H. C. OKGERMAN, M. ELP, S. ATASAGUN

Turk J Biol 36 (2012) 125-134 © TÜBİTAK doi:10.3906/biy-1012-157

Th e growth and reproduction of white bream (Blicca bjoerkna L. 1758) in an oligo-mesotrophic lake in northwest Anatolia (Sapanca, Turkey)

Hacer Canan OKGERMAN1, Mahmut ELP2, Sibel ATASAGUN3 1Fisheries Faculty, İstanbul University, İstanbul - TURKEY 2Agriculture Faculty, Yüzüncü Yıl University, Campus, Van - TURKEY 3Hydrobiology Section, Biology Department, Ankara University, Ankara - TURKEY

Received: 09.12.2010

Abstract: Growth parameters and the reproduction period of white bream (Blicca bjoerkna L. 1758) sampled from Sapanca Lake were determined monthly between November 2000 and October 2001. Th ree hundred and fi ft y white bream specimens caught ranged in age from 1+ to 9+ years, and the majority of the samples consisted of individuals of the 5+-year-old age group. Th e von Bertalanff y equation was determined as Lt = 22.169 (1 – exp {–0.215[t + 0.986]}), Ø’: 2.02 for males and Lt = 31.917 (1 – exp {–0.122[t + 1.087]}), Ø’: 2.10 for females. Th e length-weight relationship was estimated as W = 0.0046 TL exp. 3.315 ± 0.002 for males (r2 = 0.9653, P < 0.05), and W = 0.0036 TL exp. 3.417 ± 0.002 for females (r2 = 0.9671, P < 0.05). Regression coeffi cients for sex were signifi cant (t-test, P < 0.05). Th e slope (b) signifi cantly diff ered (ANCOVA, P < 0.05) between months. Th e fact that the b values for male and female white breams diff ered from 3.0 indicates that there was positive allometric growth. Sex ratio was 1:1.36 (χ2; P < 0.05). Spawning period of white breams began at the end of April and continued until the beginning of July; water temperature during this period ranged between 13.7 and 28.5 °C.

Key words: White bream, Blicca bjoerkna L. 1758, Sapanca Lake, von Bertalanff y length-weight relationship, GSI

Kuzeybatı Anadolu’da oligo-mezotrofi k bir göldeki tahta balığının (Blicca bjoerkna L. 1758) büyümesi ve üremesi (Sapanca, Türkiye)

Özet: Kasım 2000 ve Ekim 2001 tarihleri arasında Sapanca Gölü’nden aylık olarak yakalanan tahta balığının (Blicca bjoerkna L., 1758) büyüme parametreleri ve üreme periyodu belirlenmiştir. Yakalanan 350 tahta balığının yaş değerleri 1+ ve 9+ arasındadır ve çoğunluğu 5+ yaşındaki bireylerden oluşmaktadır. von Bertalanff y büyüme eşitliği erkeklerde; Lt = 22,169 (1 – exp {–0,215[t + 0,986]}), Ø’: 2,02; ve dişilerde Lt = 31,917 (1 –exp {–0,122[t + 1,087]}), Ø’: 2,10 olarak belirlenmiştir. Boy ağırlık ilişkisi erkek bireyler için W = 0,0046 TL3,315 ± 0,002 ve dişiler için W = 0,0036 L3,417 ± 0,002 olarak hesaplanmıştır. Cinsiyetler arasındaki regresyon katsayısı önemlidir (t-test, P < 0,05). “b” değeri aylara göre önemli derecede farklılık göstermiştir (ANCOVA, P < 0,05). Dişi ve erkek tahta balıklarının “b” değeri 3’ten büyüktür ve pozitif allometrik büyüme göstermektedir. Cinsiyet oranı 1:1,36’dır (χ2; P < 0,05). Tahta balığının yumurtlama periyodu Nisan sonunda başlamakta ve Temmuz başına kadar devam etmektedir. Bu dönemdeki su sıcaklığı 13,7 ile 28,5 °C arasındadır.

