Winter distribution and group composition of humpback whales (Megaptera novaeangliae) off northern Peru

• Published in: Latin American Journal of Aquatic Mammals
• Main Authors: Pacheco, A. S., Silva, S., Alcorta, B.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Sociedad Latinoamericana de Especialistas en Mamíferos Acuáticos (SOLAMAC) 2009
• Subjects: Pacific; Megaptera novaeangliae
• Online Access: http://lajamjournal.org/index.php/lajam/article/view/285; https://doi.org/10.5597/lajam00131

From late July to the end of September 2009, the temporal and spatial distribution and group composition of humpback whales (Megaptera novaeangliae) were studied in order to provide new information about the species in northern Peru, the southern limit of the breeding area for the Southeast Pacific population. Daily surveys were made from a whale-watching boat from Los Organos (04°10'38.78"S, 81°8'04.40"W) and covering an area of approximately 74km2. Data about geographic position and group composition are presented. A total of 43 trips yielded a total of 124 sightings. Whales were observed throughout the study period with a peak in abundance in late August. Humpbacks were distributed mainly in shallow waters between 20 and 50m depth. Pairs and trios were the most common group type, whereas adults and mother/calf pairs were the principal sex/age classes. Our data confirms breeding and nursing activities in the southern limit of the wintering area for the Southeast Pacific stock. Frequent use of the shallow waters of the northern Peruvian coast by fishing operations may cause negative impacts on this sensitive phase in the humpback's life cycle. Thus, strengthening the current protection measures is encouraged.