Trivia: Brody's line, "You're gonna need a bigger boat", was actually a total ad-lib. The director wanted a real reaction to the shark popping up really close to him, so they didn't tell Roy Scheider that it was going to happen. It was a total surprise. Not only did he react naturally, it scared him so badly that he forgot the correct line. So, when he looked at Quint, he ad-libbed, and they left it in the movie. (It was number 35 on the top 100 Most Memorable Movie Quotes list).
Robert Cotton
15th Apr 2014