The Department of Fisheries and Oceans says a necropsy performed on a killer whale found floating in a Vancouver Island inlet suggests no clear cause of death.

The department says the endangered male whale believed to be L95 was in an advanced state of decomposition when it was discovered on March 30 in Esperanza Inlet.

The southern resident killer whale was believed to be about 20 years old.

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Senior scientist Kenneth Balcomb of the Center for Whale Research in Friday Harbor, Wash., says the animal nicknamed Nigel was satellite tagged in February by the National Oceanic and Atmospheric Administration in the U.S.

He says a scar from the tag helped to identify the animal, but the tagging injury is considered coincidental.

The Fisheries Department also says a birthing defect could have caused the death of a two-week-old female killer whale calf found near Sooke, B.C., a week earlier.