A Ringling Bros. and Barnum & Bailey circus elephant and dog perform in New York on March 26, 2010

Across America through the decades, children of all ages delighted in the arrival of the circus, with its retinue of clowns, acrobats and, most especially, elephants.

But, bowing to from animal rights groups, the Ringling Bros. and Barnum & Bailey Circus announced Thursday it will phase out use of their emblematic Indian stars.

The company said the giant pachyderms will be gradually withdrawn from the big top, and will be gone from the show altogether by 2018.

Feld Entertainment—the parent company of America's best known circus—called the decision an "unprecedented change in the 145-year old 'Greatest Show On Earth'."

Thirteen of the animals currently part of the circus' migrating entourage will be relocated to the Ringling Bros. Center for Elephant Conservation in Florida, the company said.

It added that the retirement decision "was not easy, but it is in the best interest of our company, our elephants and our customers."

Family scions Nicola and Alana Feld, meanwhile, acknowledged that the decision to retire their elephant act is part of an ongoing cultural shift.

"As the circus evolves, we can maintain our focus on while allowing our business to continue to meet shifting consumer preferences," they said.

Clowns pose for a photo at Grand Central Terminal in New York City on February 24, 2015 as part of a media event

It once would have been unthinkable to have a big tent circus act without elephants, long a crowd favorite.

Animal rights activists over the years have become more organized, calling attention to what they have said called Ringling Bros. "cruelty" and influencing public opinion in the process.

Local officials also appeared to be paying closer attention to the company's violations of animal welfare rules.

Ringling Bros. in 2011 had to pay a $270,000 fine after receiving citations over how it treated its animals, among other infractions over the years.

An increasing number of US towns and cities also have adopted anti-elephant ordinances forbidding circus acts with elephants to enter the municipal limits.

Meanwhile, Ringling Bros. said it will continue to feature other animals in its acts, including tigers, lions, horses, dogs and camels.

Among Ringling Bros.' most vocal opponents over the years has been People for the Ethical Treatment of Animals, PETA, which waged an aggressive campaign against animal circus acts.

On its website Thursday, PETA declared "Victory!" against Ringling Bros., on its use of elephants, but the group seemed far from done in its decades-long battle against the Florida-based circus.

"The company's apparent change of heart comes too late for an eight-month-old baby elephant named Riccardo, who was destroyed after he fractured his hind legs when he fell from a circus pedestal; 4-year-old Benjamin, who drowned; and 3-year-old Kenny, who died after he was forced to perform despite being obviously ill," PETA said on its website.

As it makes its pivot away from using elephants, Ringling wants to highlight its conservation efforts, including a refuge in Florida created in 1995 to which the giant animals retire.

The company said it plans "to focus on its Asian elephant conservation programs, both here in North America and through its partnership with the island nation of Sri Lanka."

More than two dozen baby have been born at the enclave since it opened, helping to preserve the endangered animals, Feld Entertainment said.