Isotopic life-history signatures are retained in modern and ancient Atlantic bluefin tuna vertebrae


Andrews A. J., Orton D., ONAR V., Addis P., Tinti F., Alexander M.

JOURNAL OF FISH BIOLOGY, vol.103, no.1, pp.118-129, 2023 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 103 Issue: 1
  • Publication Date: 2023
  • Doi Number: 10.1111/jfb.15417
  • Journal Name: JOURNAL OF FISH BIOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Animal Behavior Abstracts, Aquatic Science & Fisheries Abstracts (ASFA), BIOSIS, CAB Abstracts, EMBASE, MEDLINE, Veterinary Science Database
  • Page Numbers: pp.118-129
  • Keywords: fish bone turnover, historical ecology, life histories of fishes, serial sectioning, stable isotope analysis
  • Istanbul University Affiliated: No

Abstract

Isotopic, tagging and diet studies of modern-day teleosts lacked the ability to contextualise life-history and trophic dynamics with a historical perspective, when exploitation rates were lower and climatic conditions differed. Isotopic analysis of vertebrae, the most plentiful hard-part in archaeological and museum collections, can potentially fill this data-gap. Chemical signatures of habitat and diet use during growth are retained by vertebrae during bone formation. Nonetheless, to fulfil their potential to reveal life-history and trophic dynamics, we need a better understanding of the time frame recorded by vertebrae, currently lacking due to a poor understanding of fish bone remodelling. To address this issue, the authors serially-sectioned four vertebral centra of the highly migratory Atlantic bluefin tuna (Thunnus thynnus; BFT) captured off Sardinia (Italy) and analysed their isotopic composition. They show how carbon (d(13)C), nitrogen (d(15)N) and sulphur (d(34)S) isotope values can vary significantly across BFT vertebrae growth-axes, revealing patterning in dietary life histories. Further, they find that similar patterns are revealed through incremental isotopic analysis of inner and outer vertebrae centra samples from 13 archaeological BFT vertebrae dating between the 9th and13th centuries CE. The results indicate that multi-year foraging signatures are retained in vertebrae and allow for the study of life histories in both modern and paleo-environments. These novel methods can be extended across teleost taxa owing to their potential to inform management and conservation on how teleost trophic dynamics change over time and what their long-term environmental, ecological and anthropological drivers are.