This is an awesome suggestion!
Would be really fun seeing something like this added to the game. Would fit perfectly with all the other creatures lurking in the ocean.
Hey, Exo here from play.exocraft.net.
Search for "Download lwjgl.dll" in any browser and download it from any of the websites listed. Then copy the file and paste it in the directory of the version of minecraft your trying to play.
The directory pathway should look something like this: "\AppData\Roaming\.minecraft\versions\1.8\1.8-natives-1582683832339\lwjgl.dll"
Hope this helps.