Fish stable isotope community structure of a Bahamian coral reef

Abstract Stable isotopes have provided important insight into the trophic structure and interaction in many ecosystems, but to date have scarcely been applied to the complex food webs of coral reefs. We sampled white muscle tissues from the fish species composing 80% of the biomass in the 4–512 g body mass range at Cape Eleuthera (the Bahamas) in order to examine isotopic niches characterised by δ13C and δ15N data and explore whether fish body size is a driver of trophic position based on δ15N. We found the planktivore isotopic niche was distinct from those of the other trophic guilds suggesting the unique isotopic baseline of pelagic production sources. Other trophic guilds showed some level of overlap among them especially in the δ13C value which is attributable to source omnivory. Surprising features of the isotopic niches included the benthivore Halichoeres pictus, herbivores Acanthurus coeruleus and Coryphopterus personatus and omnivore Thalassoma bifasciatum being close to the planktivore guild, while the piscivore Aulostomus maculatus came within the omnivore and herbivore ellipses. These characterisations contradicted the simple trophic categories normally assigned to these species. δ15N tended to increase with body mass in most species, and at community level, the linear δ15N–log2 body mass relationship pointing to a mean predator–prey mass ratio of 1047:1 and a relatively long food chain compared with studies in other aquatic systems. This first demonstration of a positive δ15N–body mass relationship in a coral reef fish community suggested that the Cape Eleuthera coral reef food web was likely supported by one main pathway and bigger reef fishes tended to feed at higher trophic position. Such finding is similar to other marine ecosystems (e.g. North Sea).

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Coral reef degradation alters the isotopic niche of reef fishes

Marine Biology ◽

10.1007/s00227-017-3272-0 ◽

2017 ◽

Vol 164 (12) ◽

Cited By ~ 2

Author(s):

Yves Letourneur ◽

Marine J. Briand ◽

Nicholas A. J. Graham

Keyword(s):

Coral Reef ◽

Reef Fishes ◽

Isotopic Niche ◽

Reef Degradation ◽

Coral Reef Degradation

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Delineating reef fish trophic guilds with global gut content data synthesis and phylogeny

PLoS Biology ◽

10.1371/journal.pbio.3000702 ◽

2020 ◽

Vol 18 (12) ◽

pp. e3000702

Author(s):

Valeriano Parravicini ◽

Jordan M. Casey ◽

Nina M. D. Schiettekatte ◽

Simon J. Brandl ◽

Chloé Pozas-Schacre ◽

...

Keyword(s):

Machine Learning ◽

Coral Reef ◽

Reef Fish ◽

Trophic Interactions ◽

Reef Fishes ◽

Trophic Niche ◽

Coral Reef Fishes ◽

Misclassification Error ◽

Trophic Guilds ◽

Gut Content

Understanding species’ roles in food webs requires an accurate assessment of their trophic niche. However, it is challenging to delineate potential trophic interactions across an ecosystem, and a paucity of empirical information often leads to inconsistent definitions of trophic guilds based on expert opinion, especially when applied to hyperdiverse ecosystems. Using coral reef fishes as a model group, we show that experts disagree on the assignment of broad trophic guilds for more than 20% of species, which hampers comparability across studies. Here, we propose a quantitative, unbiased, and reproducible approach to define trophic guilds and apply recent advances in machine learning to predict probabilities of pairwise trophic interactions with high accuracy. We synthesize data from community-wide gut content analyses of tropical coral reef fishes worldwide, resulting in diet information from 13,961 individuals belonging to 615 reef fish. We then use network analysis to identify 8 trophic guilds and Bayesian phylogenetic modeling to show that trophic guilds can be predicted based on phylogeny and maximum body size. Finally, we use machine learning to test whether pairwise trophic interactions can be predicted with accuracy. Our models achieved a misclassification error of less than 5%, indicating that our approach results in a quantitative and reproducible trophic categorization scheme, as well as high-resolution probabilities of trophic interactions. By applying our framework to the most diverse vertebrate consumer group, we show that it can be applied to other organismal groups to advance reproducibility in trait-based ecology. Our work thus provides a viable approach to account for the complexity of predator–prey interactions in highly diverse ecosystems.

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Global gut content data synthesis and phylogeny delineate reef fish trophic guilds

10.1101/2020.03.04.977116 ◽

2020 ◽

Author(s):

Valeriano Parravicini ◽

Jordan M. Casey ◽

Nina M. D. Schiettekatte ◽

Simon J. Brandl ◽

Chloé Pozas-Schacre ◽

...

