Predation on cephalopods by Weddell seals, Leptonychotes weddellii, at Hope Bay, Antarctic Peninsula

• Published in: Polar biology Vol. 35; no. 4; pp. 585 - 592
• Main Authors: Daneri, G. A., Carlini, A. R., Negri, A., Allcock, A. L., Corbalán, A.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01-04-2012; Springer; Springer Nature B.V
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Aquatic birds; Aquatic mammals; Autoecology; Biological and medical sciences; Biomedical and Life Sciences; Ecology; Food resources; Fundamental and applied biological sciences. Psychology; General aspects; Invertebrates; Leptonychotes weddellii; Life Sciences; Marine; Marine ecology; Marine environment; Marine mammals; Microbiology; Mollusca; Mollusks; Oceanography; Original Paper; Pareledone; Pareledone turqueti; Particular ecosystems; Plant Sciences; Predation; Predators; Prey; Seals; Synecology; Trophic relationships; Zoology; PSW, Antarctica, Antarctic Peninsula; PSW, Antarctica, Antarctic Peninsula, Graham Land, Hope Bay; Diet; Antarctic Peninsula; Cephalopods; Weddell seals; Carnivora; Leptonychotes weddellii; Cephalopoda; Vertebrata; Mammalia; Polar region; Bay; Predation; Leptonychotes; Invertebrata; Mollusca
• ISSN: 0722-4060; 1432-2056
• DOI: 10.1007/s00300-011-1104-0

Cephalopods play a key role in marine environments as food resources for top predators such as marine mammals and seabirds. However, detailed information on their trophic relationships with Antarctic seals is scarce. The aim of the present study was to examine the cephalopod portion of the diet of adult and subadult Weddell seals,
Leptonychotes weddellii
, at Hope Bay, Antarctic Peninsula, through the analysis of scats collected during three consecutive summers (2003, 2004 and 2005). Cephalopods occurred in almost 45% of the 217 samples collected during the whole period of study. A total of 662 beaks (358 upper and 304 lower) were removed from scats containing cephalopod remains (
n
 = 93). Octopods were largely dominant in comparison with teuthoids constituting in numerical abundance over 95% of the cephalopod prey. The octopod
Pareledone turqueti
was the most frequent and dominant prey species representing, respectively, 57.9 and 71.1% in numbers and biomass of cephalopods consumed. Species belonging to the group of papillated
Pareledone
were second in importance. The results were compared with information from previous dietary studies of
L. weddellii
at other localities of Antarctica. Based on the examination of the cephalopod prey taxa identified in this study, it is suggested that during the study period Weddell seal individuals foraged mainly on benthic prey resources close to the coast, in inshore waters where octopods were dominant in comparison with pelagic squid.