Dietary Composition and Trophic Niche Partitioning of Spotty‐bellied Greenlings Hexagrammos agrammus, Fat Greenlings H. otakii, Korean Rockfish Sebastes schlegelii, and Japanese Seaperch Lateolabrax japonicus in the Yellow Sea Revealed by Stomach Content Analysis and Stable Isotope Analysis

Abstract

Stable nitrogen and carbon isotope ratios of fish tissues, in combination with stomach content analysis, provide insights into how energy flows through marine food webs. Using these techniques, we investigated the diets and trophic niches of four important fish species of the Yellow Sea: the Spotty‐bellied Greenling Hexagrammos agrammus, Fat Greenling H. otakii, Korean Rockfish Sebastes schlegelii, and Japanese Seaperch Lateolabrax japonicus. The stomach content analysis revealed that Spotty‐bellied Greenlings mainly fed on crabs and fish; Fat Greenlings mainly preyed on fish, crabs, and shrimps; Korean Rockfish primarily consumed fish and shrimps; and Japanese Seaperch mainly fed on fish. Korean Rockfish had the highest dietary breadth index among the four fish species. Dietary composition of the four species did not overlap significantly, as indicated by Schoener's index. Prey category composition varied across fish species and differed between species pairs (except Korean Rockfish and Japanese Seaperch), as suggested by permutational ANOVA tests. The stable isotope analysis suggested that Japanese Seaperch had significantly higher δ13C and δ15N and had a significantly different centroid position, both of which indicated a higher trophic position. The corrected standard ellipse area on the δ15N–δ13C (‰) biplot varied in size among species and significantly overlapped in the three rockfishes, with the largest overlap area observed between Fat Greenlings and Korean Rockfish. The results, in general, suggested that the three rockfish species, especially Korean Rockfish and Fat Greenlings, had similar trophic niches, but they were partitioned by prey resources according to the stomach content composition. Our study provides novel insights into the dietary niches and trophic dynamics of these four exploited species, which could help to improve ecosystem‐based fisheries management in the Yellow Sea.

Trophic interactions of reef-associated predatory fishes (Hexagrammos otakii and Sebastes schlegelii) in natural and artificial reefs along the coast of North Yellow Sea, China

“…Decapods were observed to be most selected for by H. otakii at both sites, even though proportion of the diet represented by prey items within this category varied by habitat types, while S. schlegelii displayed a largely dependence of Gobiidae and Blenniidae irrelevant to habitat types. Our result is consistent with previous studies on trophic ecology of H. otakii and S. schlegelii, reporting that these two species were both shrimp and fish feeders, where H. otakii preyed more on Decapod while S. schlegelii relied more on teleosts (Kwak et al, 2005;Wu et al, 2018;Zhang et al, 2018).…”

“…Based on GCA, both species displayed diverse feeding choices, with at least 28 prey items identified in H. otakii and 21 in S. schlegelii, supporting the conclusion that they are opportunistic carnivorous predators (Wu et al, 2018;Zhang et al, 2018). Decapods were observed to be most selected for by H. otakii at both sites, even though proportion of the diet represented by prey items within this category varied by habitat types, while S. schlegelii displayed a largely dependence of Gobiidae and Blenniidae irrelevant to habitat types.…”

“…The MixSIAR model allows for uncertainties associated with isotopic signatures and diet-to-tissue discrimination factors (Parnell et al, 2010;Phillips et al, 2014), which were set 1 ± 0.1‰ and 3.4 ± 0.11‰ for 13 C and 15 N respectively as recommended in Post (2002). Food items used in the model was derived from GCA, as well as a prior knowledge about their feeding preferences (Kwak et al, 2005;Zhang et al, 2014Zhang et al, , 2018Wu et al, 2018).…”

“…Development of artificial reefs has been increasingly carried out in the Yellow Sea coast as one of the major restoration approaches to support the fish living. Although the feeding ecology of both H. otakii and S. schlegelii in artificial reefs in Yellow sea, China have been reported in a few previous researches (Wu et al, 2018;Zhang et al, 2018). Trophic interaction between the two species with similar trophic level has yet been addressed.…”

Trophic relationships among fourteen native and non-native fish species in the Shatt Al-Arab River, Iraq

“…Braga et al [3] stated that the fish feeding ecology is thoroughly linked to population dynamics and has important implications in the subjects of resource partitioning, habitat preferences, prey selection, interspecific competition, and energy transfer within the ecosystem. Niche overlap and partitioning should provide very useful information on how these species rank in the food web to derive implications for fisheries management [4].…”