Population and growth parameters of Galapagos sperm whales estimated from length distributions

Length distributions of female and immature Physeter macrocephalus showed most animals to be 8.6-10.2 m. A simple population model estimated population and growth parameters for female and immature sperm whales off the Galapagos by comparing the Galapagos length distribution with that expected given certain population and growth parameters. Galapagos data were most consistent with a significantly reduced pregnancy rate (2-4% of mature females per year) and smaller lengths of females at physical maturity (10.2m), and suggested a low mean mortality of mature females if the population is near equilibrium. -from Authors