Chris Fallows observed and photographed Cape fur seals (Arctocephalus pusillus) attacking and partially consuming free swimming mid-sized blue sharks off Cape Point, South Africa. One seal was even seen to attack five sharks in succession within two hours. The seals were mainly interested in the nutritious parts like stomach content and liver of the sharks. See also the recent article by Chris a.o.
http://dx.doi.org/10.2989/1814232X.2015.1013058
The behavior of these fur seals reminds me of grey seals (Halichoerus grypus) that are now hold responsible for attacking and consuming porpoises in the coastal waters of the Netherlands. Jeremy Stafford just sent me this link confirming the unusual (or hitherto unkown) behavior of grey seals attacking and partially consuming Harbour porpoises off the coast of west Wales.
http://www.itv.com/news/wales/2015-04-09/world-first-grey-seal-caught-killing-and-eating-porpoise/