Anahtar sözcükler: Tahta balığı, Blicca bjoerkna L. 1758, Sapanca Gölü, von Bertalanff y boy-ağırlık ilişkisi, GSI

125 Th e growth and reproduction of white bream (Blicca bjoerkna L. 1758) in an oligo-mesotrophic lake in northwest Anatolia (Sapanca, Turkey)

Introduction period in white bream from Sapanca Lake, an oligo- Fish constitute almost 50% of the total number mesotrophic lake in northwest Turkey. In addition, of recognized vertebrate . About 39% of these we compared the data obtained in this study with fi sh species are found in, or almost always found previously reported data in an eff ort to improve in, fresh water (1). White bream (Blicca bjoerkna L. our understanding of the growth parameters and 1758) spreads widely in inland waters and lagoons reproduction period in white bream in Sapanca Lake. of Marmara, Black Sea, , and Europe (2,3). White bream is euryphagous, with numerous Materials and methods populations inhabiting euthrophic waters (4). It inhabits the lower reaches of larger rivers in the Sapanca Lake is located in northwest Turkey bream zone, valley reservoirs, lakes, blind river arms, (40°41ʹN-40°44ʹN and 30°09ʹE-30°20ʹE). Th e surface and pools. Males of the species become partially area of the lake is 46.8 km2, mean and maximum mature as early as in the 2nd year, and females in the depths are 29 m and 52 m, respectively (Figure 1). 3rd-5th year. White bream can live up to 16 years (5). Th is lake is largely used for commercial and amateur Despite being an abundant species, white bream is of fi shing purposes as well as a source of drinking little importance as its meat is of poor quality, with water and industrial water. Th e littoral zone of the a great number of intermuscular bones. It forms an lake is dominated by Phragmites spp. Th ere are important component in the diet of predatory fi shes. some submerged macrophytes in the lake, such as White bream was zoogeographically introduced Chara spp., Myrophyllum spp., Ceratophyllum spp., into Turkey from the Western Th race region, and Potamogeton spp., Najas spp., and Nuphar spp. Th e it mainly spread in north and northwest parts of minimum and maximum temperature of the surface Anatolia (2). White bream (22.98%) is caught less water was 8 °C and 29 °C, respectively. Th e minimum in Sapanca Lake compared to rudd [Scardinius and maximum PO4-P, NO3-N, and Chlorophyll-a eryhthrophthalmus L. (24.43%)] and more compared values year round were 0.006-0.063 mg/L, 0.043- to vimba [Vimba vimba L. (8.71%) and roach 0.344 mg/L, and 7.97-21.59 mg/m3, respectively [Rutilus rutilus L. (21.71%)] (6). Although there is no (7). Sapanca Lake is changing from an oligotrophic economic value of white bream in general, it is now to oligo-mesotrophic state (8). Ten fi sh families caught for consumption in Sapanca Lake due to the were found in Lake Sapanca, namely Cobitidae, decrease of commercial fi sh as a result of overfi shing. , Atherinidae, Clupeidae, Gobiidae, Th e aim of the present study was to determine the Balitoridae, Esocidae, Salmonidae, Siluridae, and length-weight relationship, growth, and reproduction Syngnathidae (9,10).

SAPANCA LAKE 4 3 2 1

Figure 1. Sapanca Lake - sampling stations.

