y. 100 pieces)

The result of the obtained data can be analyzed

using the showing graph. (Fig. 5)

Figure 5: Growth rate of pikeperch fish in the Tuzkan Lake,

2020-2022 y

3 RESULTS AND DISCUSSION

We made an ichthyological analysis of the current

state of Tuzkan Lake. According to the results, 14

types of fish species were found in Lake Tuzkan, and

the composition of the species was clarified. In recent

years, the increase in the salinity level of Tuzkan

Lake and the receding of the water level and the

appearance of many islets did not fail to affect the

ichthyofauna in its composition, and therefore the

number of fish species in recent years decrease was

observed.

Research conducted in Lake Tuzkan revealed that

the only obligate predatory fish is the pikeperch fish

in this water basin. The length of the pikeperch fish

samples taken from Tuzkon Lake was 23.9-78.4 cm,

the total weight of the body was 300-6030 g. Fish up

to 6+ years old were found in the samples collected

from Tuzkon Lake. The samples collected from this

reservoir were composed of fish up to 6+. According

to the data presented in Table 4, the growth rate was

very high in the first year of life, and it was also high

in the second year. In the following years, it gradually

decreased

4 CONCLUSIONS

This can be concluded from the research results.

Continuous monitoring of the ichthyofauna is very

important for effective organization of fishing.

Analyzing the available fish species in Tuzkan Lake,

the common and only obligate predator species that is

important for hunting in this water body is the white

sla fish. According to the analysis of the results of the

conducted research, the pikeperch fish in Tuzkon lake

grows faster than in other water bodies where it

reproduces naturally (Makhmurov et al., 2024). It is

necessary not only to protect the species studied in

Tuzkan Lake, but also to develop ways of their

effective use.

REFERENCES

Chugunova N.I. Guide to studying the age and growth of

fish. Methodological manual on ichthyology - Moscow,

1959. - P.17--78.

Dekhkonova D.R Morpho-ecological characteristics of the

pikeperch (Sander lucioperca L) fish in the Aydar-

Arnasoy lake system. // Abstract of the dissertation

written for the degree of Doctor of Philosophy (PhD) in

Biological Sciences. - Tashkent. 2023. -5p..

Dekhkonova D.R. Morpho-ecological characteristics of the

pikeperch (Sander lucioperca L) fish in the Aydar-

Arnasoy lake system. // Dissertation written for

obtaining the degree of Doctor of Philosophy (PhD) in

Biological Sciences. - Tashkent. 2023. -14- 15b, 108b

Dekhkonova D.R, Sobirov J.J, Yuldashov M.A., Kamilov,

B.G., Biological characteristics of pike perch (Sander

lucioperca) from Aiydar-Arnasay lake system in middle

stream of syrdarya river in Uzbekistan // Egyptian

Journal of Aquatic Biology & Fisheries – Cairo, 2022 –

Vol. 26(6): – 1187 – 1197 (2022)

www.ejabf.journals.ekb.eg

Makhmurov I.B., Dekhqonova D.R. “Ichthyofauna of

Aydar-Arnasoy lake system and its importance in

fisheries” Uzbekiston agrar fani xabarnomasi 1/2(13)

Toshkent. 2024. – 124p

Pravdin I.F. Guide to the Study of Fish (Mainly

Freshwater). // 4th ed. - M.: Food Industry, 1966. - P.67-

69, 110-119, 110-222, 163-222, 269-371, 370-371.

Salikhov T.V., Kamilov B.G., Atadzhanov A.K. Fish of

Uzbekistan (determiner). // - Tashkent: ChinorENK,

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www.wikipedia.org

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TL, mm

Age

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