Reproduction
Lucena (2006) suggested that Antarctic minke whales are polygamous, judging by the structure of groups in breeding grounds. Little is known about mating behavior in any rorqual.
Mating System: polygynandrous (promiscuous)
Kasamatsu et al. (1995) found that minke whales (probably Balaenoptera bonaerensis) migrate far north but their main breeding areas are probably between 10º and 20º S. Breeding populations may be relatively dispersed and do not seem to be associated with the coast. The generation time is estimated to be about 22 years.
Antarctic minke whales, like common minke whales, have a gestation period of 10 months, after which a single young is born at about 2.7 meters long. Calves stay with their mother for up to 2 years and may nurse for 3 to 6 months.
In Antarctic minke whales, the age at which sexual maturity is reached has been shown to have decreased from an average of age 11 in the cohorts of 1950’s to about 7 years old in the 1970’s cohorts.
Breeding interval: Antarctic minke whale females can breed up to every year, although it is more common for them to breed less often.
Breeding season: It is thought that the breeding season occurs during the austral summer.
Average number of offspring: 1.
Average gestation period: 10 months.
Range weaning age: 3 to 6 months.
Range time to independence: 2 (high) years.
Average age at sexual or reproductive maturity (female): 7 years.
Average age at sexual or reproductive maturity (male): 7 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); viviparous
Female Antarctic minke whales gestate, nurse, and protect their young for up to two years. Males do not provide parental care. The milk of their close relatives, common minke whales (Balaenoptera acutorostrata), contains lactose and several other oligosaccharides, some of which have never been found in any other mammalian species. These new oligosaccharides may have a function in the immunity of the neonate.
Parental Investment: precocial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female); pre-independence (Protecting: Female)
- Kasamatsu, F., S. Nishiwaki, H. Ishikawa. 1995. Breeding areas and southbound migrations of southern minke whales Balaenoptera acurostrata. Marine Ecology Progress Series, 119: 1-10.
- Lucena, A. 2006. Minke whale Balaenoptera bonaerensis (Burmeister)(Cetacea, Balaenopteridae) population structure in the breeding grounds off South Atlantic Ocean. Revista Brasileira de Zoologia, 23(1): 176-185.
- Thomson, R., D. Butterworth, H. Kato. 1999. Has the age at transition of Southern Hemisphere minke whales declined over recent decades?. Marine Mammal Science, 15(3): 661-682.
- Urashima, T., H. Sato, J. Munakata, T. Nakamura, I. Arai, T. Saito, M. Tetsuka, Y. Fukui, H. Ishikawa, C. Lydersen, K. Kovacs. 2002. Chemical characterization of the oligosaccharides in beluga (Delphinapterus leucas) and Minke whale (Balaenoptera acutorostrata) milk. Comparative Biochemistry and Physiology B-Biochemistry and Molecular Biology, 132(3): 611-624.
- Schueller, G. 2004. Rorquals (Balaenopteridae). Pp. 119-130 in M Hutchins, A Evans, J Jackson, D Kleiman, J Murphy, D Thoney, eds. Grzimek's Animal Life Encyclopedia, Vol. Vol. 15: Mammals IV., 2nd ed Edition. Detroit: The Gale Group.
