Current address: Greenland Institute of Natural Resources, % Danish Polar Centre, Strandgade 100H, DK-1401 Copenhagen, Denmark; e-mail: email@example.com.
REPRODUCTION IN MALE ATLANTIC WALRUSES (ODOBENUS ROSMARUS ROSMARUS) FROM THE NORTH WATER (N BAFFIN BAY)
Article first published online: 26 AUG 2006
Marine Mammal Science
Volume 19, Issue 4, pages 819–831, October 2003
How to Cite
Born, E. W. (2003), REPRODUCTION IN MALE ATLANTIC WALRUSES (ODOBENUS ROSMARUS ROSMARUS) FROM THE NORTH WATER (N BAFFIN BAY). Marine Mammal Science, 19: 819–831. doi: 10.1111/j.1748-7692.2003.tb01132.x
- Issue published online: 26 AUG 2006
- Article first published online: 26 AUG 2006
- Received: 3 October 2002 Accepted: 21 March 2003
- Atlantic walrus;
- Odobenus rosmarus rosmarus;
- North Water;
- male reproduction
Age at sexual maturity and timing of the mating season were determined in male Atlantic walruses (Odobenus rosmarus rosmarus, L.) from the “North Water” subpopulation in northern Baffin Bay. Testes and epididymides of 174 male walruses (between 0 and 30 yr old) from NW Greenland (1987–1990) were studied macroscopically and a subset of 57 specimens was analyzed microscopically. In physically mature bulls (i.e., ≥12 yr old), sperm or apparently ripe spermatids were found between 9 November and 12 July. In younger walruses these signs of fertility were found in a few specimens (7–11 yr old) collected between 9 January and 28 May. The mating season seems to peak in January—April. The youngest sexually mature individual was 7 yr old and the oldest apparently immature individual was 13 yr old. Average age of sexual maturity was 10.9 yr (95% C.I.: 9–6–12.2 yr) and all were sexually mature by the time they were 14 yr old. The non-spermiogenetic testes and epididymides showed accelerated growth between about the 5–6th and about the 12–15th year of life, indicating that sexual maturation occurs during these years. The length of the baculum increased gradually until about 12–15 yr of age, when physical maturity was reached.