In the present study, accumulation of manganese, cadmium, zinc, iron and copper in the commercially fish species (silver pomfret and tiger tooth croaker) caught from Bandarabbas coasts at 2010 was measured and the risk of daily intake of them in Hormozagan urban population was estimated. The average concentrations (μ/g dry weight) of manganese, cadmium, zinc, iron, and copper in the muscle tissue of silver pomfret were 1.248, 0.217, 14.444, 2.397 and 3.300, respectively, while the concentration of them in tiger tooth croaker were 1.009, 0.403, 12.564, 4.467 and 2.366, respectively. According to fish consumption rate, urban populations of the province were divided into four groups, low, medium, high and very high. The target hazard quotient (THQ) in each group calculated separately. The THQ of all groups were much lower than 1 in the two fish. The results showed that urban populations of the province have not any risk due to accumulation of the studied heavy metals.

SPIRLIN (Alburnoides eichwaldi) is a stream species that has a good abundance in southern basin of Caspian sea, but it is supposed to be extincted in many inland waters of Europe. There hasn’t been any study about genetic diversity of this species yet. In this study, the genetic diversity of Alburnoides eichwaldi from Kaboodwal and Sefidrood streams was investigated by 6 microsatellite loci. According to the results, the Fst values was 0.020. Most of the loci showed deviation from Hardy-Weinberg equilibrium. The number of alleles, observed and expected heterozygosity were, 8-21, 0.541-1 (the average: 0.853 ± 0.06) and 0.834-0.927 (the average: 0.887), respectively. This indicates the allelic diversity and genetic variation of investigated populations is at favorable level. Also, analysis of molecular variance showed there is low genetic variation among populations and most of the observed variation is within the populations. Results based on genetic distance indicated that SPIRLIN populations are separated from each other in the investigated streams.

A total of 48 female SPIRLINs Alburnoides sp. from the Kesselian stream (South Caspian Sea basin, northern Iran) were examined during a period from July 2008 to June 2009 to obtain data on fecundity, and to determine the spawning season of this carp. The mean absolute fecundity of females SPIRLIN was 1722.92 (±653.88) eggs. The fecundity has positive correlation with the size of the female. The mean of the monthly GSI index and ova diameters shows that SPIRLIN spawn once in a year during the months of June-July. GSI of 6.88 was considered as the indicator of sexual maturity for the females. The highest peak of relative condition factor (Kn) was 0.126 during the month of June. The stages of gonads maturation of Caspian SPIRLIN have been classified as: I, immature; II, early developing; III, late developing; IV, mature; V, ripe (spawning).

In this study, the distribution, abundance and some growth parameters of SPIRLIN, Alburnoides eichwaldii in the Tilabad stream in the Golestan province was studied over 2009-2010. A total of 535 samples of SPIRLINs were collected by catching with Electroshocker. A total number of 205 samples was analyzed and the rest of the specimens were released. SPIRLIN was found only in stations 1 and 2 (the Headstream and next station) while station 2 had the highest number of summer Sprilin (0.889 # m-2). Catched fish were in three age-groups: 0, 1+, and 2+ years old with the longitudinal range of 25.34-110.16 mm. The exponential relationship between length and weight in both sexes indicated negative allometric growth. Growth equation was Lt=12.45 (1-e-0.248 (t+0.39)) and Lt=11.66 (1- e-0.281 (t+0.39)) for females and males of SPIRLIN, respectively. Apparently, SPIRLINin in the Tialabad stream has no biotic suitability and faces severe environmental stress.

SPIRLIN (Alburnoides bipunctatus) is a stream species that has a good abundance in southern basin of Caspian sea, but it is supposed to be extincted in many inland waters of Europe. There hasn’t been any study about genetic diversity of this species yet. In this study, 84 fish were collected from Tilabad, Shirabad and Kaboodwal streams in Golestan Province (28 samples from Tilabad, 28 samples from Shirabad and 28 samples from Kaboodwal) to investigate their population structure. DNA was extracted by phenol-chloroform method and screened for 6 microsatellite loci. The average of expected heterozygosity and observed heterozygosity were 0.893 and 0.817, respectively. The analysis of molecular variance showed high genetic diversity (98%) within investigated populations. The Fst value was 0.024 which indicates a low genetic differentiation between the Tilabad, Shirabad and Kaboodwal populations. In examining deviations from Hardy- Weinberg equilibrium, two loci in Tilabad population and two loci in Kaboodwal population were balanced and other loci had a significant diviation from Hardy-Weinberg equilibrium (P≤0.05). According to UPGMA cluster analysis based on genetic distance, populations of Tilabad and Shirabad rivers haven’t been separated, but possibly Kaboodwal river population has been separated from two other rivers’ populations.