126 H. C. OKGERMAN, M. ELP, S. ATASAGUN

White breams were caught in Sapanca Lake was used to compare the parameters obtained from between November 2000 and October 2001 (at all grouped data (general coeffi cient) using the data monthly intervals). Since populations of white bream grouped by month (monthly coeffi cients). Condition were intensively caught at the eastern region of the coeffi cient (CF) was calculated for each sex using the lake according to the local fi shermen, these specimens equation CF = W/L3 × 100 (13). were sampled at 4 stations in this region of the lake Th e overall sex ratio was determined. Th e (Figure 1). All the fi sh specimens were caught using diff erence between sex ratios was tested using χ2 (chi gill nets of various mesh sizes (10, 22, 26, 30, 34, 38, 42, square) (16). Th e gonads were removed and weighed 48, 50 mm knot to knot). Th e study sample included to the nearest 0.1 g. Th e gonadosomatic index (GSI 350 white breams (202 males and 148 females). Fish %) (gonad weight/total body weight × 100) was were brought to the laboratory soon aft er capture. calculated for each fi sh and all values were averaged Th e total length (TL) of each fi sh was measured in on a monthly basis (13). In each sampling month, the laboratory (to the nearest 0.1 cm) and the fi sh water temperature was measured to determine the were weighed in grams (to the nearest 0.1 g). Th e sex relationship between temperature and gonad growth. of the specimens was determined by macroscopic Statistical analyses were carried out using SPPS for and microscopic observation of the gonads. Scales Windows V 11.0 and Statistica 6. on the left side of the body between the lateral line and dorsal fi n were collected and analyzed between 2 slides in order to determine age (11). Scales of 6 Results and discussion individuals out of the 350 were deformed, and not Female and male white breams ranged in age used for assessment. groups from 1+ to 9+ years (excluding 2+); the 5+ Growth was investigated by applying the von year-old age group was the most abundant (36.04%). Bertalanff y growth function to pooled size-at-age for Total length ranged from 6.6 to 24.3 cm and weight both sexes using standard non-linear optimization ranged from 2.8 to 159.4 g (Table 1). Th e diff erence methods. Th e von Bertalanff y growth function was in growth between male and female white breams calculated as follows: Lt = L∞ (1 – exp {–K[t – to]}), was signifi cant (P < 0.05). Body size calculations where Lt is length at age t, L∞ is asymptotic length, k made according to sex and age showed that male + + is the growth coeffi cient, and to is the hypothetical age white breams in the age groups 1 and 3 were longer at which length is equal to zero (12-14). Th e growth compared to females of the same age groups (Table performance index (Ø’) was calculated using the 1). Female individuals in the same age groups except + equation Ø’= log10(K) + 2log10(L∞) (15). age group 1 were found to be heavier than the male Th e relationship between the length (L) and weight individuals. Diff erences in length and weight between (W) of a fi sh is usually expressed by the equation W the male and female white breams were signifi cant in + + + = aLb, a and b, the coeffi cient of determination (r2) the 5 , 6 , and 7 year-old age groups (P < 0.05) (Table and the standard errors (S.E.) were estimated over 1). the entire study period by least squares regression Th e average condition value of male white breams using the log transformed weights and sizes. In order was 1.121 ± 0.008, while the average condition value to confi rm whether b-values obtained in the linear of female white breams was 1.179 ± 0.012, and the regressions were signifi cantly diff erent from the diff erence between the sexes was signifi cant (P < isometric values, we used the t-test with a confi dence 0.05, t-test, Table 1). Condition value of female level of ±95% (α = 0.05) (16). Additionally, the t-test white breams was higher than that of male white was used to compare regression lines between the breams (except age group 1+) (Table 1). In addition, sexes and to test the signifi cance of the diff erences the condition values for males and females were between slopes (b) and intercepts (a) (17). When seasonally assessed (Figure 2). Th e condition value testing the diff erences between months, analysis of of the females was at the maximum level in April covariance (ANCOVA) was used to compare the (1.330 ± 0.026), while the condition value of males white bream regression slopes (17). Student’s t-test was highest in March (1.221 ± 0.010) (Figure 2).

127 Th e growth and reproduction of white bream (Blicca bjoerkna L. 1758) in an oligo-mesotrophic lake in northwest Anatolia (Sapanca, Turkey) *** ), males P = 0.05 ** P = 0.05 Blicca bjoerkna * p<0.05 p<0.05 p<0.05 P>0.05 P>0.05 P>0.05 P > 0.05 P > 0.05 P < 0.05 P > 0.05 P > 0.05 P > 0.05 P < 0.05 P < 0.05 P < 0.05 P < 0.05 P < 0.05 P < 0.05 P > 0.05 P > 0.05 P > 0.05 P = 0.05 (female) (min-max) CF ± SE 1.211 ± 0.029 1.060 ± 0.022 1.106 ± 0.024 1.184 ± 0.017 1.207 ± 0.021 1.330 ± 0.039 1.009 ± 0.035 (1.181-1.268) (0.914-1.181) (0.863-1.296) (0.918-1.417) (0.884-1.489) (1.086-1.548) (0.974-1.045) erent age groups of white bream ( bream white of groups age erent female) 23.32-1.02 3.35 ± 0.55 (2.80-3.90) (min-max) 39.23 ± 3.47 58.28 ± 3.15 70.02 ± 3.67 W ± SE( 109.73 ± 8.91 (81.20-136.3) (18.90-30.80) (18.70-83.40) (19.60-146.6) (35.80-123.0) (58.20-158.4) 110.00 ± 15.96 (female) 6.90 ± 0.30 (6.60-7.20) (min-max) 20.77 ± 1.04 12.99 ± 0.22 14.96 ± 0.36 16.73 ± 0.23 17.80 ± 0.25 20.01 ± 0.53 (19.0-22.60) TL ± SE (11.90-14.70) (12.30-18.60) (12.60-22.30) (14.80-20.90) (17.20-24.30) 3 1 23.20 159.40 1.277 N 13 25 54 33 15 (male) cance level, min –max: minimum and maximum values maximum and min –max: minimum level, cance (min-max) CF ± SE 0.968 ± 0.015 1.080 ± 0.023 1.113 ± 0.014 1.148 ± 0.014 1.169 ± 0.018 1.151 ± 0.037 (0.906-1.016) (0.824-1.312) (0.904-1.494) (0.904-1.494) (0.989-1.309) (1.081-1.209) (male) ), values of P; signifi P; of ), values (18.2-25.0) (min-max) W ± SE 22.04 ± 0.87 34.53 ± 2.88 47.40 ± 1.73 58.38 ± 1.72 66.86 ± 3.86 83.97 ± 4.78 (26.0-106.6) (12.90-91.40) (21.50-84.90) (37.30-110.0) (75.30-91.80) Blicca bjoerkna (male) (min-max) TL ± SE 13.14 ± 0.15 14.46 ± 0.31 16.03 ± 0.15 17.10 ± 0.15 17.75 ± 0.29 19.40 ± 0.58 (12.30-13.50) (10.90-19.10) (13.20-19.40) (13.70-20.50) (15.20-20.60) (18.40-20.40) and females, caught in Sapanca Lake in 2000 and 2001. Lake in 2000 and in Sapanca caught females, and - 1 7.607 4.60 1.048 2 3 cance values belong to CF values to belong values cance 30 70 66 21 cance values belong to W values to belong values cance cance values belong to TL values to belong values cance + + + + + + + + + 9 4 5 6 7 3 2 8 1 Age N N: number of white bream ( bream white of N: number *Signifi **Signifi ***Signifi Table 1. Table diff for (SE) error (CF), standard factor condition g), mean (W, weight mean (TL, cm), and length total Mean

