Premium
Seasonal occurrence of southeast Pacific blue whale songs in southern Chile and the eastern tropical Pacific
Author(s) -
Buchan Susannah J.,
Stafford Kathleen M.,
HuckeGaete Rodrigo
Publication year - 2015
Publication title -
marine mammal science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.723
H-Index - 78
eISSN - 1748-7692
pISSN - 0824-0469
DOI - 10.1111/mms.12173
Subject(s) - geography , endangered species , ecoregion , pacific ocean , tropical eastern pacific , oceanography , climatology , environmental science , ecology , biology , geology , habitat
Passive acoustic data were collected January 2012 to April 2013 at four sites in the Chiloense Ecoregion ( CER ) in southern Chile (≈43°S–44°S, 71°W–73°W) and 1996–2002 from one site in the eastern tropical Pacific ( ETP ) (8°S, 95°W). Automatic detectors were used to detect the two songs ( SEP 1 and SEP 2) described for southeast Pacific ( SEP ) blue whales. There was a strong seasonal pattern of occurrence of SEP songs in the CER from December to August, peaking March to May. In the ETP , the occurrence of songs was an order of magnitude lower but songs were present year‐round, with a peak around June. These findings support austral summer/autumn seasonal residency in the CER and a seasonal movement of blue whales towards the ETP during June/July, returning in December. Interannual differences in the ETP were possibly linked to the 1997–1998 El Niño event. At both study sites, SEP 2 was significantly more common than SEP 1; both songs largely followed the same temporal trends. These findings contribute to our understanding of the seasonal movements of endangered SEP blue whales and can inform conservation strategies, particularly in the CER coastal feeding ground. We recommend future year‐round passive acoustic studies in the CER and the ETP ( e.g ., near the Galapagos Islands), ideally coupled with oceanographic data.