Here is the full list of all 18 Wakeboarding HD trophies - there are 15 bronze and 3 silver.
Ride 25 km without falling (in completed missions).
Fall 500 times in completed missions.
Become lunch for a hundred sharks (in completed missions).
Let a shark eat you when your score multiplier is 20 or higher.
Perform each trick (except Balance and Slide) 10 times in completed missions.
Spend 1 hour in the air in completed missions.
Maintain the “S” rating for overall 10 minutes throughout the game (in completed missions).
Earn 12 souvenirs.
Spend 5 minutes balancing in completed missions.
Increase score multiplier to 20 or more for both players in Split Screen simultaneously (you don’t have to score points).
Win all game missions (in original game).
Earn gold medals in any 10 missions.
Score twice as much points as required in any mission where the points are one of the goals.
Break, overturn, and crash or sweep away 500 objects in completed missions.
Collect 100 stars in a single Action Chain.
Win 10 times (gold medal + all additional goals) in a row in any different single player missions.
Earn all souvenirs (in original game).
Score points with multiplier that equals to 50 or higher.