Marsh, Lachlan M.

1 publication

Marsh, Helene D.; Heinsohn, George Edwin; Marsh, Lachlan M. (detail)
1984Breeding cycle, life history and population dynamics of the dugong, Dugong dugon (Sirenia: Dugongidae).
Austral. Jour. Zool. 32(6): 767-788. 5 tabs. 3 figs.
—Reports that fertility is discontinuous in both males and females; calving is diffusely seasonal; neonates are 1.0-1.3 m long; sexual maturity is attained at 2.2-2.5 m and at least 9-10 years; gestation lasts about 1 year and lactation at least 1.5 years; the sex ratio is 1:1; the calving interval is 3-7 years; mortality is more important than the age of maturity in influencing population dynamics; estrus can occur during lactation; the low nutritive value of seagrasses may explain the discontinuous fertility; and the delay in maturity may be density-dependent. Gives original accounts of three births, one shark attack, and one case of males fighting with their tusks.