``They behaved just like cattle,'' said New Minas fire chief Jim Redmond.
Four of the Atlantic white-sided dolphins showed up in the river in western Nova Scotia on Oct. 26. On Friday, two of them were spotted dead on the banks of the river, which winds from the Minas Basin and the Bay of Fundy.
The mammals apparently had trouble negotiating the river and were often seen stranded in the mud at low tide.
By Friday night, more dolphins had been spotted in the river at Port Williams.
On Saturday morning, firefighters were able to get seven in Port Williams and two in New Minas upright so they wouldn't drown. By Sunday, the number of dolphins had grown to 15.
Redmond called in a rescue team comprised of firefighters and they worked at corralling the dolphins and escorting them by boat the 12 kilometres or so to open water at high tide.
He said everything was going well until the dolphins balked at going under the bridge in Port Williams.
Firefighters had stopped traffic to keep the bridge quiet and prevent spooking of the mammals and were about to order pedestrians off the bridge when the dolphins finally went under it.
Once they hit the Minas Basin, Redmond said, the dolphins started an acrobatic show, jumping out of the water and wiggling their tails.
``It was almost like they were thanking us,'' he said.