Sandy vomits from being seasick (heard, not seen), we later see some vomit on his shirt.
A man shoots a mother dolphin, and another young dolphin takes her to the surface for air, but she is shot a few more times and dies (there's no blood, but this entire sequence could easily disturb people).
A hammerhead attacks and kills a seagull, which we briefly see in its mouth. Afterwards blood is shown coming from the shark's mouth. The same shark later nearly attacks Sandy.
Sandy runs into the bathroom and we hear him vomit from smoking a cigar.
Sandy is nearly stabbed in the head with a fishing spear (but Flipper saves him).