Each year, more than 2,000,000 people visit the Seven Seas exhibit at the Brookfield Zoo in Chicago. The exhibit opened 50 years ago.
RITA STACEY: "This was a very groundbreaking facility."
Rita Stacey heads the Seven Seas exhibit at the Brookfield Zoo.
RITA STACEY: "It was actually the first inland dolphinarium. At the time, it was the first one that was located inland and it was the first one to use artificial saltwater, that we now create our own man-made saltwater here."
That development led to the creation of a permanent home for marine mammals far from the ocean. The Seven Seas exhibit is the oldest inland dolphin habitat in the United States.
RITA STACEY: "This is actually our second building. Our first building was being operated for close to 25 years. And in that 25 years, we had estimated about eleven and a half million people had gone into that facility and saw the dolphins there."
The Chicago Zoological Society operates the Brookfield Zoo. Stacey says the society has led efforts to increase understanding of sea creatures.
RITA STACEY: "There is so much that we've learned in the last 50 years about caring for dolphins, about the inner workings of their society and their relationships with each other, as well as about anatomy and about how dolphins actually work."
MELISSA ZABOJNIK: "You know, we can use the dolphins as ambassadors."
Melissa Zabojnik is a keeper at the Seven Seas exhibit.
MELISSA ZABOJNIK: "This is Mia. She's our youngest, she's four."
She has been working with dolphins for 10 years.
MELISSA ZABOJNIK: "The zoo's mission is to inspire conservation leadership, so that's something that we try to portray in our dolphin shows as well."
The Chicago Zoological Society provides support to the Sarasota Dolphin Research Center in Florida. The center studied dolphins in the Gulf of Mexico after the huge oil spill in 2010.
MELISSA ZABOJNIK: "Because we've gotten to know these animals so well in the past, it helps us in the future by determining if the oil spill has any effect on the future of them -- where the animals spend their time, if they migrate for any reason, if there's any difference of their health population in the future, year after year, because of the oil spill."
The Brookfield Zoo now works with other American organizations that are also far from ocean coastlines. They are working to increase understanding of the world under the sea. I'm Jim Tedder.