128 H. C. OKGERMAN, M. ELP, S. ATASAGUN

1.6 Blicca bjoerkna 25 n :202 Male Blicca bjoerkna 1.4 male Female nfemale :148 20 nmale :198 1.2 nfemale :146 1 15 0.8 0.6 10 Total length (cm) 0.4 Ltmale = 22.169 (1 - exp{-0.215[t + 0.986]}) Condition factor (CF%) 5 Ltfemale = 31.917 (1 - exp{-0.122[t + 1.087]}) 0.2

0 0 123456789 July 01 April 01 May 01June 01 Age (years) March 01 August 01 JanuaryFebruary 01 01 October 01 NovemberDecember 00 00 Months September 01 Figure 3. Age-length relationships in females and males of white Figure 2. Monthly condition fac tor (CF%) variation in white bream (Blicca bjoerkna L.) caught in Sapanca Lake in bream (Blicca bjoerkna L.) caught in Sapanca Lake in 2000 and 2001. 2000 and 2001, n: number of white breams. Th e slope (b) diff ered signifi cantly (ANCOVA, P < 0.05) with respect to the time of the month for Th e observed age–length data and the fi tted white bream. LWR curves of the samples are shown von Bertalanff y curve are presented for each sex in in Figure 4a,b. Th e general coeffi cient of allometry Figure 3. Th e von Bertalanff y growth equations were was 3.3901. Th e diff erences between the general estimated as Lt = 22.169 (1 – exp {–0.215[t + 0.986]}) coeffi cient of allometry (all data) and the monthly for males and Lt = 31.917 (1 – exp {–0.122[t + 1.087]}) coeffi cients were signifi cant (95% CL) for all months for females (Figure 3). Th e growth performance index analyzed (Table 2). (Ø’) was 2.02 for males and 2.10 for females. Th e overall sex ratio of males to females was Th e estimated length-weight relationship (LWR) 1:1.36, and χ2 (chi-square) analysis showed that there was W = 0.046 L3.315 ± 0.002 (r2 = 0.9653, N = 202, P was a signifi cant diff erence from the expected ratio < 0.05) for males and W = 0.0036 L3.417 ± 0.002 (r2 = of 1:1 (P < 0.05). Gonad development, determined 0.9671, N = 148, P < 0.05) for females. Th e regression by the gonadosomatic index (GSI%), was at its coeffi cient for sex was signifi cant (t-test, P < 0.05). maximum for males in March (10.722 ± 0.496) and

250 120

100 Blicca bjoerkna 200 Blicca bjoerkna 3.417±0.002 3.315±0.002 W(female) = 0.0036 L W(male) = 0.0046 L 80 2 R2 = 0.9671 R = 0.9653 150 N: 202 N: 148 60

Weight (g) 100 Weight (g) 40

50 20 a b

0 0 0 5 10 15 20 25 0 10 20 30 Total length (cm) Total length (cm) Figure 4. Length-weight relationships [male (a) and female (b)] of white bream (Blicca bjoerkna L.) in Sapanca Lake in 2000 and 2001, N: number of white breams.

129 Th e growth and reproduction of white bream (Blicca bjoerkna L. 1758) in an oligo-mesotrophic lake in northwest Anatolia (Sapanca, Turkey)

Table 2. Length-weight relationships of white breams (Blicca bjoerkna L.) for each month and also for the whole year in Sapanca Lake.

