Isotopic niche overlap of two planktivorous fish in southern China

• DOI: 10.1007/s10201-010-0332-2
• Publication Date: 2010-09-14T04:47:15Z
• Authors: Gang Chen; Zaohe Wu; Binhe Gu; Dongyan Liu; Xin Li; Yang Wang
• Keywords: Bighead carp; Hypophthalmichthys; Isotope Analysis

The purpose of this study was to assess if there was trophic niche overlap of silver carp (Hypophthalmichthys molitrix) and bighead carp (H. nobilis) in four large freshwater ecosystems from southern China using stable carbon and nitrogen isotopes (δ13C and δ15N). Multivariate analysis of variance (MANOVA) on the δ13C and δ15N values measured from muscle tissue indicates trophic niche overlap in one unproductive and one highly productive large system and trophic niche segregation in two systems with moderate watershed size and productivity. For these two coexisting planktivorous fish, which were hitherto believed to occupy different trophic niches, this study demonstrated that the degree of their trophic niche overlap varied according to ecosystem properties.