Environmental Biology of Fishes

, Volume 18, Issue 1, pp 27–40

The determinants of sexual segregation in the scalloped hammerhead shark,Sphyrna lewini

Authors

  • A. Pete Klimley
    • Marine Biology Research Division (A-002), Scripps Institution of OceanographyUniversity of California
Article

DOI: 10.1007/BF00002325

Cite this article as:
Klimley, A.P. Environ Biol Fish (1987) 18: 27. doi:10.1007/BF00002325

Synopsis

Female scalloped hammerhead sharks move offshore at a smaller size than do males to form schools composed primarily of intermediate size female sharks. This movement results in smaller females feeding more on pelagic prey than do males and with greater predatory success. It is contended that this change in habitat causes females to grow more rapidly to reproductive size. Intermediate size females grow at a more rapid rate than males. Female scalloped hammerhead sharks mature at a size larger than males. For many elasmobranch species, females: (1) occupy a different habitat, (2) grow more rapidly prior to maturity and continue growth following maturation, (3) feed on different prey with increased feeding success, and (4) reproduce at a size larger than males. It is suggested that female segregation increases fitness, resulting in more rapid growth for the former sex. The females reach maturity at the larger size necessary to support embryonic young, yet similar age to males, matching the female reproductive lifetime to that of males.

Keywords

Diet Growth Bimaturism Elasmobranch Reproductive size

Copyright information

© Dr W. Junk Publishers 1987