2 Months n TL (cm) a b SE (b) 95% CI r P Growth type November 2000 3 17.5-23.2 0.0009 3.8508* 0.012 0.023 0.987 < Allometric (+)

February 2001 7 13.4-19.9 0.0061 3.2410* 0.0067 0.013 0.988 < Allometric (+)

March 2001 28 12.7-20.8 0.0061 3.2474* 0.0046 0.004 0.964 < Allometric (+)

April 2001 120 12.4-24.3 0.0033 3.4485* 0.0022 0.004 0.964 < Allometric (+)

May 2001 91 10.9-19.8 0.0053 3.2486* 0.0034 0.006 0.949 < Allometric (+)

June 2001 52 11.9-16.9 0.0130 2.9127* 0.0046 0.009 0.894 < Allometric (-)

July 2001 10 6.6-20.6 0.0074 3.1562* 0.0078 0.015 0.997 < Allometric (+)

August 2001 12 15.1-22.6 0.0203 2.8153* 0.0041 0.008 0.979 < Allometric (-)

September 2001 17 16.1-22.3 0.0109 3.0223* 0.0066 0.012 0.909 < Isometric

October 2001 10 16.3-20.0 0.0314 2.6352* 0.0108 0.021 0.810 < Allometric (-)

General 350 6.6-24.3 0.0038 3.3901 0.0018 0.003 0.965 < Allometric (+) n: number of individuals; TL: Total length, cm (Length range); a: a coeffi cient related to body form; b: allometric coeffi cient; SE (b): 2 Standard error of b; IC % 95: Confi dence level of b (α = 0.05); r : Determination coeffi cient; * : P < 0.01: Student’s t-tests for diff erences between allometry coeffi cient (b) of monthly and yearly data set. for females in April (15.857 ± 1.491) (Figure 5). Th e Th e exponents of the estimated LWR for male GSI increased in females in February and peaked and female white breams in Sapanca Lake exhibited in April, and gradually declined in early July. Th e positive allometry (bmale: 3.315 ± 0.002; bfemale: 3.417 temperature during the white bream reproduction ± 0.002), and signifi cantly diff ered in sexes (t-test, P period ranged between 13.7 °C and 28.5 °C (April- < 0.05) and months (ANCOVA, P < 0.05). Th e value July). of “b” in Manyas Lake was 3.24 for male and 3.27 for female white breams (18). In Balaton Lake and

30 Berounka River the values of “b” were determined Blicca bjoerkna as 3.267 and 3.328 for whole white breams, 25 nmale: 202 respectively (19,20). Th e reproduction process 20 nfemale: 148 (spawning and gonad activity) and changes in food 15 uptake could cause monthly variations in length-

GSI%; ºC weight relationship parameters (21). Th e diff erences 10 GSI%-male GSI%-female between all the monthly coeffi cients were signifi cant 5 Temperature (°C) (95% CL). Th e b value was at its lowest level in 0 August (2.8153 ± 0.0041) and highest in November (3.8508 ± 0.012). Th is result was most probably April 01 June 01 July 01 March 01 May 01 August 01 JanuaryFebruary 01 01 October 01 because of the scarcity or abundance of food, and NovemberDecember 00 00 September 01 Months the small number of specimens in these months. Figure 5. Relationship between gonadosomatic index (GSI) Th e reproduction process (spawning and gonadal variation and temperature (°C) in white bream (Blicca bjoerkna L.) caught in Sapanca Lake for each month activity in June) and changes in food uptake, or fewer in Sapanca Lake in 2000 and 2001, n: number of white individuals (in August and October) could cause breams. negative allometry in the length-weight relationship

