Otolith Mass Research Articles

Relationships between body length, body mass and otolith dimensions in three Sprat species (Teleostei: Ehiravidae) from the Caspian Sea

AbstractReliable and detailed knowledge regarding the relationship between otolith size and the size of fish is important for fisheries management and for ecological studies on predicting fish size and on predator–prey interactions. Therefore, these relationships are estimated for three sprat (genus Clupeonella) species, including C. caspia, C. engrauliformis and C. grimmi from the Caspian Sea. The relative size and mass of the otoliths corrected for body size and mass were also estimated for the three sprat species. After biometry of collected specimens, the Sagittal otoliths were extracted from the cranium of collected specimens and photographed. Photos were used to estimate length and width of otoliths. The results revealed significant relationships between otolith length and width vs. fish length and otolith mass vs. body mass in all three species (r2 > 0.5). The higher coefficient of determination (r2) for relationships between total length (fish) – Otolith length and width was concluded in comparison with relationships between fish mass and otolith mass in the studied sprat species. Otoliths of C. grimmi showed the highest relative length and were significantly (P < 0.05) heavier than sagittal otoliths of two other sprat species. There is no previous report on size–mass relationships between fish and otolith measurements among the three studied sprat species. These estimated equations can be used in back-calculation studies, especially for these three sprats as the dominant prey for piscivorous predators such as Caspian seals and sturgeons, in their habitats.

Age, growth, and mortality of Blackfin Tuna in the Gulf of Mexico

AbstractObjectiveAn otolith‐based aging approach was used to evaluate age and growth relationships, sexual dimorphism in growth, and derive mortality estimates for Blackfin Tuna Thunnus atlanticus in the Gulf of Mexico (GOM).MethodsBlackfin Tuna (n = 395) were sampled from recreational fisheries and aged from 0 to 13 years, representing an increase over previous estimates of longevity for the species.ResultRapid growth was exhibited during the first two years of life, and the Richards growth function provided a better fit (L∞ = 907 mm, k = 0.112 /year, a = 1.05, b = 0.25) to the data compared with the von Bertalanffy growth model (L∞ = 824 mm, k = 0.365/year, t0 = −0.96). Sexual dimorphism in growth was observed, with males (907 mm) reaching a larger L∞ than females (857 mm), and otolith mass was a strong predictor of age in both sexes. Estimated instantaneous total (Z = 0.532/year) and natural (M = 0.467 year) mortality rates for Blackfin Tuna in the GOM were low relative to previous estimates in the southwestern Atlantic, where fishing mortality (F) is likely much higher.ConclusionResults represent critical baseline estimates of size‐at‐age, longevity, and natural mortality for Blackfin Tuna at relatively low levels of exploitation that can be used to inform future assessments.

Investigation of otolith mass asymmetry of Squalius sp. populations sampled from different freshwater sources in Samsun Province (Türkiye)

This research aimed to determine and compare the otolith mass asymmetry (OMA) of Squalius sp. species sampled from ten different freshwater sources in Samsun province. In this context, fish samples obtained from Abdal Stream, Akçay Stream, Engiz Stream, Istavloz Stream, Kaynatma Stream, Mert River, Taşkelik Stream, Terme Stream, Tersakan Stream, Yeşilpınar Stream. The difference between the right and left otoliths were found to be statistically significant in the Istavloz Stream and Tersakan Stream for the asteriscus and in the Abdal Stream for the lapillus (p0.05). This is the first study in which OMA and absolute otolith mass asymmetry of Squalius sp. living in the freshwaters of Samsun province were investigated, and their relationships with fish length were evaluated.

Otolith Mass Asymmetry of Pampus candidus (Osteichthyes, Stromatidae) from Iraqi Marine Waters

The otolith mass asymmetry of the fish species Pampus candidus was assessed. The findings indicated a significant level of asymmetry comparison with similar studies on other fish species. The level of asymmetry was shown to increase with the size of the fish, where the utmost estimate of the otolith weight irregularity was obtained. The detected otolith asymmetry may be linked to pollutants in the sampling area.

