WELLFLEET, Mass. — Animal rescuers were trying to keep dozens of dolphins away from shallow waters around Cape Cod on Saturday after 125 of the creatures stranded themselves a day earlier.

Teams in Massachusetts found one group of 10 Atlantic white-sided dolphins swimming in a dangerously shallow area at dawn on Saturday and managed to herd them out into deeper water, the International Fund for Animal Welfare said.

Scouts also found a second group of 25 dolphins swimming close to the shore near Eastham, the organization said, with herding efforts there ongoing as the tide dropped throughout the morning.

Ten dolphins died during the stranding Friday at The Gut — or Great Island — in Wellfleet, at the Herring River.

The organization said it was the largest mass-stranding it had dealt with on the Cape during its 26-year history in the area. The Gut is the site of frequent strandings, which experts believe is due in part to its hook-like shape and extreme tidal fluctuations.

Misty Niemeyer, the organization’s stranding coordinator, said rescuers faced many challenges Friday, including difficult mud conditions and the dolphins being spread out over a large area.

“It was a 12-hour exhausting response in the unrelenting sun, but the team was able to overcome the various challenges and give the dolphins their best chance at survival,” Niemeyer said in a statement.

The team started out on foot, herding the creatures into deeper waters, and then used three small boats equipped with underwater pingers, according to the organization.

Those helping with the rescue effort include more than 25 staff from the organization and 100 trained volunteers. The group also had the support of Whale and Dolphin Conservation, the Center for Coastal Studies, AmeriCorps of Cape Cod and the New England Aquarium.