Iran. J. Ichthyol. (December 2019), 6(4): 254-263 Received: December 18, 2018 © 2019 Iranian Society of Ichthyology Accepted: June 1, 2019 P-ISSN: 2383-1561; E-ISSN: 2383-0964 doi: 10.22034/iji.v6i4.361 http://www.ijichthyol.org Research Article

Life history traits of the Caspian stellate tadpole-goby Benthophilus leobergius Berg, 1949 (Teleostei: ) from the southeastern , Iran

Rahman PATIMAR*, Abdol-Saleh QARANJIKI, Arsalan BAHALKEH

Department of Fisheries, Faculty of Natural Resources, Gonbad Kavous University, Golestan, Iran. *Email: [email protected] Abstract: The Caspian stellate tadpole-goby, Benthophilus leobergius is endemic to for the Caspian Sea. In Iranian waters of the Caspian Sea, however, little is known about its life history. To address this, life history characteristics were examined in 256 specimens collected from the southeastern Caspian Sea, northern part of the Miankaleh Wildlife Refuge. The maximum observed age was 2+ years for both sexes. The sex ratio of males to females was 1:1.70. Estimated length-weight relationship was TL=0.0088TW3.289 for males, TL= 0.0099TW3.191 for females, and TL=0.0086TW3.270 for the combined sexes. Egg diameter ranged from 0.8 to 1.8 mm with the mean of 1.259±0.50 mm. Mean absolute and relative fecundities were 2117±1243 eggs/female, and 130±77 eggs·g-1 body weight, respectively. Absolute fecundity and egg diameter were found to increase significantly with increasing fish size, whereas relative fecundity decreased significantly with total body weight.

Keywords: Sex ratio, Age, Growth, Reproduction, LWR, Miankaleh. Citation: Patimar, R.; Qaranjiki, A. & Bahalkeh, A. 2019. Life history traits of the Caspian stellate tadpole-goby Benthophilus leobergius Berg, 1949 (Teleostei: Gobiidae) from the southeastern Caspian Sea, Iran. Iranian Journal of Ichthyology 6(4): 254-263.

Introduction 1985, 1987; Stepanova 2001), knowledge of such The Caspian stellate tadpole-goby, Benthophilus factors in the Iranian waters is limited. There are only leobergius Berg, 1949 is a gobiid, endemic to the two available reports regarding to the biology of Caspian Sea basin (Ragimov 1986). Populations of B. leobergius in Iranian waters of the Caspian Sea this are found in both western and northern (Abdoli 2000; Naderi & Abdoli 2004). According to parts of the Caspian Sea, including the lower reaches the (IUCN) Red List of Threatened Species, this of the River up to Astrakhan (Kottelat & species does not appear in need of conservation, Freyhof 2007), but it is principally found in the east being categorised as of ‘Least Concern’. To the best (Ragimov 1965). Its range also encompasses many of our knowledge, data is deficient, however, for parts of the southern Caspian Sea, in Iranian portion some life history aspects of the species, including including the Gomishan Wetland and the Gorgan population trends over its range. Variations are Bay, which form a large part of the Miankaleh known to occur in certain life history characteristics Wildlife Refuge (Naderi & Abdoli 2004). Compared of fish populations of the same species living in with other gobiids known from the southern Caspian different regions. Several studies have demonstrated Sea, biological aspects of B. leobergius still remain such variations in response to environmental unstudied. While the distribution, morphological conditions (Roff 1982; Stearns 1992). As such, variation and life history parameters of this species examination of the basic biological parameters for have been widely documented in northern and each population is fundamental for understanding the western parts of the Caspian Sea (Ragimov 1978, species’ life history patterns and is important with

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Patimar et al.- Life history traits of Benthophilus leobergius

respect to implementing effective management and conservation measures for the species. In light of the habitat differences between the various regions of the Caspian Sea, we hypothesised that populations of this species inhabiting the southeastern Caspian Sea basin would differ in life history traits from those of the southwestern, western and northern regions. The aim of this study, therefore, is to represent the first detailed data on life history traits of the B. leobergius from the southeastern Caspian Sea.

