MIAMI – The grieving dad of a hiker horrifically mauled to death by an alligator in a Florida river revealed how he received a harrowing call from her roommate as his daughter bled out.

Construction worker Brittany Clark’s arms were ripped apart by the massive gator Sunday during a trip with her boyfriend Chance Allison and roommate Jayden Hernandez as they swam in the Econlockhatchee River at Little Big Econ State Forest.

Allison desperately tried to wrench Clark from the 13-foot beast as it sunk its jaws into the 31-year-old, authorities said.

Clark was rushed to the hospital but is believed to have died from the enormous amounts of blood she lost.

Her shellshocked dad, 57-year-old Robert told The Post: “I received a call on Sunday from Brittany’s roommate Jayden and she was explaining as it was happening. They were trying to keep her alive and waiting for the authorities to show up.”

A semi-retired motorcycle technician who previously served in the US Navy, Robert said the family was already reeling from the death of his mother Barbara, 80, on Thursday when he learned his daughter was gruesomely killed.

Hernandez previously said the trio had joked about there being an alligator in the shallow, 3 feet of “murky” water that they were all standing in before disaster struck.

“There were air bubbles within our little triangle we made with our bodies in the water and I commented on how it might be a sneaky gator and Chance, Brittany’s boyfriend, swam right over it to show nothing was there and nothing was there,” Hernandez wrote in a lengthy Facebook post early Wednesday morning.