This is a older movie about a crocodile, or maybe a alligator. What I remember is a husband is trying to kill his wife and hopes the alligator will get her. It takes place in australia. She lives but goes after him. It may be a 70's movie?

It's the 1983 miniseries Return to Eden (http://www.imdb.com/title/tt0085079/).

That's it, thank you!