Marine Biology

, Volume 156, Issue 2, pp 127–139

Do ovarian scars persist with age in all Cetaceans: new insight from the short-beaked common dolphin (Delphinus delphis Linnaeus, 1758)

Authors

  • Willy Dabin
    • Centre de Recherche sur les Mammifères MarinsUniversité de La Rochelle
  • François Cossais
    • Centre de Recherche sur les Mammifères MarinsUniversité de La Rochelle
  • Graham J. Pierce
    • Centro Oceanográfico de VigoInstituto Español de Oceanografía
    • Oceanlab, University of Aberdeen
    • Centre de Recherche sur les Mammifères MarinsUniversité de La Rochelle
    • LIttoral ENvironnement et SociétésUMR 6250, CNRS-Université de La Rochelle
Original Paper

DOI: 10.1007/s00227-008-1070-4

Cite this article as:
Dabin, W., Cossais, F., Pierce, G.J. et al. Mar Biol (2008) 156: 127. doi:10.1007/s00227-008-1070-4

Abstract

The determination of reproductive status and the reconstruction of individual reproductive histories are central to many ecological studies. In cetaceans, it has been assumed that ovarian scars accumulate with age and provide a lifetime record of female reproductive history. If ovarian scars persist, the number of scars should increase with age after puberty. To test this, we examined age, reproductive status and ovarian scars from 187 short-beaked common dolphins (Delphinus delphis) from the eastern North Atlantic. The number of Corpus Albicans (CA) present in ovaries did not increase with age after age at sexual maturity (ASM), suggesting that ovarian scars are not persistent and that their number at any one time would be a function of rates of ovulation and healing, the latter being defined here as the resorption or disintegration of CA tissue. Since female mammals stop ovulating when pregnant, inferences about healing rates could be made by using pregnant females. Pregnant females had ca. 40% fewer scars than non-pregnant females. This suggests that most CAs would heal quickly, with a half-life of less than 1 year, although larger scars may persist longer. Therefore, counting CAs would have limited potential for reconstructing individual reproductive lifetime histories in the common dolphin. A reassessment of the use of ovarian scars to reconstruct individual life reproductive histories in cetaceans is suggested.

Copyright information

© Springer-Verlag 2008