Keyword(s):

Coral Reef ◽

Reef Fish ◽

Ecosystem Functioning ◽

Reef Fishes ◽

Coral Reef Fishes ◽

Misclassification Error ◽

Biological Traits ◽

Trophic Guilds ◽

Gut Content ◽

Viable Approach

AbstractThe diversity of life on our planet has produced a remarkable variety of biological traits that characterize different species. Such traits are widely employed instead of taxonomy to increase our understanding of biodiversity and ecosystem functioning. However, for species’ trophic niches, one of the most critical aspects of organismal ecology, a paucity of empirical information has led to inconsistent definitions of trophic guilds based on expert opinion. Using coral reef fishes as a model, we show that experts often disagree on the assignment of trophic guilds for the same species. Even when broad categories are assigned, 60% of the evaluated trait schemes disagree on the attribution of trophic categories for at least 20% of the species. This disagreement greatly hampers comparability across studies. Here, we introduce a quantitative, unbiased, and fully reproducible framework to define species’ trophic guilds based on empirical data. First, we synthesize data from community-wide visual gut content analysis of tropical coral reef fishes, resulting in trophic information from 13,961 individuals belonging to 615 reef fish species across all ocean basins. We then use network analysis to cluster the resulting global bipartite food web into distinct trophic guilds, resulting in eight trophic guilds, and employ a Bayesian phylogenetic model to predict trophic guilds based on phylogeny and maximum body size. Our model achieved a misclassification error of 5%, indicating that our approach results in a quantitative and reproducible trophic categorization scheme, which can be updated as new information becomes available. Although our case study is for reef fishes, the most diverse vertebrate consumer group, our approach can be applied to other organismal groups to advance reproducibility in trait-based ecology. As such, our work provides an empirical and conceptual advancement for trait-based ecology and a viable approach to monitor ecosystem functioning in our changing world.

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Identifying carbon sources and trophic position of coral reef fishes using diet and stable isotope (δ15N and δ13C) analyses in two contrasted bays in Moorea, French Polynesia

Coral Reefs ◽

10.1007/s00338-013-1073-6 ◽

2013 ◽

Vol 32 (4) ◽

pp. 1091-1102 ◽

Cited By ~ 19

Author(s):

Y. Letourneur ◽

T. Lison de Loma ◽

P. Richard ◽

M. L. Harmelin-Vivien ◽

P. Cresson ◽

...

Keyword(s):

Coral Reef ◽

Stable Isotope ◽

Trophic Position ◽

Carbon Sources ◽

Reef Fishes ◽

French Polynesia ◽

Coral Reef Fishes ◽

Δ15n And Δ13c

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Faculty Opinions recommendation of The historical biogeography of coral reef fishes: global patterns of origination and dispersal.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717963671.793465555 ◽

2012 ◽

Author(s):

Ferdinando Boero ◽

Valeriano Parravicini

Keyword(s):

Coral Reef ◽

Reef Fishes ◽

Coral Reef Fishes ◽

Historical Biogeography ◽

Global Patterns

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The isotopic niche of Atlantic, biting marine mammals and its relationship to skull morphology and body size

Scientific Reports ◽

10.1038/s41598-021-94610-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Massimiliano Drago ◽

Marco Signaroli ◽

Meica Valdivia ◽

Enrique M. González ◽

Asunción Borrell ◽

...

Keyword(s):

Body Size ◽

Atlantic Ocean ◽

Fisheries Management ◽

Marine Mammals ◽

Trophic Position ◽

Sympatric Species ◽

Isotopic Niche ◽

Apex Predators ◽

Skull Morphology ◽

Ecosystem Based Fisheries Management

AbstractUnderstanding the trophic niches of marine apex predators is necessary to understand interactions between species and to achieve sustainable, ecosystem-based fisheries management. Here, we review the stable carbon and nitrogen isotope ratios for biting marine mammals inhabiting the Atlantic Ocean to test the hypothesis that the relative position of each species within the isospace is rather invariant and that common and predictable patterns of resource partitioning exists because of constrains imposed by body size and skull morphology. Furthermore, we analyze in detail two species-rich communities to test the hypotheses that marine mammals are gape limited and that trophic position increases with gape size. The isotopic niches of species were highly consistent across regions and the topology of the community within the isospace was well conserved across the Atlantic Ocean. Furthermore, pinnipeds exhibited a much lower diversity of isotopic niches than odontocetes. Results also revealed body size as a poor predictor of the isotopic niche, a modest role of skull morphology in determining it, no evidence of gape limitation and little overlap in the isotopic niche of sympatric species. The overall evidence suggests limited trophic flexibility for most species and low ecological redundancy, which should be considered for ecosystem-based fisheries management.

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