Skip to content

Research at St Andrews

Changes in stable isotope compositions during fasting in phocid seals

Research output: Contribution to journalArticle


Open Access permissions



Sarah Habran, France Damseaux, Patrick Pomeroy, Cathy Debier, Daniel Crocker, Gilles Lepoint, Krishna Das

School/Research organisations


Rationale:  The grey seal, Halichoerus grypus (GS), and the northern elephant seal, Mirounga angustirostris (NES), come ashore for reproduction. This period involves intense physiological processes such as lactation in females and a developmental post‐weaning fast in juveniles. Previous studies have shown that δ13C and δ15N values are affected by starvation, but the precise effects of fasting associated to lactation and post‐weaning fast in seals remain poorly understood.

Methods:  To examine the effect of lactation and post‐weaning fast on stable isotope ratios in GS and NES, blood and hair were sampled from twenty‐one GS mother‐pup pairs on the Isle of May and on twenty‐two weaned NES pups at Año Nuevo State Reserve during their respective breeding seasons. Milk samples were also collected from GS mothers. Stable isotope measurements were performed with an isotope ratio mass spectrometer coupled to an N‐C elemental analyser.
Results:  Changes in stable isotope ratios in blood components during fasting were similar and weak between GS and NES mothers especially in blood cells (GS: Δ15N = 0.05‰, Δ13C = 0.02‰; NES: Δ15N = 0.1‰, Δ13C = 0.1‰). GS showed a 15N discrimination factor between maternal and pup blood cells and milk, but not for 13C. The strongest relationship between the isotopic compositions of the mother and the pup was observed in the blood cells.
Conclusion:  Isotopic consequences of lactation, fasting, and growth seem limited in NES and GS, especially in medium‐term integrator tissues of feeding activity such as blood cells. Stable isotope ratios in the blood of pups and mothers are correlated. We observed a subtle mother‐to‐pup fractionation factor. Our results suggest that pup blood cells are mostly relevant for exploring the ecology of female seals.


Original languageEnglish
Pages (from-to)176-184
Number of pages9
JournalRapid Communications in Mass Spectrometry
Issue number2
Early online date19 Dec 2018
Publication statusPublished - 30 Jan 2019

    Research areas

  • Stable isotopes, Seal, Lactation, Post-weaning fast, Reproduction

Discover related content
Find related publications, people, projects and more using interactive charts.

View graph of relations

Related by author

  1. Environment-sensitive mass changes influence breeding in a capital breeding marine top predator

    Smout, S. C., King, R. & Pomeroy, P., 20 Nov 2019, In : Journal of Animal Ecology. Early View, 13 p.

    Research output: Contribution to journalArticle

  2. EIRPHOT : A critical assessment of Wales’ grey seal ( Halichoerus grypus ) photo - identification database .

    Langley, I. J., Rosas Da Costa Oliver, T. V., Stringell, T., Morris, C., Hiby, L. & Pomeroy, P., 21 Jan 2019, Bangor: Natural Resources Wales. 94 p. (evidence report series; no. 280)

    Research output: Book/ReportCommissioned report

Related by journal

  1. Triple oxygen isotope analysis of nitrate using isotope exchange - cavity ringdown laser spectroscopy

    Gázquez, F. & Claire, M. W., 30 Nov 2018, In : Rapid Communications in Mass Spectrometry. 32, 22, p. 1949-1961

    Research output: Contribution to journalArticle

  2. Matrix-free mass spectrometric imaging using laser desorption ionisation Fourier transform ion cyclotron resonance mass spectrometry

    Goodwin, R. J. A., Pitt, A. R., Harrison, D., Weidt, S. K., Langridge-Smith, P. R. R., Barrett, M. P. & Logan Mackay, C., 2011, In : Rapid Communications in Mass Spectrometry. 25, 7, p. 969-972 4 p.

    Research output: Contribution to journalArticle

  3. Recovery of organic matter from mineral-rich sediment and soils for stable isotope analyses using static dense media

    Wurster, C. M., Saiz, G., Calder, A. & Bird, M. I., 15 Jan 2010, In : Rapid Communications in Mass Spectrometry. 24, 1, p. 165-168 4 p.

    Research output: Contribution to journalArticle

Related by journal

  1. Rapid Communications in Mass Spectrometry (Journal)

    Nora Nell Hanson (Reviewer)
    Dec 2011

    Activity: Publication peer-review and editorial work typesPeer review of manuscripts

ID: 255222209