Türkiye’den üç sardalya, Sardina pilchardus (Walbaum, 1792) stoğunun otolit kütle asimetrisinin incelenmesi

It was aimed to investigate sagittal otolith mass asymmetry Sardina pilchardus sampled from Aegean, Marmara and Mediterranean seas of Türkiye in present study. In this study, differences between right and left otoliths were statistically significant for Marmara and Mediterranean seas (P<0.05) not significant for Aegean Sea, (P˃0.05). The mean values of otolith mass asymmetry (X) were found between 0.0393 and 0.0144 according to Aegean Sea, Marmara Sea and Mediterranean Sea, respectively. In addition, absolute mass asymmetry │X│ were calculated as 0.03226±0.00514, 0.02057±0.00439 and, 0.05141±0.00755 for S. pilchardus samples according to Aegean Sea, Marmara Sea and Mediterranean Sea, respectively. The present study showed that the otolith mass asymmetry in S.pilchardus does not depend on fish length and otolith growth. Also, when there were no significant differences between localities for otolith mass asymmetry (P˃0.05), there were significant differences for absolute otolith mass (P˂0.05). The value of the otolith mass asymmetry can reveal information about pollutants such heavy metals, pesticides, stressors, and changes in the physico-chemical characteristics of water in relation to the environment of fishes. This is the first study about otolith mass in three stocks of S. pilchardus (Walbaum, 1792) from Türkiye.

Biometric relation between body size and otolith size of Cyprinionkais and C. macrostomum collected from Tigris River, Şırnak Province,Türkiye

One hundred and twenty asterisci were obtained from 30 specimens each of Cyprinion kais and Cyprinion macrostomum. Significant relationships between otolith mass and the three fish lengths (TL, SL, and FL) were attained for C. kais. Similar associations were obtained for OL and the three fish lengths of C. macrostomum. For C. kais, the highest in the relation between otolith mass, hereafter referred to as OM, and fish fork length, henceforth known as FL (0.5894). The lowest coefficient of determination was observed between otolith width, hereafter called OW, and standard fish length, hereafter referred to as SL (0.2861). For C. macrostomum, the highest coefficient of determination was attained for the relation between OL and FL (0.7280) and the lowest for the relationship between OM and TL (0.1717).The analysis shows that evaluations of the body size of the two fish species investigated through biometric studies of otoliths are trustworthy.

Distinct inter and intrapopulation variation in the otolith shape and size of Mullus barbatus (Actinopterygii: Mullidae) from the Bizerte and Ghar El Melh lagoons in Tunisian waters

ABSTRACT This study aimed to assess the geographic variation in otoliths’ shape and size and the effect of potential fluctuating asymmetry (FA) in otolith size on the stock structure of Mullus barbatus collected from the Bizerte and Ghar El Melh lagoons located in northeastern Tunisia and to evaluate the relationship between the otolith mass asymmetry (OMA) and total length (TL). Analysis of the otolith shape showed a statistically significant intersexual shape difference, i.e. asymmetry, in the left and right and left-left and right-right otoliths between populations of the two lagoons. In addition, significant intersexual differences were detected in Lo, Wo, and Mo, as well as in FA, between the left and right otoliths among the two populations. Moreover, no statistically significant relationship (P > 0.05) was found between OMA and TL between and within the two populations. At the intrapopulation level, a significant intrasexual asymmetry was observed in the left and right, as well as on left-left and right-right sides, otoliths’ shape and size only within the Ghar El Melh lagoon. Discriminant function analysis of the otoliths’ contour shape confirmed the presence of two separate stocks representing the Bizerte and Ghar El Melh lagoons, which should be managed separately. This significant inter and intrapopulation asymmetry detected in otolith shape and size due to FA can be attributed to the instability of larval development caused either by environmental stress associated with variation in water temperature, salinity, feeding conditions and pollutants or due to poor living conditions of larvae resulting from unfavourable environments.

The possibility of using otolith parameters to determine the age of the dub Limanda limanda (Pleuronectidae) on the example of the Chupa Bay of the Kandalaksha Bay in the White Sea

The paper investigates the possibility of determining the age of dub Limanda limanda Linnaeus, 1758, by the length, width, thickness and mass of the otolith. The purpose of the study is to evaluate the possibility of using this method. A total of 247 otoliths (172 females and 75 males) were processed. The age of the dub in the Chupa Bay ranged from 2 to 12 years, while the sample was based on individuals 3–6 years old (81.8%). The average values of the otolith parameters for each age class are given. The dependences between age and otolith parameters are expressed by a logarithmic function. Regression equations describing the relationship between the age of an individual and the parameters of the otolith of the dub were calculated, and a correlation between these indicators was noted. The calculated correlation coefficients of the dependence of the age of the fish on the otolithometry parameters showed that the highest values of the coefficients were revealed by the dependencies "age of the fish – mass of the otolith" and "age of the fish – thickness of the otolith". It was found that the same-aged females have large values of the length and mass of the otolith compared to males. It is recommended to use the otolith mass as an express method for determining the age of the dub. There are no similar works on the dub in the scientific literature.

