Sharks and inflatables don't mix

I had never heard of inflatable catamarans before:

 Three people have been rescued in the Coral Sea off the coast of Cairns, after their catamaran was damaged during several shark attacks.

The Australian Maritime Safety Authority (Amsa) coordinated the rescue early Wednesday morning roughly 835km off the coast of Cairns, after receiving a distress beacon.

In a post to social media, the crew, who were on a round-the-world expedition called Russian Ocean Way, which they were documenting online, said they were first attacked by sharks on 4 September, leaving the rear left “cylinder” of their nine-metre inflatable catamaran damaged.

I wonder what the sharks were thinking, though.  I mean, I give orcas some credit for intelligence when attacking sail boats - but I wouldn't have thought sharks would keep attacking a boat.  Well, unless the crew had been particularly slack about throwing food scraps overboard, I guess.