Biogeography of functional trait diversity in the Taiwanese reef fish fauna

Abstract

The richness of Taiwanese reef fish species is inversely correlated to latitude as a direct consequence of the abiotic environment and its effects on benthic habitats. However, to date, no studies have investigated the variations in the diversity of traits (FD) linked with the role of these fishes in the ecosystem. FD is usually considered more sensitive than species richness in detecting early changes in response to disturbances, and therefore could serve as an indicator of ecological resilience to environmental changes. Here, we aim to characterize FD in the Taiwanese reef fish fauna and to document its regional variations. Six traits were used to categorize the 1,484 reef fish species occurring in four environmentally contrasted regions around Taiwan. The number of unique trait combinations (FEs), their richness (FRic), their redundancy (FR), their over‐redundancy (FOR), and their vulnerability (FV) were compared among these regions. Overall, 416 FEs were identified. Their number decreased from south to north in step with regional species richness but FRic remained similar among regions. FR and FOR were higher to the south. At the local scale, variations in FEs and FRic are in concordance with the worldwide pattern of FD. High‐latitude, impoverished fish assemblages, offer a range of trait combinations similar to diversified tropical assemblages. Increasing diversity in the latter mainly contributes to raising FR and supports already over‐redundant entities. High vulnerability makes many combinations highly sensitive to species loss, and was higher at intermediate latitudes when using a fine resolution in trait categories. It suggests that the loss of FEs may first be characterized by an increase in their vulnerability, a pattern that could have been overlooked in previous global scale analyses. Overall, this study provides new insights into reef fish trait biogeography with potential ramifications for ecosystem functioning.

Habitat change and its consequences on reef fish specialization in biogeographic transition zones

“…Total-length data were later converted into biomass (Froese et al, 2014). Information on diet and vertical position in the water column were extracted from Denis et al (2019) and completed with data available in FishBase (Froese & Pauly, 2021).…”

First record of Late Miocene Dendrophyllia de Blainville, 1830 (Scleractinia: Dendrophylliidae) in Taiwan

“…Taiwanese coral reefs and non-reefal coral communities are among the most diverse marine ecosystems on earth, hosting over a third of the world scleractinian diversity (558 species, Dai and Cheng 2020) and over 1400 reef fish species (Denis et al 2019a). The extraordinary biodiversity hosted by Taiwanese reefs, along with the coastal protection and recreational activities offered by this ecosystem, constitute a critical economic resource to the Taiwanese economy, with an average value of 514.417 US$/km 2 /year (Spalding et al 2017).…”

A Functional Perspective for Reef Benthic Communities: Temporal Trends in the Only Atoll in Southern Atlantic

“…By using species traits, functional diversity has become increasingly appropriate to evaluate and to monitor communities (Ernst et al 2006), by accessing spatiotemporal changes in different community's aspects through functional diversity indices (Mouillot et al 2013;Biggs et al 2020). On marine environments, functional approaches have been widely applied for shes and invertebrates (Bremner et al 2003(Bremner et al , 2006Halpern and Floeter 2008;Mouillot et al 2008Mouillot et al , 2014Villeger et al 2010;Bolam et al 2016;Gusmao et al 2016;Bejarano et al 2017;Richardson et al 2017;Denis et al 2019). Nevertheless, for reef benthic communities, studies assessing functional diversity are still scarce and mainly focused on corals (Darling et al 2012;Madin et al 2016;Denis et al 2017;Zawada et al 2019b;McWilliam et al 2020).…”