Jenny Christal

My PhD was entitled "An analysis of sperm whale social structure: patterns of association and genetic relatedness". My field research was based in the Galápagos Islands breeding ground (on the equator, 1000km west of Ecuador, South America). Dr Hal Whitehead began a photo-identification study of this sperm whale population in 1985. Up to and including my field season in 1997, we now have records spanning 12 years.

I used photo-identification and behavioural data to examine patterns of association, and hence, relationships between individual sperm whales. Genetic techniques using Mitochondrial d-loop and microsatellite markers, and DNA extracted from sloughed skin samples, enabled me to compare association patterns to patterns of genetic relatedness.

Thesis Table of Contents:

  • Chapter One: Introduction
  • Chapter Two: Temporal analysis of the social structure of female and juvenile sperm whales
  • Chapter Three: Sperm whale social units: variation and change
  • Chapter Four: The genetic structure of sperm whale social units and groups
  • Chapter Five: Patterns of association within sperm whale groups: reflections of long-term relationships and genetic relatedness?
  • Chapter Six: The abundance and behaviour of large male sperm whales around the Galapagos Islands
  • Chapter Seven: General discussion
  • Appendix One: Details of delineated units

    Christal, J., and H. Whitehead. 2001. Social affiliations within sperm whale (Physeter macrocephalus) groups. Ethology 107: 323-340.
    Christal, J., H. Whitehead and E. Lettevall. 1998. Sperm whale social units: variation and change. Can. J. Zool. 76: 1431-1440
    Whitehead, H., J. Christal, and S. Dufault. 1997. Past and distant whaling and the rapid decline of sperm whales off the Galápagos Islands. Conservation Biology 11: 1387-1396
    Christal J., and H. Whitehead. 1997. Aggregations of mature male sperm whales on the Galápagos Islands breeding ground. Marine Mammal Science 13:59-69

    Return to Dalhousie Whale Research Last Updated December, 1998 by Jenny Christal