What killed two whales off the Keys?

Two sperm whales died within seven days of each other in the Florida Keys, according to state and federal officials.

One was a juvenile whale that died May 4 off Key Largo. The other, a large adult that died after beaching itself near Mud Key, about 15 miles northeast of Key West in the Gulf of Mexico, was found on Tuesday, according to state wildlife officials.

The adult whale, a male, was towed to Robbie’s Marina on Stock Island, just east of Key West.

Kelly Richmond, spokeswoman for the Florida Fish and Wildlife Conservation Commission, said the whale is 47 feet long.

“We just started a necropsy on the animal now,” Richmond said Wednesday morning.

Casey Taylor, manager of Robbie’s Marina, said he was called at about 4 p.m. Tuesday about the whale.

He said it arrived at the marina via TowboatUS, a sea towing business, around 2:30 a.m. Wednesday. The marina workers used a travel lift to remove it from the water so it would not be damaged by fish. Taylor said the mammal weighs 40 tons.

The other whale was a newborn female calf that still had an open umbilical cord when it was found on a small barrier island off John Pennekamp Coral Reef State Park in Key Largo, said Blair Mase, southeast regional marine mammal stranding coordinator for the National Oceanic and Atmospheric Administration’s National Fisheries Service.

“It looks like it just separated from mom, and that was likely the cause of death,” Mase said, although the official cause of death is still pending necropsy results.

Given that the adult whale that died in the Gulf of Mexico was a male, there is likely no connection with the other death, Mase said.

Sperm whales are named for the waxy substance found in their heads that allows them to focus on sound. It is this substance that made them a target of when whaling was legal. The substance was used as lamp oil, lubricants and candles, according to NOAA.