Cincinnati.com has an article on The Columbus Zoo and Aquarium about Manatees.

At its enclosed Manatee Coast and Discovery Reef exhibit, visitors learn about ocean reef ecosystems, the colorful fish that inhabit them, and the endangered manatee - thought to be the mythical creature of mermaid lore, as spun by old-world mariners.

The zoo's goal is to present the animals in exhibits that best mimic the natural environs in which they live, and warm-water enclosures house the manatees, unicorn tangs and other aquatic creatures on display.
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Since the exhibit opened in 1999, zoo visitors have contributed more than $40,000 to manatee conservation. These donations have supported research and conservation programs for manatees in the United States, Belize, Brazil and Colombia.