130 H. C. OKGERMAN, M. ELP, S. ATASAGUN

parameters. Furthermore, the diff erences in b values length (L∞) was higher than expected because the may have been due to the infl uence of water quality individual in question (9+) had a mean length value or food availability on fi sh growth (22), diff erences in greater than that of the previous age group (8+). On sampling, the number of specimens, length range of the other hand, the estimated growth rate (k), which the species (23), eff ect of diff erent areas, sex, stomach is generally inversely correlated with L∞, was higher fullness, age, health, or preservation techniques (24- in females than in males (Table 4). Th e to values 26). obtained for male and female white breams were very negative in the present study, as compared to White breams over 9+ years of age were not those obtained at other localities (Table 4). Th e high observed (Table 3), apart from the 11+-year-old white t values may be attributed to the lack of young-of-the breams caught in the Kremenchug Reservoir (27). o year specimens. Th e diff erences in growth of white Th e growth rate for length in the present study was bream between localities might have been because relatively low in comparison with that in populations Sapanca Lake is south of those other localities, from other regions (Table 3). insuffi cient food supply in food habitats, diff erences When compared with the von Bertalanff y growth in water temperature, competition for food between equations in the literature, the growth of white white bream and the other cyprinid species with very bream in Sapanca Lake was lower than those in similar feeding habits, and diff erences in the stage Manyas Lake and Berounka River, with rather high of ontogenetic development of white bream, such as k value and growth performance index (Ø’) (Table condition, length, age, sex, and gonadal development 4). In accordance with the sexual dimorphism in (13). size mentioned previously, estimated asymptotic Th e reproduction season of white bream in length (L∞) of female white breams was higher than Sapanca Lake began at the end of April and extended that of males. Th e estimated asymptotic length for to the beginning of July, with maximum gonadal females was much greater in comparison with the activity in June (Figure 5). Water temperature is size of the largest male in the study. We think that the principal environmental factor aff ecting the the reason for this was that only one individual of the reproduction of fi sh. During the reproduction 9+ age group was eff ectively sampled. Th e asymptotic period water temperature was 3.7 °C (April), 18.7

Table 3. Mean length (TL, cm) according to age of white bream (Blicca bjoerkna L.) at diff erent localities as well as Sapanca Lake, N: number of white bream.

Age R. Localities Sex N 1+ 2+ 3+ 4+ 5+ 6+ 7+ 8+ 9+ M 59 6.4 8.45 12.8 ------18 Manyas Laked (FL) F 167 6.7 9.73 11.67 14.35 ----- 19 Balaton Lakec (SL) WS 127 8.4 10.9 13.0 15.0 16.8 18.8 20.5 22.0 - M 98 - 10.6 13.4 15.6 17.9 20.4 21.1 23.1 23.0 27 Kremenchug Reservoira (SL) F 152 - 11.2 14.4 17.9 20.4 23.7 24.8 26.8 28.7 28 Neusiedlerseeb (TL) WS 5.2 7.7 9.7 11.6 ----- 29 Dnieper Rivera (SL) WS - 5.25 8.65 11.76 15.1 18.1 20.3 23.1 24.5 -

Sapanca Laked (TL) M 198 7.6 - 13.1 14.4 16.0 17.1 17.7 19.4 - (present study) F 146 6.9 - 12.9 14.9 16.7 17.8 20.0 20.7 23.2

R: References; a: UKRAINE; b: AUSTRIA; c: HUNGARY; d: TURKEY; M: Male; F: Female; WS: Whole samples; FL: Fork Length; TL: Total Length; SL: Standard Length

131 Th e growth and reproduction of white bream (Blicca bjoerkna L. 1758) in an oligo-mesotrophic lake in northwest Anatolia (Sapanca, Turkey)

Table 4. Von Bertalanff y growth parameters and derived index of growth performance (Ø’) for the studied white bream (Blicca bjoerkna L.) population.

a b c d L∞ (cm) k to Ø’ Localities References 18.92 (FL) 0.374 -0.248 Manyas Lake (Turkey) 18

35.90 (SL) 0.098 -0.64 2.10 Balaton Lake (Hungary) 19

23.40 (SL) 0.270 -0.27 2.17 Berounka River (Czech Rep.) 20

30.98 (FL) 0.110 2.02 Gorkovsky Reservoir 30

22.2* (TL) 0.215 -0.986 2.02 Sapanca Lake (Turkey) Present study 31.9** (TL) 0.122 -1.087 2.10

* : Male; ** Female; a: the asymptotic length; b: the growth coeffi cient; c: the hypothetical length at zero age d : growth characteristic in terms of length; FL: Fork Length; TL: Total Length; SL: Standard Length

°C (May), 23.9 °C (June), and 28.5 °C (July). Th e waters of Finland, and the UK when compared with results indicate that reproduction in Sapanca Lake white bream populations in other regions (Table is concentrated in a rather long period. Th e white 5). Th e beginning and ending dates of spawning bream in Sapanca Lake reached sexual maturity at may vary due to diff erent ecological and climatic 3+ (14.7 cm TL) and 4+ (18.6 cm TL) years of age conditions. Th e spawning period of fi sh may be (31). Th e gonadal maturity age of white bream in inland waters of Finland was also 3+ and 4+ age (32). aff ected by altitude, temperature, and food quality Th e reproduction period of fi sh in Sapanca Lake as well as ecological factors, such as stagnant water is broadly similar to that in Manyas Lake, inland and running water (37).

Table 5. Reproduction season according to gonadosomatic index (GSI) value of white bream (Blicca bjoerkna L.) in diff erent localities and Sapanca Lake.

