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Liza macrolepis inhabits marine, estuarine, and fresh water throughout most tropical and temperate regions of the world. L. macrolepis were collected using samples caught by set net in the southwestern of Taiwan in this study. Length-weight and length-length, fork (FL), standard (SL), and total (TL) lengths relationships are derived, respectively. The relationships between lengths are all significantly linear (p < 0.001), the b value in the length-weight relationship for this value is significantly lower than 3 in the winter (p < 0.001), when the temporal changes are taken into account, indicating that only the sampling time affected the growth pattern of L. macrolepis. Growth is isometric in the spring, summer fall and, but it is negative and allometric in the winter.Key words: Liza macrolepis, Length-Weight relationship (LWR), growth.

Spotted catfish is a benthic species that can be found abundantly off the coast of Yunlin in southwestern Taiwan. Its biological parameters are little known. In this study, life history parameters of this species were estimated using samples caught by bottom trawling. The spotted catfish was the major bycatch species which comprised 32% of the total catch. The growth parameters estimated by length frequency analysis were: asymptotic fork length (L∞ = 34.4 cm), growth constant (k = 0.28 year-1) and age at length 0 (t0 = -0.57 year-1). The total mortality, natural mortality, fishing mortality and the exploitation ratio were 1.29, 0.86, 0.43 year-1 and 0.24, respectively. Although spotted catfish is not a target species of bottom trawling, the high fishing mortality and exploitation ratio suggest that they are the major by-catch species, and hence more attention should be paid to the dynamics of this stock. According to the monthly length distribution, the smallest fish (median = 2 cm) appeared in July 2009, which implies that the spawning season of spotted catfish is in June or July. However, the results of this study are preliminary, therefore other methods, such as ring reading of hard tissue, should be utilized to verify the growth parameters of spotted catfish.Key words: Age and growth, mortality, exploitation rate, spotted catfish

Length-weight relationships are presented for 24 fish species representing 12 families captured monthly from February 2009 to March 2010, off the southwestern coast of Taiwan. 12 of these species are documented in fishbase, but no length-weight relationships were available. One record of maximum length was recorded. Among all estimated parameter b of 24 species, there was significant difference of 3 for 15 species. Compared length-weight relationships with previous studies, the trends were obviously different.Key words: Length-weight, fish species, fishbase.