Fatty Acid Biomarkers Reveal Maternal Energy Allocation Strategies in Spawning Snapper (Chrysophrys auratus)

Abstract

Investigating the dynamic interplay between energy storage and provisioning offers valuable insights into reproductive strategies. In this study we utilised fatty acids as proxy biomarkers to investigate the energetic provisioning strategy of spawning Snapper (Chrysophrys auratus). Fatty acid profiles of liver, ovaries, and skeletal muscle showed significant variations in composition and concentration. The liver was rich in saturated fatty acids (ΣSFA, 68.52%), the ovaries were predominantly composed of polyunsaturated fatty acids (ΣPUFA, 43.44%), and skeletal muscle exhibited near equal proportions of ΣSFA (42.52%) and ΣPUFA (40.46%). This pattern indicates a mixed reproductive strategy, where high accumulation of SFA in the liver supports capital breeding traits, while higher PUFA levels in the ovaries, and equal SFA and PUFA composition in muscle tissue indicate characteristics associated with income breeding. We also found no convincing evidence to support the lipid provisioning aspect of the Big Old Fat Fecund Female Fish (BOFFFF) hypothesis, as older snapper did not provision higher concentrations of fatty acids in their ovaries. These findings provide new insights into resource allocation strategies of snapper during reproduction, suggesting that protecting a range of age classes, rather than focusing solely on older individuals, may be more effective for managing and ensuring stock sustainability.