Prey of the Antarctic fur seal Arctocephalus gazella at Marion Island
Loading...
Date
Authors
Makhado, Azwianewi Benedict
Bester, Marthan Nieuwoudt
Kirkman, Steve P. (Stephen Patrick)
Pistorius, Pierre Anton
Ferguson, Jan Willem Helenus
Klages, N.T.W.
Journal Title
Journal ISSN
Volume Title
Publisher
Springer
Abstract
The prey of Antarctic fur seals, Arctocephalus gazella, was investigated through scat analysis at Marion Island from 1996 until 2000. A total of 25 different prey species were identified from scats, of which 21 were fish, 1 crustacean and 3 cephalopods. Fish were by far the main prey item, occurring in 96.1% of samples, followed by crustaceans (2.7%) and cephalopods (1.2%). Fishes from the family Myctophidae (Gymnoscopelus piabilis, Electrona carlsbergi, G. fraseri and E. subaspera) were the most abundant prey (97.2%) every year, while those from the families Notothenididae, Paralepididae, Notosudidae, Microstomatidae and Gempylidae were present in small numbers. G. piabilis, E. carlsbergi, E. subaspera and G. nicholsi contributed the most in terms of biomass to the diet. Significant seasonal differences existed in the diet when comparing summer and winter. G. piabilis, K. anderssoni, P. bolini and P. choriodon dominated in summer as opposed to E. carlsbergi, E. subaspera, G. fraseri and G. nicholsi that dominated in winter. The fish varied in size and mass, from the small K. anderssoni to the large Paranotothenia magellanica. Cephalopods and the crustacean Nauticaris marionis, in very low numbers and in winter, appeared in the scats, but not in all years of study. Unidentified penguin remains rarely turned up in scats.
Description
Keywords
Arctocephalus gazella, Otoliths, Prey species, Frequency of occurrence, Numerical abundance
Sustainable Development Goals
Citation
Makhado, AB, Bester, MN, Kirkman, SP, Pistorius, PA, Ferguson, JWH & Klages, NTW 2008, ‘Prey of the Antarctic fur seal Arctocephalus gezella at Marion Island’, Polar Biology, vol. 31, no. 5, pp. 575-581. [http://www.springer.com/life+sci/ecology/journal/300]