Investigation of otolith asymmetry in Mulloidichthys flavolineatus and Parupeneus forsskali (Perciformes: Mullidae) from Egypt’s Hurghada fishing harbour on the Red Sea

The current study aims to calculate and assess the asymmetry of the two goatfish species, Yellowstripe goatfish Mulloidichthys flavolineatus (Lacepède 1801) and Red Sea goatfish, Parupeneus forsskali (Fourmanoir & Guézé 1976) collected from Hurghada fishing harbour, Egypt. The asymmetry valuation for M. flavolineatus and P. forsskali is imperative to demonstrate the impact of asymmetry on the larvae settlement in this vital fishing ground. Asymmetry was calculated for the saccular otolith (Sagittae) biometry, namely length, width, and mass. The results showed that the otolith height had a lower asymmetry value than the otolith length for the two goatfish species inspected. No relationship between the asymmetry value of otolith length and width and total fish length was observed. Both goatfish species’ calculated otolith mass asymmetry was higher than that of many teleost fish species.

Bilateral Asymmetry in Asterisci Otoliths of Cyprinion kais and C. macrostomum (Cypriniformes, Cyprinidae) collected from Tigris River, Şirnak Region, Türkiye

Otolith traits such as size and mass were investigated in 60 fish specimens of C. kais and C. macrostomum collected from the Tigris River, Şırnak region, Türkiye collected from September 2015 to December 2015. The purpose of this work was to determine the asymmetry level in the otolith length (OL), otolith width (OW), and otolith mass (OM). OL's rate of asymmetry was greater than OW’s and OM's. The asymmetry in the three otolith traits rose with the fish length. The plausible reason for asymmetry in the otolith features explored has been considered relative to the inconsistency of growth triggered by ecological influence associated with the inconsistency in water temperature, salinity, depth, and contaminants occurring in the Tigris River System.

Otolith phenotypic variation as an indicator of stock structure of Scomberomorus brasiliensis from the southwestern Atlantic Ocean

Phenotypic variation of Scomberomorus brasiliensis otoliths was evaluated by testing the null hypothesis of a single stock across the southwestern Atlantic Ocean. Otolith sampling of S. brasiliensis (n = 396) took place between July and October 2019 at nine locations along the Brazilian coast. The shape of each otolith contour was assessed with elliptic Fourier descriptors (EFDs) and their variation evaluated through multivariate analyses. Fish size-otolith size relationships were used to explore interregional differences in S. brasiliensis growth. Cluster analysis based on EFDs separated the sampling locations into tropical (2°S to 20°S) and subtropical (23°S to 27°S) Atlantic regions. The variation of EFDs between these regions was over twice as large as the within region variation. Linear discriminant analysis (LDA) discriminated between regions with 72.85% overall accuracy. Subtropical fish were characterized by the lowest otolith mass at fish size, suggesting great conditions for the growth of S. brasiliensis in subtropical waters. Local phenotypic structuring among S. brasiliensis population units was less evident (LDA, 29.6% overall accuracy), most likely due to high demographic connectivity on short spatial scales, or even, small environmental heterogeneity to promote discrete phenotypic in S. brasiliensis otoliths. Yet, EFDs from distant population units (2°S and 23–27°S) were statistically similar and a likelihood of extensive longshore migration could not be excluded with the herein used approach. These results suggest, however, regional population units appear not regularly mix and fishery managers need to consider such Atlantic regions as functionally distinct management units in a metapopulation perspective.

Otolith mass asymmetry in three sparid fish species collected from the Iraqi waters

Saccular otolith mass asymmetry is examined in three sparid fish species, Acanthopagrus bifasciatus, A. arabicus, and Sparidentex hasta collected from Khor Abdullah at the North Persian Gulf. This characteristic was computed as the disparity between the weight of the right and left otoliths divided by mean otolith weight in the three sparid species investigated. According to the previous cases obtained on another symmetrical fish species, the absolute value of x in these species does not determine by fish length and otolith growth ratio, while the absolute rate of otolith weight disparity is boosted with the fish length. The estimate of x was between -0.2 and +0.2. Otolith mass asymmetry can show some growth disorder of fish owing to environmental influence.

