A dead humpback whale spotted drifting in Knik Arm last weekend has been marked as a navigational hazard according to federal officials, who haven’t learned much about how the whale died.

Julie Speegle, a spokeswoman for the National Oceanographic and Atmospheric Administration, said calls about the male humpback near Point MacKenzie started coming in Saturday evening. A military crew from Joint Base Elmendorf-Richardson responded to verify the location of the carcass, across the arm from the Port of Anchorage.

“They were able to get blubber samples and skin samples, and then they attached an orange buoy to it,” Speegle said.

A dead humpback whale floating in Knik Arm near Port MacKenzie has been marked with an orange buoy according to NOAA, which asks mariners to avoid the carcass. (NOAA Fisheries/MMPA/ESA Permit #18786)

The whale’s age and cause of death weren’t clear from that initial examination, Speegle said.

Mariners have been told to steer clear of the carcass, and NOAA isn’t expecting to conduct any further examinations of the carcass.

“We have no plans to do a necropsy, because it would just be too dangerous to secure it with the tides going out against the whale,” Speegle said. “Do not approach the whale -- it’s got that orange buoy on it, we know about it and people know to avoid it.”

NOAA has also received reports earlier in 2017 of two live gray whales swimming in Knik Arm, marking an above-average season of whale sightings in the area.

“Seems like more than usual this year,” Speegle said.

A dead humpback whale floating in Knik Arm near Port MacKenzie has been marked with an orange buoy according to NOAA, which asks mariners to avoid the carcass. (NOAA Fisheries/MMPA/ESA Permit #18786)