Reproduction season T. °C Localities References

From mid-April to beginning of June 21-24 Manyas L. (Turkey) 18

In May - Neusiedlersee (Austria) 28

In May 15-18 Dnieper R. (Ukraine) 29

In May, June, and July - In Finland 32

In late May and June >16 Ilmen L. (North Russia) 33

In May and June 16-25 In France (R.) 34

In May, June, and July 15 In UK 35

In May and June - Schleswig-Holstein R. (Germany) 36

From late April and beginning of July 13.7-28.5 Sapanca L. (Turkey) Present study

T: Temperature; D.L.: Dam Lake; S: Stream; R: River; L: Lake

132 H. C. OKGERMAN, M. ELP, S. ATASAGUN

Consequently, the growth of fi sh is getting slower Acknowledgements with age in Sapanca Lake compared to other localities. Th is work was supported by the Research Fund of Moreover, the growth of Vimba vimba L. was reported İstanbul University. Project number: T-957/0611200. as slower, compared to other localities, in Sapanca Lake (38). Th e cause of this situation is thought to I am grateful for support of the Research Fund of be related to ecological factors and, particularly, diet İstanbul University, Nizamettin Şahin, and Adnan overlap among these species with relative abundance Sümer. of cyprinid species. Th erefore, there is a need for the purpose of detecting relative abundance and food habits of white bream and other cyprinids in Sapanca Corresponding author: Lake. However, we suggest that fi shing in the lake Hacer Canan OKGERMAN be prohibited from April to July in order to ensure maximum productivity of the white bream population. Fisheries Faculty, In order to ensure the continuity of a sustainable stock İstanbul University, white bream in Sapanca Lake, the minimum catch İstanbul - TURKEY length for fi sh should be more than 19 cm (TL) and 5+ years should be the minimum age. E-mail: [email protected];

References

1. Cengiz Eİ, Ünlü E, Başhan M. Fatty acid composition of total 10. Rahe R, Worthmann H. Marmara Region Internal Fishery lipids in muscle tissues of nine freshwater fi sh from the River Products Development Project. PN 78- 2032.7, Eschborn; Tigris (Turkey). Turk J Biol 34: 433-8, 2010. 1986. 2. Geldiay R, Balik S. Freshwater fi sh in Turkey. Ege Univ Science 11. Lagler KF. Freshwater Fishery Biology. W. M. C. Brown Fac Book Series 97: 1988: pp. 310-312. Company, Dubuque, IA; 1966. 3. Froese R, Pauly D. Fishbase (www database). World wide Web 12. Von Bertalanff y L. Quantitative laws in metabolism and Electronic Publication. URL: http://www.fi shbase.org , 2010. growth. Q Rev Biol 32: 217-231, 1938. 4. Lammens E H R R. 1989. Causes and consequences of the 13. Ricker WE. Computation and interpretation of biological success of bream in Dutch eutrophic lakes. Hydrobiol Bull 23: statistics of fi sh populations. Bull Fish Res Board Can; 1975. 11-18, 1989. 14. Sparre P, Venema SC. Intoduction to tropical fi sh stock 5. Pecl K. Th e Illustrated Guide to Fishes of Lakes and Rivers. assessment. Part 1. Manual. FAO, Rome; 1992. Printed in Czechoslovakia by Svoboda; 1990. 15. Pauly D, Munro JL. Once more on the comparison of growth in 6. Karabatak M, Okgerman H. A preliminary study on the fi sh and invertebrates. ICLARM Fishbyte 1: 21-22, 1984. composition, population abundance and length distribution of 16. Sokal R, Rohlf FJ. Introduction to Biostatistics. Second ed. economic fi sh species in the lake Sapanca, Turkey. Journal of Freeman, New York; 1987. Fisheries & Aquatic Sciences 13: 81-88, 2002. 17. Zar JH. Biostatistical analysis, third ed. Prentice-Hall, 7. Yılmaz N. Phytoplankton Synthesis in Sapanca Lake Surface Englewood Cliff s, NJ; 1996. Water, Th e Seasonal Examination of the Density and Chlorophyll-a Content. MSc thesis. İstanbul University Natural 18. Balik S, Ustaoğlu MR, Sarı HM. Investigations on Growth and Sciences Institute. İstanbul; 2002. Reproduction Characteristics of White Bream (Blicca bjoerkna, L., 1758) Population in Lake Kuş (Bandırma). Journal of 8. Aykulu A, Albay M, Akçaalan R et al. Species composition, Fisheries and Aquatic Sciences. Special Issue: 223-231, 1999. abundance and seasonality of phytoplankton in a moderately deep Turkish Lake. Nova Hedwigia, Beiheft 130: 325-38, 2006. 19. Specziár A, Tölg L, Bíró P. Feeding strategy and growth of cyprinids in the littoral zone of Lake Balaton. Journal of Fish 9. Numann W. Researches on Limnological and Fishing Science Biology 51: 1109-24, 1997. in Diff erent Lakes in Anatolia and a Particular Study on Carps Living in Th ose Lakes. İstanbul University Faculty of Science 20. Hanel L. Growth of four cyprinid fi shes in the river Berounka Hydrobiology Researches Institute Publications Monography (Central Bohemia). Zivoc Vyr 36: 929-37, 1991. 7, İstanbul; 1958.