Fig.1. The study area in the southeastern Caspian Sea, Materials and Methods Iran. The study area (Fig. 1) is situated along the Caspian Sea coast in the Miankaleh Wildlife Refuge. This calculated for each fish and mean values calculated refuge includes the Miankaleh Peninsula, the open for each sampling date. The ovaries of 65 ripe waters of Gorgan Bay and the marshes at the west females at maturity stage IV were used to estimate end of the bay. During October to April (every year) absolute (AF) and relative (RF) fecundities. The commercial beach seining takes place for Mugilids ovaries were removed, weighed and placed in (mullet) along the northern coast of the Caspian Sea. Gilson’s fluid for 3-4 days to harden the eggs and Seine netting is known to be a useful technique for dissolve the ovarian membranes. Absolute fecundity collecting fishes for biological samples, sampling was estimated using the gravimetric method, using fish diversity within a given habitat, and for three pieces removed from the anterior, medial and estimating relative species or population abundance. posterior of the ovary. Relative fecundity was A total of 256 specimens were collected from the calculated as RF = AF/TW (Bagenal & Tesch 1978). commercial catches during the fishing season in Mean egg diameter was examined by measuring 25- 2013, 2014 and 2015. All obtained specimens were 30 eggs taken randomly from the ovaries of the immediately preserved in 10% formaldehyde females used for fecundity determination. solution (after anaesthesia) for subsequent Measurements were made to the nearest 0.05 mm examination in the laboratory. using a microscope fitted with an ocular micrometer. In the laboratory, all specimens were measured Analysis of co-variance (ANCOVA) was performed for total length (TL), total body weight (TW) and to test for significant differences in weight-length gonad weight (to the nearest 0.01 g). Age was relationships between sexes. Any significant determined from both left and right otoliths; banding difference in the overall sex ratio was assessed using patterns being reviewed three times (each time by a the chi-square test (Zar 1984). Comparison of GSI different person) using a 20-30 binocular values between sexes was carried out by analysis of microscope under reflected light. The relationship variance (ANOVA). All statistical analyses were between TL and TW was determined using the performed with a significance level of P<0.05 using equation: TW = aTLb; where a is the intercept and b the SPSS 18 software package. is the slope (coefficient of allometry), as per Pauly (1984). Sexes were determined by visual Results examination of the gonad tissue. The gonadosomatic A total of 256 specimens of B. leobergius were index (GSI % = [gonad weight/TW]  100) was investigated including 94 males and 160 females (due 255 Iran. J. Ichthyol. (December 2019), 6(4): 254-263

Fig.2. Total length (mm) frequency of males and females of Benthophilus leobergius from southeast of the Caspian Sea, Iran. to unclear gonads, 2 specimens could not be sexed). The overall sex ratio was 1:1.70, with females significantly more prevalent than males (χ2=17.15, P<0.05). The maximum age in both sexes was 2+ years. Males ranged from 57 to 138 mm TL and 2.43 to 58.26 g TW, and females from 50 to 127 mm TL and 1.65 to 39.56 g TW. The most frequent size class in samples was 120-125 mm for males and 95-100 mm for females (Fig. 2). Females were absent from length classes >130 mm TL. The observed length-at-age differ between sexes (Table 1), with males longer and heavier than females (ANCOVA, FTL=33.12, FTW=24.31, P<0.05). Length-weight relationships were significant with high regression coefficients, the coefficients being significantly different between considered groups (Fig. 3). The slope values for b indicate a positive pattern of allometric growth (t-test, tmale=15.25, tfemale=11.31, tpopulation=12.89, P<0.05). GSI was significantly lower in males than females Fig.3. Relative growth curves (total length-total (ANOVA, F=148.24, P<0.05), with the highest mean weight) of males, females and sexes combined of value was observed in October (0.62±0.12) and April Benthophilus leobergius from the south-eastern (0.97±1.03) for males and in October (13.48±7.71) Caspian Sea, Iran. and March (10.19±7.88) for females. The ripe Oocytes ranged from 0.43 to 3.62 mm, with a specimens were observed in October and March, mean egg size of 1.259±0.50 mm. The majority of indicating the species has two reproductive periods in oocytes were 0.8 and 1.8 mm in size (Fig. 5). Egg this region, the first around October and the second diameter was positively correlated with both TL and around March-April (Fig. 4). 256 Patimar et al.- Life history traits of Benthophilus leobergius

Table 1. Mean total length-at-age ±SD (mm) for male and female Benthophilus leobergius from the southeastern Caspian Sea.