Investigating otolith mass asymmetry in six benthic and pelagic fish species (Actinopterygii) from the Gulf of Tunis

Otolith mass asymmetry can significantly affect the vestibular system functionalities; usually, the X values of mass asymmetry vary between −0.2 and + 0.2 (−0.2 < X < + 0.2). These values can change during a fish life and therefore they are not related to the fish total length. We collected a total of 404 fish specimens from the Gulf of Tunis, including three pelagic species: Sardina pilchardus (Walbaum, 1792) (74 otolith pairs), Trachurus mediterraneus (Steindachner, 1868) (66 otolith pairs), and Chelon auratus (Risso, 1810) (60 otolith pairs) and three benthic species: Gobius niger Linnaeus, 1758 (77 otolith pairs), Mullus barbatus Linnaeus, 1758 (60 otolith pairs), and Trachinus draco Linnaeus, 1758 (67 otolith pairs). The relation between the total length and the otolith mass asymmetry was first calculated and compared, and then was evaluated. The comparison of the otolith mass asymmetry between benthic and pelagic species showed a significant difference (P < 0.05), where the absolute mean value of X does not exceed the critical value (0.2) for all the studied species. No relation has been found between the magnitude of the otolith mass asymmetry and the length in both benthic and pelagic specimens. Environmental factors have an indirect effect on somatic growth and otolith accretion. The significant difference found in this study can be due to the difference between the benthic and pelagic environments.

Age and growth of early-life-stage Atlantic tarpon (Megalops atlanticus) from the northcentral Gulf of Mexico.

Age and growth of early-life-stage Atlantic tarpon Megalops atlanticus collected from Mississippi coastal waters in the northcentral Gulf of Mexico (GOM) are described using otolith microstructure analysis. Tarpon leptocephali (n= 95, 16.0-27.8 mm standard length, LS ) collected from June throughOctober 2013-2018, ranged in age from 22 to 43 days (mean=30.9± 0.5 days). Leptocephalus somatic growth rates ranged 0.46-1.24 mm day-1 (mean=0.76 ± 0.02 mm day-1 ), and leptocephalus otolith growth rates ranged 1.78-3.97 μm day-1 (mean=2.58 ± 0.04 μm day-1 ). Growth rates were inversely correlated to leptocephalus age, indicating the shrinkage phase associated with leptocephalus metamorphosis. Juvenile tarpon (n= 358, 50-359 mm fork length, LF ) were collected from August through December 2007-2018. Juveniles exhibited a positive allometric relationship (adjusted R2 = 0.99, P< 0.001) between length and mass. The age of 100 juveniles (71-277 mm LF ) ranged from 76 to 174 days. Juvenile growth rate was estimated as 1.56 ± 0.11 mm day-1 . Significant (P< 0.001) linear relationships were found between juvenile age and otolith metrics, including otolith mass (R2 = 0.81) and radius (R2 = 0.68). Evaluation of the backcalculated hatch dates suggests that specimens in the collection hatched from late May through mid-September with slight peaks during July and August. A Rao's Spacing Test of Uniformity indicates the presence of significant lunar periodicity in leptocephalus hatch dates (n= 95, U= 250.1, P< 0.05), with 50% of the leptocephali hatched within 5 days (before or after) of the full moon. This study fills critical gaps in the scientific knowledge of tarpon and provides estimates of early-life-history metrics for an iconic game fish at the northernmost extent of its GOM range.

Comparative analysis on otolith shape of &amp;lt;italic&amp;gt;Champsocephalus gunnari&amp;lt;/italic&amp;gt; and &amp;lt;italic&amp;gt;Cryodraco antarcticus&amp;lt;/italic&amp;gt; based on four morphological techniques

To study the effectiveness of otolith morphological techniques on the population classification of Antarctic ice fish, based on the collected samples of <italic>Champsocephalus gunnari</italic> and <italic>Cryodraco antarcticus</italic>, 5 kinds of basic otolith morphological parameters were measured and converted into 7 morphological indicators, the differences in otolith morphology of two species were compared and analyzed, principal component analysis (PCA), stepwise discriminant analysis (SDA) and random forest (RF) were then used to discriminate the 77 elliptical Fourier harmonics of otolith morphological parameters. The results showed that the otolith parameters and body length of two species were significantly correlated (<italic>P</italic>>0.05). The body length of <italic>C</italic>. <italic>gunnari</italic> showed a power function relationship with some morphological parameters. While otolith length, otolith height, otolith area, otolith perimeter, otolith mass of <italic>C</italic>. <italic>antarcticus</italic> were all in logarithmic relationship with the body length. It could be seen that the otolith ring rate of <italic>C</italic>. <italic>gunnari</italic> was lower than that of <italic>C</italic>. <italic>antarcticus</italic>, compared to the otolith of <italic>C</italic>. <italic>antarcticus</italic>, the otolith of <italic>C</italic>. <italic>gunnari</italic> was rounder and more regular. The conventional morphological analysis could not discriminate the otoliths of two species. The PCA could discriminate the otoliths of two species, and the discriminant success rates of SDA and RF were 98.78% and 91.67%, respectively. SDA has its advantage in small sample size, but RF is suitable for large sample size.