133 Th e growth and reproduction of white bream (Blicca bjoerkna L. 1758) in an oligo-mesotrophic lake in northwest Anatolia (Sapanca, Turkey)

21. Andrade HA, Campos RO. Allometry coeffi cient variations of 30. Ilyina LK. Growth and age of , white bream, the length-weight relationship of skipjack tuna (Katsuwonus roach, and white-eye bream of Gorkovsky Reservoir. Trudy pelamis) caught in the southwest South Atlantic. Fisheries Instituta Biologii Vodokhranilishch 3: 16-251, 1960. Research 55: 307-12, 2002. 31. Gursoy Ç. Sexual Seniority and Egg Fertility of White bream 22. Mommsen TP. Growth and metabolism. In: Evans DH. ed. Th e (Blicca bjoerkna L. 1758) and Vimba (Vimba vimba L. 1758) in Physiology of Fishes. CRC Press. New York; 1998: pp. 65-97. Sapanca Lake. MSc thesis. İstanbul University Natural Sciences Institute. İstanbul; 2001. 23. Morey G, Moranta J, Massutí E et al. Weight-length relationships of littoral to lower slope fi shes from the western 32. Koli L. Suomen kalat. [Fishes of Finland] Werner Söderström Mediterranean. Fisheries Research 62: 89-96, 2003. Osakeyhtiö. Helsinki; 1990. 24. Tesch FW. Age and growth. In: Methods for Assessment of 33. Berg LS. Freshwater Fishes of the U.S.S.R. and Adjacent Fish Production in Fresh Waters. WE Ricker (Ed). Blackwell Ocuntries. Academy of Sciences of the USSR 2; 1949. Scientifi c Publications. Oxford; 1971: pp. 98-130. 34. Keith P, Allardi J (coords.). Atlas des poissons d’eau douce de France. Muséum national d’Histoire naturelle, Paris. 25. Treer T, Habekovic D, Anicic I. Th e growth of fi ve populations Patrimoines naturels, 47: 1-387, 2001. of chub (Leuciscus cephalus) in the Danube River Basin of Croatia. Proc. Internat Symp Aquarom Galati. Romania; 1988: 35. Pinder AC. Keys to larval and juvenile stages of coarse fi shes pp. 18-22. from fresh waters in the British Isles. Freshwater Biological Association. Th e Ferry House, Far Sawrey, Ambleside, 26. Treer T, Habekovic D, Safner R. Length-mass relationship in Cumbria. UK; 2001. chub (Leuciscus cephalus) from fi ve Croatian Rivers. Agric Conspectus Sci 64: 137-42, 1999. 36. Spratte S, Hartmann U. Fischartenkataster: Süßwasserfi sche und Neunaugen in Schleswig-Holstein. Ministerium für 27. Kirilyuk OP. Age Structure and Growth of White Bream (Blicca ländliche Räume, Landwirtschaft , Ernährung und Tourismus. bjoerkna) in Kremenchug Reservoir. Gidrobiologicheskiy Kiel Germany; 1997. Zhurnal 27: 92-97, 1991. 37. Nikolsky GV. Th e ecology of fi shes (translated by L. Birkett). 28. Hacker R. Fishes and Fishery in Neusiedlersee. In: H. Löff er Academic Press. London; 1963. (Ed.) Neusiedlersee: Th e limnology of a shallow lake in Central 38. Okgerman H, Elp M, Yardımcı CH. Growth, the length-weight Europe. Dr. W. Junk by Publisher. London; 1979: pp. 428-438. relationship, and reproduction in vimba (Vimba vimba L. 29. Slastenenko E. Fish of Black Sea Basin. Meat and Fish 1758) sampled from an oligo-mesotrophic lake in northwest Institution Publications. Istanbul; 1956. Anatolia (Turkey). Turk J Zool 35: 87-96, 2011.

134