Male Female N TL±S.D W±S.D N TL±S.D W±S.D 0+ 1 57.00±--- 16.82±--- 27 67.93±8.94 4.94±2.07 1+ 91 105.82±13.13 23.47±13.13 129 103.89±8.78 18.30±7.39 2+ 2 137.50±0.71 57.62±0.89 4 125.89±8.78 32.37±4.97

Table 2. Length-weight relationship coefficients for gobiid species in the southern Caspian Sea.

Sex b-value Reference 1 Species Population 2.40

Ponticola gorlap Male 2.39 Abdoli et al. (2009) Female 2.588 Population 3.29

Neogobius pallasi Male 3.291 Abdoli et al. (2009) Female 2.92 Male 3.232 Neogobius pallasi Abdoli et al. (2002) Female 4.029 Male 3.623 Neogobius pallasi Alavi Yeganeh and Kalbasi (2006) Female 2.999 Male 3.31 Neogobius pallasi Allahyari (2008) Female 3.20 Male 2.96 Neogobius pallasi Patimar et al. (2008) Female 2.89 Population 3.08

Neogobius melanostomus Male 3.17 Abdoli et al. (2009) Female 2.70 Male 3.24 Neogobius melanostomus Allahyari (2008) Female 3.12 bathybius Population 2.44 Abdoli et al. (2009) Population 2.51

Knipowitschia caucasica Male 2.72 Abdoli et al. (2009) Female 1.97 Population 3.5 Ponticola syrman Male 3.41 Abdoli et al. (2009) Female 3.5 Male 3.27 Ponticola syrman Allahyari (2008) Female 3.78 Male 2.90 Knipowitschia caucasica Allahyari (2008) Female 2.99 Benthophilus leobergius Male 2.50 Abdoli et al. (2009) Population 3.27 Benthophilus leobergius Male 3.289 Present study Female 3.191

TW (Fig. 6). with 10.2 g in TW, and maximum AF was 5772 eggs, Minimum AF was 132 eggs, observed in a female observed in a specimen with 39.54 g in TW. Mean 257 Iran. J. Ichthyol. (December 2019), 6(4): 254-263

Fig.4. Monthly distribution of GSI of Benthophilus leobergius from the south-eastern Caspian Sea, Iran.

Fig.6. Monthly distribution of GSI of Benthophilus leobergius from the south-eastern Caspian Sea, Iran. Abdollah-Pour Biria et al. 2010), N. pallasi (Abdoli Fig.5. Size frequency distribution of the oocyte et al. 2002; Alavi Yeganeh & Kalbasi 2006; Ghothb- diameter of Benthophilus leobergius from the south- eastern Caspian Sea, Iran. Razmjoo et al. 2008; Patimar et al. 2008), P. syrman (Allahyari 2008), or N. caspius (Sarpanah et al. AF was 2117±1243 eggs per female. AF was found 2008). to increase significantly with increasing fish size During sampling, we observed that B. leobergius (Fig. 7). Mean RF was 130.20±77.02, ranging from occurred in low numbers at the sampling site. 13 to 360 eggs·g-1. Relative fecundity was found to According to Ragimov (1985) and Abdoli & Naderi decrease significantly with total body weight (Fig. 8). (2009), however, populations are also generally

found at low abundance in the east and southeast of Discussion the Caspian Sea basin. Overall, B. leobergius was No detailed data on the life history of B. leobergius found to occur at relatively low abundance, to be fast in Iranian waters of the southern Caspian Sea is growing and short lived (<2+ years for both sexes), available, though information is found for this and males exhibited a much wider range in length and species in the other parts of the Caspian Sea. For this a higher maximum length than females. Differences reason, it is difficult to describe the present biological in maximum length are not uncommonly observed status of the species in this region. This study between populations. In this case, B. leobergius from provides essential basic biological information of B. the southeastern Caspian Sea are larger than other leobergius in the southern Caspian Sea, which similar studied populations/areas, i.e. 110 mm TL (Naderi & data is widely available for some other gobiids in Iran Abdoli 2004) compared with 107 mm in the northern e.g. Neogobius melanostomus (Allahyari 2008; 258 Patimar et al.- Life history traits of Benthophilus leobergius

