Box-office figures show how central Disney and DreamWorks are to the animation business. (Executives there declined to comment for this article.) Nielsen EDI, a box-office tracking service, said that 2004 was a banner year for animation, with domestic box-office receipts of $1.2 billion. That success was largely a result of the release of “Shrek 2” and “Shark Tale,” both from DreamWorks, as well as “The Incredibles” from Pixar.

In 2005, the domestic box office fell by half, to $640 million. Then Pixar did not release a feature film that year, and DreamWorks’ “Wallace and Gromit: The Curse of the Were-Rabbit” was a flop.

Through mid-September 2006, the domestic box office for animated films was $928 million. But there also has been a rise in the number of films — filmmakers plan to release 17 animated movies in 2006, compared with 11 in 2005.

If there is a shakeout and fewer animated movies are made, animators without a brand name or those who do not produce high-quality movies will probably be hurt most.

“There are a lot of movies out there,” said John H. Williams, a producer of “Shrek” and chief executive of Vanguard Animation. “The question is, ‘Who are the people who are going to be getting the funding?’ ”

The main criticism of animated movies within the industry and among consumers is that they are beginning to look alike. And the recent crop looks a lot like a zoo.

Natalie Ward, 13, who was out shopping with her grandmother, Bonnie Ward, in Hollywood recently, was unimpressed with the latest offerings. “There are so many movies with animals,” she said, pursing lips tinged blue by the icy neon drink in her hand. “The ones about cows are too, like, I don’t know — boring.”

Next month, Warner Brothers will distribute “Happy Feet,” featuring tap-dancing penguins. Rats are a favorite, too. Coming from DreamWorks is “Flushed Away,” the story of a high-class rat flushed down a toilet into London’s sewers, while “Ratatouille” from Pixar features a rat living in a fancy French restaurant.

These movies come on the heels of a menagerie of talking animal films, including “Over the Hedge” (raccoon, turtle, skunk), “Barnyard” (cows, mule, hen) and “The Wild” (lion, wildebeest, koala bear). Even “The Ant Bully” looked like a reworking of previous insect-themed movies like “A Bug’s Life” and “Antz,” both released in 1998.

“I think we need to branch out and find a wider breadth of stories to tell,” said Gary Ross, the director of “Pleasantville” and “Seabiscuit,” who is producing the animated film “The Tale of Despereaux,” based on a best-selling book that features a rat, a servant girl and a mouse who cross paths. “We just have to find a diversity of narratives.”

Still, it is no wonder that Hollywood is flush with fuzzy creatures. A few years ago “animated films were the most profitable,” said Mr. Williams. That was particularly true because they were nearly guaranteed to be best sellers on DVD. But making animated movies is expensive — some cost upward of $150 million — and that makes it especially risky to bore consumers.