What is the primary cause of boating fatalities?

Answer 1

Drinking.

Maybe in recreational boating, drinking would be a fair assessment. As far as professional maritime "fatalities" go, there are many contributing factors.

1) Loss of situational awareness.

2) Lack of training.

3) Complacency.

4.) Inexperience.

5.) Some sort of break down in communication (either electrical or verbal).

These are my observations, however if you read any amount of Maritime related casualties you will find these are all key components to accidents.