Table 3. Absolute fecundity of gobiid species in southern Caspian Sea. Species minimum AF maximum AF Average AF References Neogobius melanostomus 90 595 365 Allahyari (2008) Neogobius pallasi 320 1000 584 Allahyari (2008) Neogobius pallasi 184 1175 508 Patimar et al. (2008) Ponticola syrman 340 1250 --- Allahyari (2008) Knipowitschia caucasica 100 340 194 Allahyari (2008) Neogobius caspius 212 1234 Sarpanah et al. (2009) Benthophilus leobergius 132 5772 2117 Present study

Fig.8. Relationship between relative fecundity and fish total weight (g) in Benthophilus leobergius from the southeastern Caspian Sea-Iran. previously reported: 1+ in the southern Caspian Sea (Naderi & Abdoli 2004), and 18 months in both the northern (Berg 1965; Kottelat & Freyhof 2007) and western (Ragimov 1985) Caspian populations. The proportion of 2+ specimens in the southeastern sample was reasonably high, a pattern not observed in most other B. leobergius populations throughout its distribution range (i.e. in the southern and north- Fig.7. Relationship between absolute fecundity and western Caspian Sea basin). This could be interpreted fish total length (mm) and total weight (g) in Benthophilus leobergius from the southeastern as an inter-population pattern for the species. A Caspian Sea, Iran. comparison of gobiid species (Table 2) indicates that Caspian Sea (Berg 1965). Variations in maximum B. leobergius, along with Knipowitschia caucasica length can usually be explained by differences in (with a maximum age of 1+), is one of the shorter- food resources availability, individual growth rates, lived Caspian gobiids, with a lifespan not-exceeding natural selection processes and/or exploitation 2 years. patterns. As B. leobergius is not subject to The studied goby growth is positively allometric commercial exploitation, environmental conditions in the southeastern Caspian Sea, with differences are the likely source of the observed variations. between males and females explained by differences The observed maximum age for the south-eastern in the size distributions of the two sexes, which, in B. leobergius population is higher than that turn, reflects the differing influence of habitat factors on growth. Calculated b-values in this study differ 259 Iran. J. Ichthyol. (December 2019), 6(4): 254-263

from those found for the species in the southern females (as expressed by mean GSI value) was Caspian Sea (Abdoli et al. 2009), where negative significantly different from that of males (the GSI allometric growth was reported for males (b=2.50). value for females was 10-20 times higher than that The positive allometric growth observed for the for males at the peak of the reproduction period). species in the southeast concurs with the general Both of these factors represent important parameters growth pattern for gobiid species (Table 2). The in the reproductive strategy for this species. The different b-values observed between B. leobergius observed high variation in oocyte size within females sexes, as well as for those of some other gobiid of the studied B. leobergius population agrees with species, suggesting that the growth model may differ the hypothesis that there should be higher variation between sexes and species. Furthermore, differing b- in egg size in marine habitats due to selective values reflect a change in body form with sex and pressures from the presence of other fishes, and species, itself probably an effect of differing especially predators, i.e. an increased chance of environmental conditions and species characteristics. becoming prey and/or niche competition. While fish species would be expected to have a There is a widespread trend for fecundity in fishes sex ratio that did not differ significantly from unity to be positively correlated with length (Peters 1983). (i.e. 1:1), the predominance of one of the sexes is in This is primarily due to an increased amount of fact common in fish populations. For B. leobergius, energy available for egg production and the body the highly female dominated sex ratio could be due cavity accommodating eggs increasing in size as to a higher survival rate and/or greater longevity in overall fish size increases (Jonsson & Jonsson 1999). females. As longevity of the sexes was the same in In the present study, AF was positively correlated this B. leobergius population, the most direct with fish size (TL and TW), indicating that total hypothesis is that survival rate differs between the energetic investment in reproduction tended to sexes. The same high female dominance was also increase with fish size. The relationship between RF reported for K. caucasica and N. pallasi (Allahyari and fish weight was, however, negatively correlated, 2008), while male dominance was observed in implying that the proportional energetic investment N. melanostomus. Based on these results, the highly (i.e. energy allocation per unit of fish size) tended to female biased sex ratio for this B. leobergius decrease with increasing fish size. This is also population could be interpreted as a characteristic evident in the minimum and maximum values for AF feature of the species in the southeastern Caspian when compared with those reported by Ragimov Sea. (1985) for the Caspian Sea (590-2136 eggs), though GSI values for the southeastern B. leobergius B. leobergius in the southeastern Caspian Sea population indicate that this species has two demonstrated a wider range of AF values. This wide reproductive seasons, as has been reported for some variation in AF is believed to be not only due to other gobies in the area, e.g. N. melanostomus in the population characteristics but also to variation in Gomishan Wetlands (Allahyari 2008). Ragimov nutrition, food availability and ecological conditions (1985) reported similar timing in spawning (October- in the water bodies of the area. If differences in the December and March-April) for B. leobergius from AF of other gobiid species inhabiting the area are the southern Caspian Sea, but a different considered as inter-species variation, it is clear that reproductive season (April-May) for B. leobergius B. leobergius in the southeastern Caspian Sea is inhabiting the northern Caspian Sea. It appears, much more fecund than the other species (Table 3). therefore, that reproductive strategy (as expressed by It is possible that the higher number of eggs in GSI pattern) is significantly different among B. leobergius correlates with an increased mortality populations. Further, reproductive investment by rate for fry and fingerlings, i.e. a lower survival rate 260 Patimar et al.- Life history traits of Benthophilus leobergius

