Technical contribution Weight–length relationship of 63 demersal fishes on the shallow coast of Parana´, Brazil By A. C. Passos 1 , R. Schwarz Jr 2 , B. F. C. Cartagena 3 , A. S. Garcia 1 and H. L. Spach 1 1 Universidade Federal do Parana ´, Centro de Estudos do Mar, Depto. de Cieˆncias da Terra, Pontal do Parana ´, PR, Brasil; 2 Universidade Federal de Sergipe, Nu ´cleo de Engenharia de Pesca Centro de Cie ˆncias Biolo ´gicas e da Sau ´de Cidade Universita ´ria Prof. Jose´ Aloı´sio de Campos, Jardim Rosa Elze Sa ˜o Cristo ´va ˜o, Sergipe, Brasil; 3 Timbo ´ ⁄ SC, Brasil Summary This work presents the weight–length relationship of 63 species of fish belonging to 24 families. Data were collected monthly along the Parana´ state coast (Brazil) from August 2004 to July 2005 on five transects between 6 and 15 m. Several of these species had no previously published weight–length relation- ships. Introduction Weight–length relationships are used by researchers to esti- mate weight from a given length (Froese, 2006). The objective of the present study was to establish the weight–length relationships for 63 fish species from the shallow continental shelf of the Parana´ state coast (Brazil). The continental shelf of the Parana´ state coast is character- ized, for the most part, by a covering of sand, mud and clay (Matsuura, 1986). According to Figueiredo (1981), the Parana´ state coast contains the southern boundaries of tropical species distribution, the northern boundaries of temperate forms and a series of endemic species. Materials and methods Four 15-min bottom trawls on five transects were carried out monthly parallel to the coast at depths of 6, 9, 12 and 15 m (25 ° 20¢⁄ 48 ° 07¢; 25 ° 46¢⁄ 48 ° 30¢). Sampling was conducted using two commercial trawl nets. Fish from each sample were packed in labeled plastic bags and taken to the fish biology laboratory of the Centro de Estudos do Mar – UFPR for analysis. They were identified to the species level according to Figueiredo (1977), Figueiredo and Menezes (1978, 1980, 2000), Menezes and Figueiredo (1980, 1985) and Menezes et al. (2003). The species in this study were reviewed as regards the taxonomic classification and the nomenclature based on FishBase. Total length (cm) (from the tip of the snout to the end of the caudal fin), standard length (cm) (from the tip of the snout to the end of the vertebral column) and weight (g) data were obtained from each specimen (sample chosen randomly and up to a maximum of 30 samples per species). The presence of outliers for each species that presented nine or more captured fish (66 species) was verified using total length (TL) and weight (W) data (log-transformed and plotted graphically) (Giacalone et al., 2010). Species in which the number of captured fish was fewer than nine after the exclusion of the outliers were excluded from the analyses, with 63 species distributed in 24 families remaining. The adopted model was: (log W = log a + b*log TL), where W is the weight in grams, TL the total length in centimeters, a the constant and b the allometric coefficient (King, 1995; Froese, 2006). These last two values were estimated using a linear regression analysis (program Excel, 2007) (Giacalone et al., 2010). Results and discussion A total of 23 654 fish was analyzed (Table 1). They belonged to 63 species, nine of which (Anchoa spinifer, Aspistor luniscutis, Narcine brasiliensis, Oligoplites saliens, Ophioscion punctatissimus, Rypticus randalli, Rhinobatos percellens, Tri- nects microphthalmus and Zapteryx brevirostris) had no weight-length data recorded in FishBase or in the literature. The extreme b-values may be caused by narrow length- ranges (Citharichthys spilopterus and Anchoa lyolepis), or where there were only juveniles (Cynoscion leiarchus and Selene setapinnis). Comparing the obtained b-values with published values (3.135 ± 0.050 for C. spilopterus, 3.101 ± 0.121 for A. lyolepis, 2.872 ± 0.019 for C. leiarchus and 2.796 ± 0.016 for S. setapinnis; Joyeux et al., 2009; Muto et al., 2000), it is important to emphasize that these LWR estimates in particular should not be used outside the length range given. Acknowledgements The authors thank H.A. Pichler, S.B. Stoiev, C. Bernardo, L.O. Santos, G.M.L.N. Queiroz and C. Santos for assistance in field collections and laboratory analyses. A.C. Passos and R. Schwarz Jr. acknowledge financial support by the CAPES. References Figueiredo, J. L., 1977: Manual de Peixes Marinhos do Sudeste do Brasil. I. Introduc¸a˜ o. Cac¸o˜ es, raias e quimeras. Museu de Zoologia da Universidade de Sa˜o Paulo, Sa˜o Paulo, 104p. (in Portuguese) Figueiredo, J. L., 1981: Estudo das distribuic¸o˜es endeˆmicas de peixes da Provı´ncia Zoogeogra´fica Marinha Argentina. Tese apresent- ada ao Instituto de Biocieˆ ncias da USP, Sa˜o Paulo, 121p. (in Portuguese). J. Appl. Ichthyol. 28 (2012), 845–847 Ó 2012 Blackwell Verlag, Berlin ISSN 0175–8659 Received: December 13, 2011 Accepted: January 29, 2012 doi: 10.1111/j.1439-0426.2012.01973.x U.S. Copyright Clearance Centre Code Statement: 0175–8659/2012/2805–0845$15.00/0 Applied Ichthyology Journal of