MEPS 502:281-294 (2014)  -  DOI: https://doi.org/10.3354/meps10709

ABSTRACT: A total of 79 (37 juvenile male, 42 adult female) southern elephant seals Mirounga leonina from the Kerguelen Islands were tracked between 2004 and 2009. Area-restricted search patterns and dive behaviour were established from location data gathered by CTD satellite-relayed data loggers. At-sea movements of the seals demonstrated that >40% of the juvenile elephant seal population tagged use the Kerguelen Plateau during the austral winter. Search activity increased where temperature at 200 m depth was lower, when closer to the shelf break, and, to a lesser extent, where sea-surface height anomalies were higher. However, while this model explained the observed data (F_1,242 = 88.23, p < 0.0001), bootstrap analysis revealed poor predictive capacity (r² = 0.264). There appears to be potential overlap between the seals and commercial fishing operations in the region. This study may therefore support ecosystem-based fisheries management of the region, with the aim of maintaining ecological integrity of the shelf.

KEY WORDS: Diving behaviour · 3-dimensional utilisation · Shelf break · Temperature · Sea‑surface height · Fisheries management