during the juvenile period. Inter-Gobiid species Scientific Translations Ltd, Jerusalem, (Russian variations in fecundity suggest that the southern version published 1949). 576 p. Caspian gobiid species follow different reproduction Bagenal, T. & Tesch, F. 1978. Age and growth. In: In: strategies. Bagenal, F. (ed), Methods for Assessment of Fish Production in Freshwaters. IBP Handbook 3, Blackwell Scientific Publications, Oxford. 256 p. Acknowledgments Ghothb-Razmjoo, E.; Rezvani, S.; Fatemi, S.M.R.; The authors thank local beach seine fishermen for Ghavam Mostafavi, P. & Purkazemi, M. 2008. field assistance and help with collections of fish Population genetic structure of Neogobius caspius samples. The authors also wish to thank the Gonbad (Eichwald, 1831) in the South Caspian Sea using Kavous University for financial support during this PCR-RFLP marker. Iranian Journal of Fisheries 2(3): study. 1-7. Jonsson, N. & Jonsson, J. 1999. Trade-off between egg References mass and egg number in brown trout. Journal of Fish Abdoli, A. 2000. The Inland Water Fishes of Iran. Biology 55: 767-783. Museum of Nature and Wild life, Tehran, Iran. 377 p. Kottelat, M. & Freyhof, J. 2007. Handbook of European Abdoli, A.; Rahmani, H. & Rasouli, P. 2002. On the Freshwater Fishes. Kottelat Cornol, Switzerland and occurrence, diet and reproduction of Neogobius Freyhof, Berlin. 646 p. fluviatilis in Madarsou stream, Golestan National Naderi, M. & Abdoli, A. 2004. Fish species Atlas of Park (north eastern Iran). Zoology in the Middle East south Caspian Sea Basin (Iranian waters). Iranian 26: 123-128. Fisheries Research Organization, Tehran. 242 p. Abdoli, A.; Allahyari, S.; Kiabi, B. H.; Patimar, R.; Patimar, R.; Mahdavi, M.J. & Adineh, H. 2008. Biology Ghelichi, A.; Mostafavi, H.; Aghili, S. M. & Rasooli, of sand goby Neogobius fluviatilis pallasi (Berg P. 2009. Length–weight relationships for seven 1916) in Zarrin-Gol River (east Alborz Mountain). Gobiid fish species in the southeastern Caspian Sea Journal of Agricultural Sciences and Natural basin, Iran. Journal of Applied Ichthyology 25: 785- Resources 15(1): 54-64. 786. Pauly, D. 1984. Fish Population Dynamics in Tropical Abdoli, A. & Naderi, M. 2009. Biodiversity of Fishes of waters: a Manual for Use for Programmable the Southern Basin of the Caspian Sea. Abzian Calculators. ICLARM Studies and Reviews 8. 325 p. Scientific Publication, Tehran. Peters, R. H. 1983. The Ecological Implications of Body Abdollah-Pour Biria, H.; Abbasi, K. & Sarpanah, A.N. Size. Cambridge University Press, Cambridge. 344 p. 2010. Studying diet of Neogobius melanostomus at Ragimov, D. B. 1965. On the distribution of gobiids in south west coast of Caspian Sea (Guilan Province). the western coast of the central and southern Caspian. Journal of Fisheries. Islamic Azad University, Dokladi Akademii Nauka Azerbaijana, SSR. 21(12): Azadshahr Branch 4(3): 15-27. 47-50. (In Russian) Alavi Yeganeh, M.S. & Kalbasi, M.R. 2006. Study on Ragimov, D.B. 1978. On the systematic status of some diet composition of Caspian sand goby, Neogobius species of the Benthophilus (Family Gobiidae) fluviatilis pallasi (Berg, 1916), in south of Caspian from the Caspian Sea and the Sea of Azov. Journal of Sea (Noor Beach). Iranian Journal of Biology 19(3): Ichthyology 18(5): 701-708. 180-190. Ragimov, D. B. 1985. Some Caspian species of the genus Allahyari, S. 2008. Investigation on age, growth, Benthophilus (Gobiidae). Journal of Ichthyology reproduction and feeding habits of gobiid species in 25(6): 153-161. Gomishan wetland. MSc. thesis, Shahid Beheshti Ragimov, D.B. 1986. Zoogeographical analysis of Universiy, Tehran, Iran. Gobiid fishes of Caspian Sea. In: Proceeding of 5th Berg, L.S. 1965. Freshwater fishes of the U.S.S.R. and Congress of Hydrobiological Association, Academy Adjacent Countries. Vol. II, 4th edn. Program for of Science of USSR, Taliatti. pp: 113-114.

