How do you get to the Grouper location were you have to kill 10 groupers (NVM Found)

[catloverplayer]

It seems like it's on land or I have a glitch. How do I get to this location? I need to complete this mission to open up another story mode.

 

[catloverplayer]

Nevermind I found them. I didn't know there was a crate you had to go thru.