Fish Composition and Diversity of Four Coral Reefs in the South China Sea Based on Hand-Line Catch

Abstract

To improve the overall understanding of the fish diversity and spatial patterns of major coral reefs in the South China Sea, fish assemblage composition, dominant species, biodiversity indices, and multivariate analysis of community structure were reported for four major coral reefs based on hand-line survey data in May and September 2018. A total of five orders, 21 families, 45 genera and 121 species of fish were recorded with Perciformes (78.5%) being the most diverse. The highest number (5) of dominant species was found near Chenhang Island while the lowest (2) number was detected at Zhubi Reef. The highest abundance index (7.21) occurred at Zhubi Reef, while the Shannon–Wiener diversity (4.80), Pielou’s evenness (0.81), and Simpson’s dominance (0.95) indexes were all highest at Qiliangyu Island. Based on cluster analysis and non-metric multi-dimensional scaling (NMDS), fish communities varied more spatially than seasonally. Our results led us to hypothesize that the habitat complexity and level of anthropogenic disturbance were the main factors affecting the composition of reef-dwelling fish on each coral reef. Topography was likely responsible for most variation in the spatial pattern of fish diversity.

Distribution Pattern of Coral Reef Fishes in China

“…Therefore, it could be speculated that the coral reef area in China is the main activity area of coral reef fishes between the Indian and Pacific Oceans. According to the "Island Effect" theory, coral reef species diversity is closely related to coral reef cover area, a well-known concept in coral reef ecology [30]. The total area of coral reefs in the South China Sea is approximately 3 × 10 4 km 2 , accounting for 5% of the global coral reef area (60 × 10 4 km 2 ) [28,47].…”

“…This may be because the coral reefs in China are located on the northern edge of the "coral triangle" with low latitude and high temperature and affected by the cold flow of the mainland's estuary and the South China Sea tropical warm currents, forming a unique coral reef ecosystem that integrates multiple physical, chemical, geological, energy, and material flow properties [28]. Many studies have shown that the composition of coral reef fishes is closely related to the status of coral reefs, human interference, environmental factors, and sampling time and methods [27,30,[51][52][53].…”

“…The following supporting information can be downloaded at: https: //www.mdpi.com/article/10.3390/su142215107/s1, Table S1: The Checklist of coral reef fishes in China. References [30,63,77, are cited in the Supplementary Materials.…”

“…Strona et al [29] proposed that if corals disappear, the global tropical reef fish biomass will be reduced by half. Coral die-off and bleaching may reduce the environmental carrying capacity of coral reef ecosystems, and coral reef fishes may adapt to habitat changes by changing their community structure [30]. As a result, the diversity of coral reef fishes is reduced or even lost, which has led to countless direct or indirect nutritional relationships, ecosystem functions and services, and other effects [31].…”

Long-term variations in trophic groups of coral reef fishes in the lagoon of Meiji Reef in the South China Sea

“…rising ocean temperature and unsustainable fishing (Allgeier et al, 2016;Hughes et al, 2017;Munday et al, 2008). The South China Sea (SCS) is a globally significant area because of its shallow coral reefs and high biodiversity (Chen and Li, 2005;Arai, 2015;Lu et al, 2021;Dai et al, 2022;Li et al, 2022). Under multiple stressors of human activities and climate change, the coral cover in the SCS has severely declined within the past few decades, and coral reef fish populations have receded (Hughes et al, 2013;Zhao et al, 2013;Zhao et al, 2016;Hughes et al, 2017;Zhang et al, 2021a;Zhang et al, 2021b).…”