Abstract

Occurrence of fin and humpback whales in the Scotia Sea and the protected marine area of the South Orkney Islands, Antarctica. Mastozool. neotrop. [online]. 2017, vol.24, n.1, pp.135-143. ISSN 0327-9383.

The water masses around the South Orkney Islands (SOI) and their Protected Marine Area (PMA) in the Scotia Sea, Antarctica, are among the biologically richest areas of the Southern Ocean, supporting a large community of top predators. Information about the occurrence of whales in the southern Scotia Sea is scarce, partly due to the difficulty of conducting research in Antarctic waters. The aims of this paper are to report new observations of fin and humpback whales in the southern Scotia Sea and SOI PMA, and to describe envi­ronmental conditions associated with their occurrence. The study was conducted onboard R/V Puerto Deseado between 58ºS and 64ºS latitude, covering a total of 588 nm from 15 February to 15 March 2014. A principal component analysis was used to identify patterns of occurrence. Fin whales were associated with higher values of sea surface temperature (SST), salinity and depth. The largest aggregations of fin whales were located NW of the SOI. By contrast, humpback whales occurred in shallower areas with lower SST and salinity, and the largest aggregations were south of 60ºS, in or near the PMA. Our analyses are based on a single 25-day cruise but provide new information on the summer occurrence of fin and humpback whales in the southern Scotia Sea and SOI PMA, an area rarely visited by research vessels devoted to studies of top predators.

Keywords : Antarctica; Distribution; Fin whales; Humpback whales.