Lengthweight Relationships of Fishes in the Wu Jiao Nature Reserve And

Technical Contribution Length-weight relationships of ﬁshes in the Wu Jiao nature reserve and adjacent areas, China By Y. Zeng1,2,3, Y.-Y. Huang2, Y.-B. Chen1 and Z.-J. Li3

1China Three Gorges Corporation, Beijing, China; 2Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), College of Life Science, China West Normal University, Nanchong, Sichuan Province, China; 3State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, China

Summary from the log transformed values of length and weight, i.e. = + * The length-weight relationships LWRs) (W = aLb) of four log10W log10(a) b log10(L), via least square linear regres- fish species caught in 2010–2012 from the Wujiao Nature sion (Zar, 1984). The main food of these fish were summa- Reserve and adjacent areas are reported. LWRs of these spe- rized from the research literature (Huang et al., 2002; Deng cies are documented for the first time. et al., 2010); when the diets of the species could not be found in the literature, its congeners or closely related taxon were used (FLIH, 1976). Introduction Wujiao Nature Reserve (103°590–104°240E/32°530–33°130N) is Results located in Jiuzhaigou County, in the north of Sichuan, a province in southwestern China. The present work reports Results are shown in Table 1, providing the length range of LWRs and main food items for four fish species in the the species covered and the respective length-weight relation- Wujiao Nature Reserve and the adjacent area. ships. For most species the length range covered is smaller than the known maximum length of the species, except for Schizopygopsis kialingensis. The ‘b’ values of the relation- Materials and methods ships are below 3, which seems to be typical for the shape of In total 225 fish specimens were collected from six sites in these small-sized fish. the town of Wujiao Nature Reserve along the main river and adjacent areas (103°590–104°240E; 32°530–33°130N); sampling Discussion took place from November 2010 to May 2012. Fish specimens were caught by hand-net and immediately sorted No LWR information was available in FishBase (Froese according to species. Total body weight of each specimen and Pauly, 2013) for the four species, which are reported was measured with an electronic scale (TP-A500, 0.01 g) to here for the first time. Among them, the maximum length the nearest 0.01 g. Standard length (SL) was measured to the of Schizopygopsis kialingensis in our study is 183.0 mm nearest mm. The values of constants a and b were estimated (70.20 g weight), which is more than the maximum length

Table 1 Length-weight regression parameters of four native ﬁsh species caught in Wujiao Nature Resources having no LWRs as described by Froese and Pauly (2013) in FishBase

Standard length Order and species N range (cm) a (95% CI) b (95% CI) r2 Main food

Cypriniformes Schizothorax prenanti 22 6.9–14.4 0.0234 (0.0105, 0.0513) 2.89 (2.58, 3.19) 0.95 Attached algae Schizopygopsis kialingensis 17 6.2–18.3 0.0275 (0.0120, 0.0646) 2.68 (2.35, 3.01) 0.95 Attached algae with little aquatic insects Triplophysa robusta 152 5.0–12.8 0.0237 (0.0147, 0.0380) 2.61 (2.40, 2.82) 0.94 Aquatic insects and benthic invertebrates Siluriformes Euchiloglanis kishinouyei 25 6.30–14.10 0.0224 (0.0132, 0.0389) 2.85 (2.61, 3.09) 0.96 Aquatic insects

U.S. Copyright Clearance Centre Code Statement: 0175-8659/2014/3005–1099$15.00/0 1100 Y. Zeng et al. record in Fishbase. The range of values for the coefficient References 2 of determination (r ) of the LWR was closer to or greater Deng, H.; Yue, X.; Chen, D.; Tian, H.; Liu, S., 2010: Growth char- than 0.94, demonstrating that the line-of-best fit to describe acteristics and feed habit of Triplophysa stenura in Nujiang the LWR explains at least 94% of the variation in fish River. Freshw. Fish. 40,26–33. – weight, and therefore the LWR may be applied to any Filiz, H.; Bilge, G., 2004: Length weight relationships of 24 fish species from the North Aegean Sea, Turkey. J. Appl. Ichthyol. 20, 431–432. length value to predict the weight within the range of fish Fish Laboratory of Institute Hydrobiology of Hubei Province (FLIH), lengths sampled (Garcia, 2010). In fisheries biology, fish 1976: Fishes in the Yangtze river. Science Press, Beijing. LWRs can also supply information to estimate the produc- Froese, R., 2006: Cube law, condition factor, and weight-length relation and biomass of a fish population when only length tionships: history, meta-analysis and recommendations. J. Appl. Ichthyol. 22, 241–253. measurements are available (Filiz and Bilge, 2004; Froese, Froese, R.; Pauly, D. (Eds). 2013: FishBase. World Wide Web elec- 2006; Wang et al., 2012). In addition, according to their tronic publication. Available at: http://www.fishbase.org,version main food items, these fish feed largely on attached algae (accessed on 24 December 2013). or aquatic insects and benthic invertebrates. The present Garcia, L. M. B., 2010: Species composition and length-weight rela- study provides baseline information on LWRs and main tionship of fishes in the Candaba wetland on Luzon Island, Phil- ippines. J. Appl. Ichthyol. 26, 946–968. food items for these fish in the Wujiao Nature Reserve and Huang, J.; Wang, C.; Zhao, G., 2002: Reproduction environment, adjacent area, which will be useful for researchers and sexual system and reproduction behavior of Euchiloglanis kish- fishery managers in the future. inouyei Kimura. Southwest Chin. J. Agricult. Sci. 16, 119–121. Wang, T.; Wang, H. S.; Sun, G. W.; Huang, D.; Shen, J. H., 2012: Length–weight and length–length relationships for some Yangtze – Acknowledgements River fishes in Tian-e-zhou Oxbow. J. Appl. Ichthyol. 28, 660 662. Zar, J. H., 1984: Biostatistical analysis. Prentice-Hall, Englewood This research was supported by the Foundation of the Sichu- Cliffs, NJ. an Province Education Department (No. 13ZB0014), the Author’s address: Yu Zeng, 1 Shi-da Road, Shunqing district, Nan- National Natural Science Foundation of China (No. chong, Sichuan Province 637002, China. 51309196), and the Innovative Team Foundation of China E-mail: [email protected] West Normal University.