This is a developing story.

A local humpback whale calf named Tango was found dead Friday evening off the shore of Hump Island near Juneau, according to National Marine Fisheries Service Alaska region officials.

On Saturday biologists and veterinarians conducted a post-mortem exam of the calf following its discovery to determine the cause of death, according to Mandy Keogh, the Alaska region stranding coordinator.

“We were aware of it, and we responded and are investigating the cause of death of the calf as well as any of the surrounding anything that may have contributed to that,” she said. “He is a calf that a lot of people know. We definitely want the public to know that we’re aware of the concerns.”

Tango, a 2023-born calf of a well-known local humpback, Sasha, was discovered and reported by a local whale-watching vessel Friday evening, according to Keogh. On Saturday NOAA officials confirmed the body was located near the small island perpendicular to the National Shrine of St. Thérèse, beyond Shelter Island, and began an exam and investigation.

Keogh said a preliminary examination showed some injuries on Tango’s body and there was a report of a potential vessel strike in the area on Thursday. She said it’s unclear if Tango was involved in the strike, or if it caused or contributed to his death as the investigation is ongoing.

“One of the points of our examination is to determine whether or not it was something that would be associated with the cause of death or something that might have happened at a carcass afterward,” she said. “So we don’t know if that’s associated or if it’s a separate event at this time.”

She noted NOAA’s Office of Law Enforcement is investigating the potential interaction at this time.

According to Sam Dapcevich, spokesperson for Alaska Marine Highway System, on Thursday a passenger of the LeConte reported to NOAA that the ferry had struck a whale. Dapcevich said the vessel master reported that the ferry did indeed hit something, but said there were no signs of a whale strike.

“AMHS staff have been communicating with NOAA about the situation,” he said.

As of Monday afternoon, it remained undetermined if the LeConte’s reported strike was of Tango.

Marine mammals are protected under the Marine Mammal Protection Act, meaning people cannot collect parts or any tissues from a marine mammal, unless they are an Alaska Native and are using it for subsistence or handcraft, or have specific permits through NOAA.

Keogh encouraged people to steer clear of the area to respect the examination and to stay safe from any dangers from potential scavengers.

Keogh said people can contact the Alaska Marine Mammal Stranding Network 24-hour hotline number at (877) 925-7773 with any information regarding Tango’s death, or any other report about distressed, entangled or dead marine mammals.

• Contact reporter Clarise Larson at clarise.larson@juneauempire.com or (651) 528-1807.