Trophic niche diversity and redundancy across trophic positions in a subtropical river fish assemblage

Authors: Zhang, Y., Li, J., Li, Y., Tarkan, A.S., Liu, C. and Britton, J.R.

Journal: Hydrobiologia

Volume: 851

Issue: 10

Pages: 2417-2428

eISSN: 1573-5117

ISSN: 0018-8158

DOI: 10.1007/s10750-023-05467-1

Abstract:

Understanding consumer–resource interactions is essential for understanding the trophic dynamics of species-rich fish communities. Woodland et al. (Oikos 125:556–565, 2016) assumed that trophic position (TP) distributions of primary consumers and tertiary species are restricted versus intermediate consumers tending to be omnivores with broader TP distribution, where these omnivores often dominate the overall biomass. With rare evidence supporting this hypothesis in a river, we tested it in the species-rich Pearl River fish assemblage, China. Using bulk stable isotope (SI) approach (δ13C, δ15N), the TPs, SI distribution parameters, isotopic niche sizes (as standard ellipse areas, SEA) and interspecific niche overlap were calculated for the abundant fish species. Fishes of intermediate TPs (i.e. omnivores) had larger δ13C variance/ range, broader isotopic niches and higher niche overlap compared to fishes at low TPs and high TPs, indicating a higher degree of trophic redundancy among the omnivores, whereas high TP fish had narrower niche and lower niche overlap, indicating trophic partitioning among tertiary species. These omnivores at intermediate TPs between 2.4 and 2.8 dominated fish biomass. The results not only support the Woodland et al. (Oikos 125:556–565, 2016) hypothesis in the river, but also provide a novel explaining in how niche sizes and overlap vary by TP.

Source: Scopus

Trophic niche diversity and redundancy across trophic positions in a subtropical river fish assemblage

Authors: Zhang, Y., Li, J., Li, Y., Tarkan, A.S., Liu, C. and Britton, J.R.

Journal: HYDROBIOLOGIA

Volume: 851

Issue: 10

Pages: 2417-2428

eISSN: 1573-5117

ISSN: 0018-8158

DOI: 10.1007/s10750-023-05467-1

Source: Web of Science (Lite)

Trophic niche diversity and redundancy across trophic positions in a subtropical river fish assemblage

Authors: Zhang, Y., Li, J., Li, Y., Tarkan, A.S., Liu, C. and Britton, J.

Journal: Hydrobiologia: the international journal on limnology and marine sciences

Publisher: Kluwer Academic Publishers

ISSN: 0018-8158

DOI: 10.1007/s10750-023-05467-1

Abstract:

Understanding consumer–resource interactions is essential for understanding the trophic dynamics of species-rich fish communities. Woodland et al. (Oikos 125:556–565, 2016) assumed that trophic position (TP) distributions of primary consumers and tertiary species are restricted versus intermediate consumers tending to be omnivores with broader TP distribution, where these omnivores often dominate the overall biomass. With rare evidence supporting this hypothesis in a river, we tested it in the species-rich Pearl River fish assemblage, China.

Using bulk stable isotope (SI) approach (δ13C, δ15N), the TPs, SI distribution parameters, isotopic niche sizes (as standard ellipse areas, SEA) and interspecific niche overlap were calculated for the abundant fish species. Fishes of intermediate TPs (i.e. omnivores) had larger δ13C variance/ range, broader isotopic niches and higher niche overlap compared to fishes at low TPs and high TPs, indicating a higher degree of trophic redundancy among the omnivores, whereas high TP fish had narrower niche and lower niche overlap, indicating trophic partitioning among tertiary species. These omnivores at intermediate TPs between 2.4 and 2.8 dominated fish biomass. The results not only support the Woodland et al. (Oikos 125:556–565, 2016) hypothesis in the river, but also provide a novel explaining in how niche sizes and overlap vary by TP.

Source: Manual