Sex identification of humpback whales, Megaptera novaeangliae , on the wintering grounds of the Mexican Pacific Ocean

• Published in: Canadian Journal of Zoology
• Main Authors: Medrano, L., Salinas, M., Salas, I., Guevara, P. Ladrón de, Aguayo, A., Jacobsen, J., Baker, C. S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1994
• Subjects: Animal Science and Zoology; Ecology, Evolution, Behavior and Systematics; Megaptera novaeangliae
• Online Access: http://dx.doi.org/10.1139/z94-239; http://www.nrcresearchpress.com/doi/pdf/10.1139/z94-239

The sex of 43 humpback whales (Megaptera novaeangliae) from different social groupings in the Mexican Pacific was identified by a molecular analysis of skin biopsy samples. Of the 18 whales sampled from surface-active groups, 17 were males. Three singers were sampled and identified as males. In two cases, whales interrupting and joining a singer without exhibiting agonistic behavior were identified as females. A higher proportion of males was found in the samples collected at the Revillagigedo Islands, reflecting a greater sampling effort on surface-active groups. Preliminary data showed that along the Mexican Pacific coast, the migratory arrival of males corresponds closely to the timing of competitive activity.