The movie starring Morgan Freeman, Ashley Judd and Harry Connick Jr., which is based on a real story of a dolphin saved by a biologist and a young boy, netted $14.2 million, according to preliminary data from Exhibitor Relations.
"Moneyball," a sports drama starring Brad Pitt as a baseball coach, was in the number two spot, taking in $12.5 million.
"Lion King - 3D" was stripped of the top spot but still raked in $11.1 million in its third week. It has earned $79.7 million so far in re-release.
New films were in the fourth and fifth spots: "50/50", a comedy about a 27-year-old man's battle against cancer, which brought in $8.84 million. "Courageous," a police drama, brought in $8.8 million.
"Dream House," a thriller starring real-life couple Daniel Craig and Rachel Weisz, was in the sixth spot with $8.2 million.
"Abduction," a thriller with "Twilight" star Taylor Lautner, was in seventh place with $5.65 million in earnings.
"What's Your Number," the Anna Faris comedy about her search among her exes for the love of her life, came in eighth place with $5.6 million.
"Contagion," the Steven Soderbergh film starring Matt Damon and Gwyneth Paltrow, was in the number nine spot, earning $5.0 million. And "Killer Elite" was in 10th place earning $4.85 million.
Final figures are released on Monday.
Copyright AFP (Agence France-Presse), 2011