Otolith fluctuating asymmetry inBoops boops(Actinopterygii, Sparidae) from two marine stations (Bizerte and Kelibia) in Tunisian waters

AbstractFor the first time, saccular otolith shape and size were analysed in 254 samples of the bogueBoops boopscollected from the marine stations of Bizerte and Kelibia situated in north-east Tunisia. The objectives were (1) to examine the inter- and intra-population variation in the otolith shape and size, including length (Lo), width (Wo) and area (Ao) measurements, and (2) to assess the relationship between otolith mass asymmetry (OMA) and total fish length (TL). In addition, the impact of pollution present in these two stations on the shape and size of the otolith in relation to the TL was discussed. Analyses of the otolith shape and biometric data showed a statistically significant asymmetry in the otolith shape (P&lt; 0.0001) between the right and left sides within the population of Bizerte, as well as between the otoliths from the same right-right and left-left sides between the populations of Bizerte and Kelibia. Similarly, a significant Wo asymmetry (P&lt; 0.05) was recorded within the population of Kelibia. Conversely, a significant symmetry was detected in Lo and Ao (P&gt; 0.05) between the right and left sides within the populations of Bizerte and Kelibia. Moreover, the level of asymmetry of Ao was higher than that of Lo and Wo in both populations. Nevertheless, Student'st-test showed no statistically significant differences (P&gt; 0.05) for Lo, Wo and Ao in relation to the means of TL between the three groups of the populations of Bizerte and Kelibia, although significant differences (P&lt; 0.05) were found by using box plots. Furthermore, no statistically significant relationship (P&gt; 0.05) was detected between OMA and TL within and between the populations of Bizerte and Kelibia. The possible cause of fluctuating asymmetry (FA) in the otolith shape and size both within and/or between populations of the two stations has been discussed in relation to the instability of development induced by environmental stress associated with the variation in water temperature, salinity, depth, feeding conditions and pollutants present in these stations.

Age determination in the icefish Pseudochaenichthys georgianus (Channichthyidae) based on multiple methods using otoliths

Aging Antarctic icefish is difficult because of their lack of scales and poorly calcified bones. Icefish ages must therefore be estimated from otoliths. We describe a method of reading daily micro-increments in connection with shape, size and mass analyses of the otoliths of the South Georgia icefish Pseudochaenichthys georgianus. Changes in otolith morphology and mass correlate with fish size and age group. The otolith micro-increment analysis is capable of establishing the age of an icefish by relating the daily micro-increment count to the life history of the fish. Micro-increment measurements and analyses are relatively simple to do by light and scanning electron microscopy and by using micro-densitometer and digitizing equipment. Drastic changes in the life history of an individual are reflected by measurable changes in its otolith micro-increment data as seen in our analyses of age groups 0-VI. The initial drastic change in daily micro-increment shapes and periodicities occur in connection with the hatching period of the icefish. The next drastic change in otolith shape and daily micro-increments occurs when ~7 cm long fish shift from pelagic to benthic habitats. As the fish age beyond group III, individual otolith variability lessens until they begin spawning. Our results indicate a single population of P. georgianus between the Antarctic Peninsula and South Georgia.