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262 Iran. J. Ichthyol. (December 2019), 6(4): 254–263 Received: December 18, 2018 © 2019 Iranian Society of Ichthyology Accepted: June 1, 2019 P-ISSN: 2383-1561; E-ISSN: 2383-0964 doi: 10.22034/iji.v6i4.361 http://www.ijichthyol.org

مقاله پژوهشی تاریخچه زیستی مترسک ستارهای enthophilus leobergius Berg, 1949 درجنوب شرق دریای خزر

* رحمان پاتیمار ، عبدالصالح قرنجیکی، ارسالن بهلکه گروه شیالت، دانشکده منابع طبیعی، دانشگاه گنبد کاووس، گنبد کاووس، ایران.

چکیده: مترسک ستارهای دریای خزر بومزاد حوضه دریای خزر میباشد. در آبهای ایرانی دریای خزر اطالعات محدودی در مورد خصوصیات زیستی این گونه وجود دارد. جهت بررسی تاریخچه زیستی این گونه، 256 نمونه از سواحل جنوب شرق دریای خزر واقع در بخشهای شمالی پناهگاه حیات وحش میانکاله صید گردید. حداکثر سن جمعیت مورد مطالعه +2 سال بود. نسبت جنسی نر به ماده، 1:1.70 بهدست آمد. رابطه طول-وزن برای نرها TL=0/0088TW3/289، برای مادهها TL=0/0099TW3/191 و برای جمعیت TL=0/0086TW3/270 بود. میانگین قطر تخمکها 259/1 )5/0±( میلیمتر بهدست آمد که از 8/0 تا 8/1 میلیمتر متغیر بود. میانگین همآوری مطلق و نسبی بهترتیب )1234±( 2117 و )77±( 130 محاسبه گردید. همآوری مطلق و قطر تخمک همبستگی مستقیم و معنیداری را با اندازه ماهی نشان داد، در حالیکه همآوری نسبی بهطور معنیداری با افزایش اندازه ماهی کاهش داشت. کلماتکلیدی: نسبت جنسی، سن و رشد، تولیدمثل، رابطه طول و وزن، میانکاله.

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