After over four months of investigation into the death of a three-year-old Orca whale that drifted ashore onto Long Beach and discovered on February 11th, the investigators are no closer to the cause of her death.

The three-year-old calf, named L 112 or Sooke died as a result of massive trauma to her head, NOAA said in a report, “Gross examination disclosed extensive bruising and swelling on both sides of the head and neck, more pronounced on the right and continuing down the right side of the body,” the report notes.

“Although no skull fractures were seen during examination of the head, there was a fragmentation of the brain and increased fluid in the right side of the skull.”

While this type of injury is consistant with active sonar or an underwater explosion, a vessel strike, underwater earthquake or an encounter with another whale haven’t been ruled out.

According to NOAA, they contacted the Royal Canadian Navy and, “The Royal Canadian Navy confirmed the use of sonar and two small under water charges by HMCS Ottawa on Feb. 6, 2012, as part of an anti-submarine warfare exercise near Constance Bank and in the Straight of Juan de Fuca. HMCS Ottawa activities included following a Marine Mammal Mitigation Policy prior to and during the period when they were using ships’ sonar and prior to deploying the charges. Whales were not observed during that time.”

The U.S. Navy confirmed that their records showed that no sonar or explosives were used in the Northwest Training Range Complex during the period surrounding the calf’s death. This was confirmed by a follow-up call from the navy pointing out that their practice is a 30 day lookout, and there is nothing to point to any navy involvement in the matter.

During the time of the Orca’s death, fishing in the area is virtually non-existant during that time of year, and that no interactions with whales occured between fishing vessels and whales at that time.

Investigators surmise that the whale died near the Columbia River and drifted to Long Beach.

Sooke’s mother and brother have been spotted near Westport, Washington and exhibit no injuries.

More images of Sooke, or other whales of the Pacific Northwest can be seen at Jeanne Hyde’s A Whale of a “Purpose.”