Aşağı Melet Irmağı (Ordu, Türkiye)’nda Yaşayan Barbus tauricus Kessler, 1877 Otolit Kütle Asimetrisinin Belirlenmesi

Kemikli balıklar, otolit kütle asimetrisinin fizyolojik rolünü değerlendirmede en uygun organizmalardır. Asimetri, balığın vestibular ve işitsel fonksiyonları üzerinde şiddetli etkilere sebep olan bir faktördür ancak bu konuyla ilgili sınırlı sayıda çalışma bulunmaktadır. Türkiye sularındaki tatlı su türlerinin asimetrileri hakkında birkaç çalışma vardır. Bu çalışmanın amacı, Barbus tauricus Kessler, 1877’un otolit kütle asimetrisini belirlemektir. Balık örnekleri Temmuz 2010-Ekim 2011 tarihleri arasında serpme ağlar kullanılarak aşağı Melet Irmağı’ndan yakalanmıştır. B. tauricus bireylerinin sağ ve sol otolitleri arasındaki fark, paired-t testine göre istatistiksel olarak önemli bulunmuştur (P&amp;lt;0,05). Ortalama x ve |x| değerleri 0,0685±0,0194 ve 0,2377±0,0135 olarak hesaplanmıştır. Balık boyu-x, balık boyu-|x| ve balık boyu-(MR-ML) arasındaki ilişkiler sırasıyla y=0,0011x+0,0434; y=0,0066x+0,1457 ve y=0,0000008x+0,00003 olarak tespit edilmiştir. Otolit kütle asimetrisi değeri, balıkların yaşadıkları ortamla ilişkili olarak ağır metaller, pestisit, tarım ilaçları gibi kirlilik etkenleri, stres oluşturan faktörler, suyun fiziko-kimyasal özelliklerinde meydana gelebilecek değişimler hakkında bilgi verebilir. Diğer tatlı su türlerinde yapılan çalışmalarla karşılaştırıldığında, ortalama otolit kütle asimetrisi değerinin daha yüksek olarak belirlenmesi, ırmağın B. tauricus bireyleri üzerindeki çevresel etkisini de ortaya çıkarmıştır.

Aşağı Melet Irmağı (Ordu, Türkiye)’nda Yaşayan Capoeta banarescui’nun Otolit Kütle Asimetrisinin Belirlenmesi

Asimetri, balığın vestibular ve işitsel fonksiyonları üzerinde önemli etkilere sebep olmaktadır fakat bu konuyla ilgili olarak sınırlı sayıda çalışma bulunmaktadır. Bu çalışmanın amacı, Ordu ili içme su kaynağı olarak da kullanılan Melet Irmağı’nda yayılış gösteren C. banarescui türünde, daha önceden belirlenmemiş olan, otolit kütle asimetrisi (x) ve mutlak otolit kütle asimetrisinin (|x|) belirlenmesidir. Balıkların total boyları ölçülmüş, asteriskus otolit çiftleri çıkarılarak 0,0001 hassasiyetle tartılmıştır. Otolit kütle simetrisi (x), mutlak otolit kütle asimetrisi (|x|) ve otolit kütle farkı (MR-ML) değerleri hesaplanarak, balık boyu ile x, |x| ve (MR-ML) arasındaki ilişkiler belirlenmiştir. C. banarescui bireylerinin sağ ve sol otolit ağırlıkları arasındaki fark, paired-t testine göre istatistiksel olarak önemsiz bulunmuştur (P&amp;gt;0,05). Ortalama x ve |x| değerleri -0,00803 ve 0,0855 olarak hesaplanmıştır. Total boy-x, total boy-|x| ve total boy-(MR-ML) arasındaki ilişkiler sırasıyla y=0,0011x+0,0434; y=0,0066x+0,1457 ve y=0,0000008x+0,00003 olarak tespit edilmiştir.

A preliminary investigation of the relationship between otolith weight and age for Chondrostoma regium (Heckel, 1843) (Teleostei: Cyprinidae)

To our knowledge, no study is available on the relationships between otolith mass and age as well as body weight and length of Chondrostoma regium (Heckel, 1843) in the Zayandeh River, hence the present study attempted to examine this rather simple, efficient and cost-effective approach to contribute in providing more objective information required in age-related studies of this species. During March-April 2017 random samples of C. regium were collected by a river seine in the Zayandeh River. Sampled fish ages were between 2 to 5 years and ranges of total length, body weight and otolith mass averages of samples were 82.2-161.6mm, 5.35-42.35g and 4.1-7.3mg, respectively. As the fish grow, total length, body weight and otolith mass averages showed a clear increasing trend. The results revealed significant positive relationships between variability of body length and otolith weight ( P <0.05) as well as variability of body weight and otolith mass ( P <0.05) of C. regium . Furthermore, an obvious significant increasing trend of otolith mass with age increment ( P <0.05) is found. The average weights of otoliths in the present study increased with age, length and weight which evidently confirms that the otolith mass increase in C. regium is in compliance with somatic growth through the ontogenetic processes.