Apparently these animals are normally fairly docile, I wonder in what way the animal was provoked, if any.
From BBC:
The flat, triangular stingray gets its name from the razor-sharp barb at the end of its tail, coated in toxic venom.
But the animal only uses this weapon defensively when it feels threatened or is stepped on.
Attacks on humans are a rarity - only two other people are known to have died in Australia from a stingray attack.
Experts say that while painful, stingray venom is rarely lethal and it would have been the wound caused by the barb itself which proved fatal.
http://news.bbc.co.uk/2/hi/asia-pacific/5313078.stm