An animal rights group says a rally at Marineland Saturday afternoon will be "one of the largest on-site demonstrations in the history of protest" at the popular attraction.

Marineland Animal Defense's (MAD) describes itself as "a campaign of concerned citizens determined to end animal captivity at Marineland."

It says its goals include ending breeding programs at the park and removing "captive animals to sanctuary sites."

The 51-year-old Niagara Falls park and its owner, John Holer, have come under fire this week after concerns were raised by former employees that poor water conditions had led to animals getting sick.

Jay Desroches, general manager of the Niagara Falls Humane Society, told QMI Agency on Thursday the agency will be inspecting the amusement park "in the very near future" to investigate allegations of animal mistreatment.

"We, in conjunction with the (Ontario Society for the Prevention of Cruelty to Animals) and other organizations plan on doing an inspection and an investigation at Marineland," DesRoches said. "I don't want to disclose when that will take place, but it will be in the very near future. It's a priority to us."

Along with traditional law enforcement services, the Ontario SPCA has the job of making sure the laws against animal abuse are followed. They enforce animal welfare legislation and investigate complaints using affiliates such as the Niagara Falls Humane Society.

On its site, Marineland says, "Our animals receive loving care from our trainers and our veterinary staff and enjoy well-maintained facilities, high quality diets and exemplary veterinary care. As a testament to the quality of our care, our animals live much longer than they would in the wild."

MAD says it will hold another protest outside the park next Sunday.