Length–weight relationships for 21 fish species (Actinopterygii) from southeastern Gyeongsangnam-do, South Korea

Length–weight relationships (LWR) were estimated for 21 fish species sampled from southeastern Gyeongsangnam-do, South Korea, including the Ulju basin (Yangsan and Hoeya rivers) and the Miryang River system (Miryang River and Danjang Stream). The following species were studied: Carassius auratus (Linnaeus, 1758); Rhodeus uyekii (Mori, 1935); Acheilognathus majusculus Kim et Yang, 1998; Pseudorasbora parva (Temminck et Schlegel, 1846); Pungtungia herzi Herzenstein, 1892; Coreoleuciscus aeruginos Song et Bang, 2015; Squalidus multimaculatus Hosoya et Jeon, 1984; Rhynchocypris oxycephala (Sauvage et Dabry de Thiersant, 1874); Zacco platypus (Temminck et Schlegel, 1846); Misgurnus mizolepis Günther, 1888; Koreocobitis naktongensis Kim, Park et Nalbant, 2000; Iksookimia longicorpa (Kim, Choi et Nalbant, 1976); Niwaella multifasciata (Wakiya et Mori, 1929); Liobagrus mediadiposalis Mori, 1936; Oryzias latipes (Temminck et Schlegel, 1846); Coreoperca herzi Herzenstein, 1896; Lepomis macrochirus Rafinesque, 1819; Micropterus salmoides (Lacepède, 1802); Odontobutis platycephala Iwata et Jeon, 1985; Odontobutis interruptus Iwata et Jeon, 1985; Acanthogobius flavimanus (Temminck et Schlegel, 1845). LWR data for four species, have not previously been reported in FishBase ( A. majusculus , K. naktongensis , N. multifasciata , L. mediadiposalis ) while those for 12 additional species were available in limited numbers (1–4 records). Among species with sufficient sample sizes ( n ≥ 20), six species exhibited negative allometric growth ( b < 3) and one showed isometric growth ( b ≈ 3). The values of coefficient a ranged from 0.0020 to 0.0166. For species with n ≥ 20, b ranged from 2.80 to 3.03; for species with n < 20, b was fixed at 3.0. All species showed high correlation coefficients ( r 2 > 0.95).