Conversation so far:
When did Steve Irwin die?
Steve Irwin died on  September 4 2006.
How did Steve Irwin die?
Irwin died after being pierced in the chest by a stingray barb.
Where was Steve Irwin when the sting ray struck?
He was filming in Australia's Great Barrier Reef.
was Steve Irwin shooting a documentary at the time of his death?
He was filming an underwater documentary titled Ocean's Deadliest.

Question: why did the sting ray strike him?
Self-contained rewrite: Why did the sting ray strike Steve Irwin?