A small (~1.5 m) adult male scalloped hammerhead, Sphyrna lewini

The life histories of endangered hammerhead sharks (Carcharhiniformes, Sphyrnidae) from the east coast of Australia

Journal of Fish Biology

This paper was the fourth chapter of my PhD and investigated the life history of scalloped hammerhead, Sphyrna lewini, and great hammerhead, Sphyrna mokarran. Highlights of this paper included the rather surprising success of the age validation study on S. mokarran, which ended up being recaptured in high numbers by commercial fishers. Adrian Gutteridge contributed a calcein marked individual at liberty for over two years that had spectacularly clear vertebrae.

Other interesting aspects of this paper included the occurrence of “pelagic” and “coastal” strategist males, as I termed them. The ratio of male to female length at maturity tends to be invariant. Why some male S. lewini in Australian waters mature at such a small size relative to females is rather interesting.