Consumers mediate nutrient cycling through excretion and egestion across most ecosystems. In nutrient‐poor tropical waters such as coral reefs, nutrient cycling is critical for maintaining productivity. While the cycling of fish‐derived inorganic nutrients via excretion has been extensively investigated, the role of egestion for nutrient cycling has remained poorly explored. We sampled the fecal contents of 570 individual fishes across 40 species, representing six dominant trophic guilds of coral reef fishes in Moorea, French Polynesia. We measured fecal macro‐ (proteins, carbohydrates, lipids) and micro‐ (calcium, copper, iron, magnesium, manganese, zinc) nutrients and compared the fecal nutrient quantity and quality across trophic guilds, taxa, and body size. Macro‐ and micronutrient concentrations in fish feces varied markedly across species. Genera and trophic guild best predicted fecal nutrient concentrations. In addition, nutrient composition in feces was unique among species within both trophic guilds (herbivores and corallivores) and genera (
This content will become publicly available on September 11, 2024
- Award ID(s):
- 1829380
- NSF-PAR ID:
- 10472539
- Editor(s):
- R. Causse
- Publisher / Repository:
- Société Française d'Ichtyologie
- Date Published:
- Journal Name:
- Cybium
- ISSN:
- 0399-0974
- Subject(s) / Keyword(s):
- ["Coral reef fishes","French Polynesia","Length-weight relationships","Morphology","Aquarium species","Biomass"]
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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