Age, growth, and reproductive traits of the South Caspian SPIRLIN in the southern part of the Caspian Sea basin, Tajan, River, were investigated. A comprehensive study was conducted on 663 specimens including 226 females, 297 males, and 140 unsexed individuals with a total length ranging from 25.88 to 121.66 mm. The specimens were collected using an electrofisher at monthly intervals. The female-to-male sex ratio was calculated as 1: 1.29. The growth rings on the scale were employed for age determination in this study. Both sexes exhibited only four age groups (0+ to 3+), with the 2+ age group dominating the population. Females consistently displayed larger sizes compared to males. The von Bertalanffy growth function yielded L t =123.90 (1- e -0.25(t+0.87) )  and L t =128.10 1- e -0.29 t+0.69  for males and females, respectively. Furthermore, the Fulton condition factor value was significantly higher in females than males. Notably, the maximum gonadosomatic index for both males and females coincided with the spawning seasons (May to August). Absolute fecundity varied from 290 to 1710 oocytes, with a mean of 793 oocytes. This study presents comprehensive data on the biological characteristics of the South Caspian SPIRLIN, providing valuable insights for fish stock assessment studies.

Introduction The genus Alburnoides belongs to the Leuciscine cyprinids and is distributed in Europe and eastern parts of Asia.Only two subspecies have been consistently reported forAlburnoides bipunctatus (Heckel, 1858) from Turkey (Kuru, 2004), A. bipunctatus eichwaldiiand A. bipunctatus fasciatus.Just a few years ago, some taxonomic work focusing on the genus Alburnoidesreported 4 new species from Turkey (Turanet al., 2013; 2014).

During 13 months of sampling (September 2009 to Sep 2010), 809 SPIRLINs (Alburnoides bipunctatus) were caught from Mazandaran Talar river from which 412 SPIRLINs belonged to Keselian cluster and 397 SPIRLINs belonged to Tejoon cluster. Fishing was performed by a 250-300 volts electro-shocking machine. The assessments showed 30 morphometric and 10 meristic specifications. The result of t-test indicated a meaningful difference in 13 morphometric & 7 meristic specifications between SPIRLIN fish of The Two clusters (P≤0.05). Four age classes were observed in SPIRLIN population in which the age group of 2⁺ was the most abundant (49%). Also, in general, the total population consisted of female fish (50%), male fish (39%) and immature fish (11%). The maximum length in this research was 96.14 mm and the maximum weight was 9.27 grms. The relationship between length-weight showed a high correlation between Keselian cluster (r2=0.98) and Tejoon (r2=0.97). The conditional factor indicated the obesity of most Keselian species. The growth pattern has shown a negative alometric pattern in SPIRLIN species of the two clusters and Instant growth rate of immature species has been more compared to other age groups. It can be concluded that SPIRLINs of the two clusters have some differences considering some morphplogical specifications and for a more complete population segregation of this species, modern genetic methods must be used such as PCR, Electrophoresis and micro satellite.

Age structure, growth and mortality index of 661 specimens of SPIRLIN, Alburnoides eichwaldii, from Shirood River in Mazandaran Province were studied during April 2011 to March 2012. The average total length, weight and age of the specimens were 68.33 ± 16.92 mm, 4.9 ± 3.2 g and 1.32 ± 0.86 years, respectively. The fish were in the age range of 0+to 3+, of which the 0+year specimens dominanted the age groups in the river. The largest specimen was 111.4 mm in length and a weight of 15.5 g. Comparing total length and weight of fish showed significant differences various ages (P<0.05). Based on Pauly formula, population growth pattern was negatively allometric (b=2.94). Based on von Bertalanffy growth equation using the FiSAT program, L, K and t0 were 12.08, 0.55, and -0.47, respectively. The growth performance index was up to 3.65. Mortality indices for the fish were calculated as 2.41, 1.19 and 1.22, respectively for the total (Z), natural (M) and fishing (F). Considering the ecological, biological and ornamental value of SPIRLIN as well as its vulnerabilty to serious environmental degradation, such studies may be useful in the protection of the species.

Understanding of habitat requirements of a fish species is a research priority for its management and conservation. The biological characteristics and habitat requirements of Alburnoides tabarestanensis have not been studied yet. Therefore, this work aimed to study large-scaled i.e. water velocity, depth, river width, and bed type habitat suitability indices of endemic Tabarestan SPIRLIN in the Kela River (a tributary of the Babel River, Caspian Sea Basin). For this purpose, a total of six stations along this River were sampled using an electrofishing device in a 30 m length of river with three replications. Based on the results, the preferred range of environmental variables of Tabarestan SPIRLIN were a water depth of 17-20 cm, river width of 8.8-4.8 m, water current of 5-6 m / s, bed index of 3.5-8.8. The bedrock diameter was 7.5-5 cm. The results also showed that the selected habitat characteristics of Tabarestan SPIRLIN are those with higher depth, boulder substrate type, lower width and lower water current that can be adversely affected by human activities such as sand and water harvestings.