The Shark Hunter

A crusty recluse on a Caribbean island who is dedicated to destroying sharks gets involved in a hunt for buried treasure.

Another Italian production starring the original DJANGO, Franco Nero. In this film Nero is a surly loner who spends most of his free time murdering sharks (sharks just couldn’t catch a break in the late 1970s-early 1980s) until he is forced into working for a crew of malcontents to retrieve a buried treasure in shark infested waters. This is another Enzo Castellari film and it includes some pretty cool underwater action scenes for the time plus tons of land-locked action as well. Really worth the time and energy to track down because it is a truly fun film.
https://www.youtube.com/watch?v=c_sFGnW1Wmg