Technical contribution Length-weight and length-length relationships of the genus Alosa (Clupeoidei: Clupeiformes: Clupeidae) along the southern Caspian Sea coast By H. Mousavi-Sabet 1 , A. Heidari 1 and S. Paknejad 2 1 Department of Fisheries, Faculty of Natural Resources, University of Guilan, Sowmeh Sara, Iran; 2 Department of Fisheries, Tonekabon Branch, Islamic Azad University, Mazandaran, Iran Summary Length–weight (LWR) and length–length (LLR) relation- ships were estimated for four shad species of the genus Alosa, reported from along the southern Caspian Sea coast, north of Iran in a study from March 2014. Two of these spe- cies are endemic to the Caspian Sea. The length–weight parameter b for these species ranged from 2.99 to 3.24, with regression coefficients (r 2 ) ranging from 0.91 to 0.99. All LLRs were highly significant (r 2 > 0.96). Introduction The genus Alosa along the southern Caspian Sea consist of four species: A. braschnikowi (Borodin, 1904), A. caspia cas- pia (Eichwald, 1838), A. kessleri (Grimm, 1887) and A. saposchnikowii (Grimm, 1887). Alosa braschnikowi and A. caspia caspia are endemic to the Caspian Sea (Afraei- Bandpyi et al., 2004). Fish LWRs are useful in determining weight and biomass and allow comparisons of species growth between different habitats, and is also required in fishery management and conservation (Moutopoulos and Stergiou, 2002; Oscoz et al., 2005; Mousavi-Sabet et al., 2015). The LLR S are used to convert length measurements from one length-type into another (Moutopoulos and Ster- giou, 2002). There is no published data on their general biology includ- ing LWR and LLRs for Alosa species along the southern Caspian Sea, and no corresponding data for A. braschnikowi is yet available in the FishBase database (Froese and Pauly, 2015). The principal aim of this paper was to provide the first comprehensive description of LWR and LLRs for all reported shad fishes, genus Alosa, along the southern part of the Caspian Sea. Materials and methods The study was conducted along the southern Caspian Sea coast, north of Iran. A total of 375 fishes were randomly col- lected in March 2014 by beach seine from six fishing areas from east to west, respectively: Miankaleh (36°54 0 10.89″N, 53°48 0 48.33″E), Sari (36°48 0 04.63″N, 53°02 0 07.50″E), Tonek- abon (36°50 0 20.97″N, 50°50 0 17.25″E), Anzali (37°29 0 29.86″N, 49°27 0 39.59″E), Rezvanshahr (37°36 0 32.19″N, 49°08 0 25.54″E), and Astara (38°23 0 47.40″N, 48°54 0 10.17″E). Total (TL), fork (FL) and standard (SL) lengths (1.0 mm) and body weight (0.1 g) were recorded for each fish. The statistical signifi- cance level of r 2 was estimated by linear regression on the transformed equation, log W = log a + b log L relationship. Where: a is the intercept and b is the slope of the linear regression (Koutrakis and Tsikliras, 2003; Froese, 2006; Froese and Pauly, 2015). The degree of relationship between the variables was computed by coefficient of determination (r 2 ). All statistical analyses were evaluated at p < 0.05 signifi- cance levels. Additionally, 95% confidence limits (CL) of a and b were estimated. Outliers observed in the log–log plots of all species were excluded from the regression (Froese, 2006; Froese et al., 2011). Results Descriptive statistics and estimated parameters of the LWR are given in Table 1. The b values in the LWR ranged from Table 1 Descriptive statistics and estimated parameters of LWRs for four Alosa species collected in studied areas, March 2014 Species Total length range [cm] Body weight range [g] N a 95% CI a b 95% CI of b r 2 SE b Alosa braschnikowi (Borodin, 1904) 19.9–40.0 46–582 170 0.00365 0.00103–0.01445 3.24 3.08–3.40 0.91 0.08 Alosa caspia caspia (Eichwald, 1838) 25.1–28.9 83–129 60 0.00368 0.00080–0.01663 3.12 2.93–3.31 0.99 0.07 Alosa kessleri (Grimm, 1887) 20.0–38.4 48–482 70 0.01890 0.00550–0.06530 3.13 2.95–3.32 0.98 0.09 Alosa saposchnikowii (Grimm, 1887) 20.7–37.2 70–398 75 0.01590 0.00450–0.05570 2.99 2.81–3.17 0.97 0.09 SE b = standard error b,N = sample size; a and b, length–weight relationship parameters, r 2 = coefficient of determination. U.S. Copyright Clearance Centre Code Statement: 0175-8659/2016/3201–129$15.00/0 J. Appl. Ichthyol. 32 (2016), 129–130 © 2015 Blackwell Verlag GmbH ISSN 0175–8659 Received: November 23, 2014 Accepted: April 22, 2015 doi: 10.1111/jai.12908 Applied Ichthyology Journal of